Internet DRAFT - draft-ietf-manet-dlep
draft-ietf-manet-dlep
Mobile Ad hoc Networks Working S. Ratliff
Group B. Berry
Internet-Draft G. Harrison
Intended status: Standards Track D. Satterwhite
Expires: August 10, 2012 Cisco Systems
S. Jury
NetApp
February 6, 2012
Dynamic Link Exchange Protocol (DLEP)
draft-ietf-manet-dlep-02
Abstract
When routing devices rely on modems to effect communications over
wireless links, they need timely and accurate knowledge of the
characteristics of the link (speed, state, etc.) in order to make
forwarding decisions. In mobile or other environments where these
characteristics change frequently, manual configurations or the
inference of state through routing or transport protocols does not
allow the router to make the best decisions. A bidirectional, event-
driven communication channel between the router and the modem is
necessary.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
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This Internet-Draft will expire on August 10, 2012 .
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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(http://trustee.ietf.org/license-info) in effect on the date of
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . 6
2. Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Metrics . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5. Extensions to DLEP . . . . . . . . . . . . . . . . . . . . . . 8
6. Normal Session Flow . . . . . . . . . . . . . . . . . . . . . 8
7. Generic DLEP Packet Definition . . . . . . . . . . . . . . . . 9
8. Message Header Format . . . . . . . . . . . . . . . . . . . . 10
9. Message TLV Block Format . . . . . . . . . . . . . . . . . . . 10
10. DLEP Sub-TLVs . . . . . . . . . . . . . . . . . . . . . . . . 11
10.1. Identification Sub-TLV. . . . . . . . . . . . . . . . . . 12
10.2. DLEP Version Sub-TLV. . . . . . . . . . . . . . . . . . . 13
10.3. Peer Type Sub-TLV . . . . . . . . . . . . . . . . . . . . 14
10.4. MAC Address Sub-TLV . . . . . . . . . . . . . . . . . . . 14
10.5. IPv4 Address Sub-TLV. . . . . . . . . . . . . . . . . . . 15
10.6. IPv6 Address Sub-TLV. . . . . . . . . . . . . . . . . . . 16
10.7. Maximum Data Rate Sub-TLV . . . . . . . . . . . . . . . . 16
10.8. Current Data Rate Sub-TLV . . . . . . . . . . . . . . . . 17
10.9. Latency Sub-TLV . . . . . . . . . . . . . . . . . . . . . 18
10.10. Resources Sub-TLV . . . . . . . . . . . . . . . . . . . . 18
10.11. Expected Forwarding Time Sub-TLV. . . . . . . . . . . . . 19
10.12. Relative Link Quality Sub-TLV . . . . . . . . . . . . . . 20
10.13. Peer Termination Sub-TLV. . . . . . . . . . . . . . . . . 20
10.14. Heartbeat Interval Sub-TLV. . . . . . . . . . . . . . . . 21
10.15. Heartbeat Threshold Sub-TLV . . . . . . . . . . . . . . . 21
10.16. Link Characteristics ACK Timer Sub-TLV. . . . . . . . . . 22
10.17. Credit Window Status Sub-TLV. . . . . . . . . . . . . . . 23
10.18. Credit Grant Sub-TLV. . . . . . . . . . . . . . . . . . . 24
10.19. Credit Request Sub-TLV. . . . . . . . . . . . . . . . . . 24
11. DLEP Protocol Messages . . . . . . . . . . . . . . . . . . . 25
11.1. Message Block TLV Values . . . . . . . . . . . . . . . . 25
12. Peer Discovery Messages . . . . . . . . . . . . . . . . . . . 26
12.1. Attached Peer Discovery Message . . . . . . . . . . . . . 26
12.2. Detached Peer Discovery Message . . . . . . . . . . . . . 27
13. Peer Offer Message . . . . . . . . . . . . . . . . . . . . . . 29
14. Peer Update Message. . . . . . . . . . . . . . . . . . . . . . 30
15. Peer Update ACK Message. . . . . . . . . . . . . . . . . . . . 31
16. Peer Termination Message . . . . . . . . . . . . . . . . . . . 32
17. Peer Termination ACK Message . . . . . . . . . . . . . . . . . 33
18. Neighbor Up Message . . . . . . . . . . . . . . . . . . . . . 33
19. Neighbor Up ACK Message. . . . . . . . . . . . . . . . . . . . 35
20. Neighbor Down Message . . . . . . . . . . . . . . . . . . . . 35
21. Neighbor Down ACK Message. . . . . . . . . . . . . . . . . . . 36
22. Neighbor Update Message . . . . . . . . . . . . . . . . . . . 37
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23. Neighbor Address Update Message. . . . . . . . . . . . . . . . 38
24. Neighbor Address Update ACK Message. . . . . . . . . . . . . . 39
25. Heartbeat Message . . . . . . . . . . . . . . . . . . . . . . 40
26. Link Characteristics Message . . . . . . . . . . . . . . . . . 40
27. Link Characteristics ACK Message . . . . . . . . . . . . . . . 42
28. Security Considerations. . . . . . . . . . . . . . . . . . . . 43
29. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 43
29.1 TLV Registrations. . . . . . . . . . . . . . . . . . . . . 43
29.2 Expert Review: Evaluation Guidelines . . . . . . . . . . . 43
29.3 Message TLV Type Registrations . . . . . . . . . . . . . . 43
29.4 DLEP Order Registrations . . . . . . . . . . . . . . . . . 44
29.5 DLEP Sub-TLV Type Registrations. . . . . . . . . . . . . . 44
30. Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . 45
1. Introduction
There exist today a collection of modem devices that control links of
variable bandwidth and quality. Examples of these types of links
include line-of-sight (LOS) radios, satellite terminals, and cable/
DSL modems. Fluctuations in speed and quality of these links can
occur due to configuration (in the case of cable/DSL modems), or on a
moment-to-moment basis, due to physical phenomena like multipath
interference, obstructions, rain fade, etc. It is also quite possible
that link quality and bandwidth varies with respect to individual
neighbors on a link, and with the type of traffic being sent. As an
example, consider the case of an 802.11g access point, serving 2
associated laptop computers. In this environment, the answer to the
question "What is the bandwidth on the 802.11g link?" is "It depends
on which associated laptop we're talking about, and on what kind of
traffic is being sent." While the first laptop, being physically
close to the access point, may have a bandwidth of 54Mbps for
unicast traffic, the other laptop, being relatively far away, or
obstructed by some object, can simultaneously have a bandwidth of
only 32Mbps for unicast. However, for multicast traffic sent from the
access point, all traffic is sent at the base transmission rate
(which is configurable, but depending on the model of the access
point, is usually 24Mbps or less).
In addition to utilizing variable bandwidth links, mobile networks
are challenged by the notion that link connectivity will come and go
over time. Effectively utilizing a relatively short-lived connection
is problematic in IP routed networks, as routing protocols tend to
rely on independent timers at OSI Layer 3 to maintain network
convergence (e.g. HELLO messages and/or recognition of DEAD routing
adjacencies). These short-lived connections can be better utilized
with an event-driven paradigm, where acquisition of a new neighbor
(or loss of an existing one) is somehow signaled, as opposed to a
timer-driven paradigm.
Another complicating factor for mobile networks are the different
methods of physically connecting the modem devices to the router.
Modems can be deployed as an interface card in a router's
chassis, or as a standalone device connected to the router via
Ethernet, USB, or even a serial link. In the case of Ethernet or
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serial attachment, with existing protocols and techniques, routing
software cannot be aware of convergence events occurring on the
radio link (e.g. acquisition or loss of a potential routing
neighbor), nor can the router be aware of the actual capacity of
the link. This lack of awareness, along with the variability in
bandwidth, leads to a situation where quality of service (QoS)
profiles are extremely difficult to establish and properly
maintain. This is especially true of demand-based access schemes
such as Demand Assigned Multiple Access (DAMA) implementations
used on some satellite systems. With a DAMA-based system,
additional bandwidth may be available, but will not be used
unless the network devices emit traffic at rate higher than the
currently established rate. Increasing the traffic rate does not
guarantee additional bandwidth will be allocated; rather, it may
result in data loss and additional retransmissions on the link.
In attempting to address the challenges listed above, the authors
have developed the Data Link Exchange Protocol, or DLEP. The DLEP
protocol runs between a router and its attached modem devices,
allowing the modem to communicate link characteristics as they
change, and convergence events (acquisition and loss of potential
routing neighbors). The following diagrams are used to illustrate
the scope of DLEP sessions.
|-----Local Neighbor-----| |-----Remote Neighbor----|
| | | (far-end device) |
+--------+ +-------+ +-------+ +--------+
| Router |=======| Modem |{~~~~~~~~}| Modem |=======| Router |
| | | Device| | Device| | |
+--------+ +-------+ +-------+ +--------+
| | | Link | | |
|-DLEP--| | Protocol | |-DLEP--|
| | | (e.g. | | |
| | | 802.11) | | |
Figure 1: DLEP Network
In Figure 1, when a local client (Modem device) detects the
presence of a remote neighbor, it sends an indication to its
local router via the DLEP session. Upon receipt of the indication,
the local router would take appropriate action (e.g. initiation
of discovery or HELLO protocols) to converge the network. After
notification of the new neighbor, the modem device utilizes the
DLEP session to report the characteristics of the link (bandwidth,
latency, etc) to the router on an as-needed basis.
DLEP is independent of the underlying link type and topology.
Figure 2 shows how DLEP can support a configuration whereby
routers are connected with different link types and with different
network configurations. In this setup, the routers are connected
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with two different devices (Modem device A and Modem device B).
Modem A is connected via a point-to-point link, whereas Modem B
is connected via a shared medium. In both cases, the DLEP session
is used to report the characteristics of the link (bandwidth,
latency, etc.) to network neighbors on an as-needed basis. The
modem is also able to use the DLEP session to notify the router
when the remote neighbor is lost, shortening the time required to
re-converge the network.
+--------+ +--------+
+------+ Modem A| | Modem A+-----+
| | Device | <===== // ======> | Device | |
| +--------+ P-t-P Link +--------+ |
| Protocol |
+---+----+ +---+----+
| Router | | Router |
| | | |
+---+----+ +---+----+
| +
| +--------+ +--------+ |
+------+ Modem B| | Modem B| |
| Device | o o o o o o o o | Device +-----+
+--------+ o Shared o +--------+
o Medium o
o o
o o
o o
o
+--------+
| Modem B|
| Device |
+---+----+
|
|
+---+----+
| Router |
| |
+--------+
Figure 2: DLEP Network with Multiple Modem Devices
DLEP exists as a collection of type-length-value (TLV) based messages
using [RFC5444] formatting. The protocol can be used for both Ethernet
attached modems (utilizing, for example, a UDP socket for transport
of the RFC 5444 packets), or in environments where the modem is an
interface card in a chassis (via a message passing scheme). DLEP
utilizes a session paradigm between the modem device and its
associated router. If multiple modem devices are attached to a
router (as in FIgure 2), a separate DLEP session MUST exist for each
modem. If a modem device supports multiple connections to a router
(via multiple logical or physical interfaces), or supports
connections to multiple routers, a separate DLEP session MUST exist
for each connection.
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1.1 Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14, RFC 2119
[RFC2119].
2. Assumptions
In order to implement discovery in the DLEP protocol (thereby
avoiding some configuration), we have defined a first-speaker and a
passive-listener scheme. Borrowing from existing terminology, this
document refers to the first-speaker as the 'client', and the passive
listener as the 'server', even though there is no client/server
relationship in the classic sense. In a typical deployment, a router
would appear as the DLEP 'server', and an attached modem device would
act as the 'client' (e.g. the initiator for discovery).
DLEP assumes that participating clients appear to the server as a
transparent bridge - specifically, the assumption is that the
destination MAC address for data traffic in any frame emitted by
the server should be the MAC address of the next-hop router or end-
device, and not the MAC address of any of the intervening clients.
DLEP assumes that security on the session (e.g. authentication of
session partners, encryption of traffic, or both) is dealt with by
the underlying transport mechanism for the RFC 5444 packets (e.g. by
using a transport such as DTLS [DTLS]).
DLEP utilizes a session-oriented paradigm. There are two classes
of sessions - the first is identified as a 'peer session'. The
peer session exists between a DLEP server and a DLEP client. All
DLEP messages between client and server are transmitted within the
context of the peer session.
The other type of DLEP session is referred to as a 'neighbor session'.
Neighbor sessions can be instantiated by either the DLEP server or
client, and represent an identifiable destination (i.e. an address)
within the network. Examples of a destination would be a unicast
address (for either a next-hop router, or for an end-station), or
a multicast address. A DLEP neighbor session MUST exist for every
destination that exists in the network.
The optional [RFC5444] message header Sequence Number MUST be
included in all DLEP packets. Sequence Numbers start at 1 and are
incremented by one for each original and retransmitted message. The
unsigned 16-bit Sequence Number rolls over at 65535 to 1. A
Sequence Number of 0 is not valid. Sequence Numbers are unique
within the context of a DLEP session. Sequence numbers are used in
DLEP to correlate a response to a request.
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3. Credits
DLEP includes an OPTIONAL credit-windowing scheme analogous to the
one documented in [RFC5578]. In this scheme, traffic between the
DLEP client and the DLEP server is treated as two unidirectional
windows. This document identifies these windows as the "Client
Receive Window", or CRW, and the "Server Receive Window", or SRW.
If credits are used, they MUST be granted by the receiver on a
given window - that is, on the "Client Receive Window" (CRW),
the DLEP client is responsible for granting credits to the server,
allowing it (the server) to send data to the client. Likewise,
the DLEP server is responsible for granting credits on the SRW,
which allows the client to send data to the server.
DLEP expresses all credit data in number of octets. The total number
of credits on a window, and the increment to add to a grant, are
always expressed as a 64-bit unsigned quantity.
If used, credits are managed on a neighbor session basis; that is,
separate credit counts are maintained for each neighbor session
requiring the service. Credits do not apply to DLEP peer sessions.
4. Metrics
DLEP includes the ability for the client and server to communicate
metrics that reflect the characteristics (e.g. bandwidth, latency)
of the variable-quality link in use. As mentioned in the
introduction section of this document, metrics have to be used
within a context - for example, metrics to a unicast address in
the network. DLEP allows for metrics to be sent within two
contexts - neighbor session context (those for a given destination
within the network), and peer session context (those that apply
to all destinations accessed via the DLEP client). Metrics
supplied on DLEP Peer messages are, by definition, in the context
of a peer session; metrics supplied on Neighbor messages are, by
definition, used in the context of a neighbor session.
Supplying metrics in a peer session context gives clients the
ability to supply default metrics on a 'device-wide' basis. It is
left to implementations to choose sensible default values based on
their specific characteristics. Additionally, the metrics (either
at a peer or neighbor session context) MAY be used to report non-
changing, or static, metrics. Clients having static link metric
characteristics SHOULD report metrics only once for a given
neighbor session (or peer session, if all connections via the client
are of this static nature).
The approach of allowing for different contexts for metric data
increases both the flexibility and the complexity of using metric
data. This document details the mechanism whereby the data is
transmitted, however, the specific algorithms for utilizing the
dual-context metrics is out of scope and not addressed by this
document.
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5. Extensions to DLEP
While this draft represents the best efforts of the co-authors, and
the working group, to be functionally complete, it is recognized
that extensions to DLEP will in all likelihood be necessary as more
link types are utilized. To allow for future innovation, the draft
allocates numbering space for experimental orders and sub-TLVs. DLEP
implementations MUST be capable of parsing and acting on the orders
and sub-TLVs as documented in this specification. DLEP orders/sub-TLVs
in the experimental numbering range SHOULD be silently dropped by an
implementation if they are not understood. The intent of the
experimental numbering space is to allow for further development of
DLEP protocol features and function. If subsequent development yields
new features with sufficient applicability, those features should be
either included in an update of this specification, or documented in
a standalone specification.
6. Normal Session Flow
A session between a client and a server is established by exchanging
the "Peer Discovery" and "Peer Offer" messages described below.
The flows described in this document create a state-full protocol
between client and server. Both client and server initialize in a
"discovery" state, and the client issues a "Peer Discovery" message.
When the server receives a Peer Discovery, it responds with a "Peer
Offer" message, and enters an "in session" state with the client.
Receipt of the Peer Offer at the client causes it (the client) to
transition into the "in session" state.
Once that exchange has successfully occurred, messages transferred
in the context of the peer session will consist of
o Periodic 'Heartbeat' messages, intended to keep the peer session
alive, and to verify bidirectional connectivity, and/or
o Peer Update messages, indicating some change in status that one
of the peers needs to communicate to the other.
In addition to the messages above, the peers will transmit DLEP
messages concerning destinations in the network. These messages
trigger creation/maintenance/termination of 'neighbor sessions'. For
example, a peer will inform its DLEP partner of the presence of a
new destination via the "Neighbor Up" message. Receipt of a Neighbor
Up causes the receiving peer to allocate the necessary resources,
creating a neighbor session, and transition to an "in session" state
on the newly created neighbor session. The in-session state persists
until notification of neighbor loss is received, or by optional
timeout due to inactivity.
The loss of a destination is communicated via the "Neighbor Down"
message, and changes in status to the destination (e.g. varying
link quality, or addressing changes) are communicated via a
"Neighbor Update" message.
Again, metrics can be expressed within the context of a neighbor
session via the Neighbor Update message, or within the context of
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a peer session (reflecting the link as a whole) via the Peer Update
message. In cases where metrics are provided on the peer session, the
receiving peer MUST propagate the metrics to all neighbor sessions
accessed via the peer. A DLEP peer MAY send metrics both in a peer
session context (via the Peer Update message) and a neighbor session
context (via Neighbor Update) at any time. The heuristics for
applying received peer session and neighbor session metrics is left
to implementations.
In addition to receiving metrics about the link, DLEP provides for
the ability for a server to request a different amount of bandwidth,
or latency, from the client via the Link Characteristics Message.
This allows the server to deal with requisite increases (or decreases)
of allocated bandwidth/latency in demand-based schemes in a more
deterministic manner.
7. Generic DLEP Packet Definition
The Generic DLEP Packet Definition follows the format for packets
defined in [RFC5444].
The Generic DLEP Packet Definition contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| Flags | Packet Sequence Number | Packet TLV |
| | | | Block... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message (Contains DLEP message)... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Version - Version of RFC 5444 specification on
which the packet/messages/TLVs are
constructed.
Flags - 4 bit field. All bits MUST be ignored
by DLEP implementations.
Packet Sequence Number - If present, the packet sequence number
is parsed and ignored. DLEP does NOT
use or generate packet sequence numbers.
Packet TLV block - A TLV block which contains packet level
TLV information. DLEP implementations
MUST NOT use this TLV block.
Message - The packet MAY contain zero or more
messages, however, DLEP messages are
encoded within an RFC 5444 Message
TLV Block.
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8. Message Header Format
DLEP utilizes the following format for the RFC 5444 message header
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type |Msg Flg|AddrLen| Message Size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num | TLV Block... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - An 8-bit field which specifies the type
of the message. For DLEP, this field
contains DLEP_MESSAGE (value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit is
set). All other bits are unused and MUST
be set to '0'.
Message Address Length - A 4-bit unsigned integer field encoding the
length of all addresses included in this
message. DLEP implementations do not use
this field; contents SHOULD be ignored.
Message Size - A 16-bit unsigned integer field which
specifies the number of octets that make up
the message including the message header.
Message Sequence Number - A 16-bit unsigned integer field that
contains a sequence number, generated by
the originator of the message. Sequence
numbers range from 1 to 65535. Sequence
numbers roll over at 65535 to 1; 0 is
invalid.
TLV Block - TLV Block included in the message.
9. Message TLV Block Format
The DLEP protocol is organized as a set of orders, each with a
collection of Sub-TLVs. The Sub-TLVs carry information needed
to process and/or establish context (e.g. the MAC address of a
far-end router), and the 'tlv-type' field in the message TLV
block carries the DLEP order itself. The DLEP orders are
enumerated in section 11.1 of this document, and the messages
created using these orders are documented in sections 12 through
27.
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DLEP uses the following settings for an RFC 5444 Message TLV
block:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TLVs Length | TLV Type | TLV Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Value... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLVs Length - A 16-bit unsigned integer field that contains the total
number of octets in all of the immediately following
TLV elements (tlvs-length not included).
TLV Type - An 8-bit unsigned integer field specifying the type
of the TLV. DLEP uses this field to specify the DLEP
order. Valid DLEP orders are defined in section 11.1
of this document.
TLV Flags - An 8-bit flags bit field. Bit 3 (thasvalue) MUST be
set; all other bits are not used and MUST be set
to '0'.
Length - Length of the 'Value' field of the TLV
Value - A field of length <Length> which contains data
specific to a particular TLV type. In the DLEP
case, this field will consist of a collection of
DLEP sub-TLVs appropriate for the DLEP action
specified in the TLV type field.
10. DLEP sub-TLVs
DLEP protocol messages are transported in an RFC 5444 message TLV.
All DLEP messages use the RFC 5444 DLEP_MESSAGE value (TBD). The
protocol messages consist of a DLEP order, encoded in the 'tlv-type'
field in the message TLV block, with the 'value' field of the TLV
block containing a collection (1 or more) DLEP sub-TLVs.
The format of DLEP Sub-TLVs is consistent with RFC 5444 in that the
Sub-TLVs contain a flag field in addition to the type, length, and
value fields. Valid DLEP Sub-TLVs are:
TLV TLV
Value Description
=========================================
TBD Identification sub-TLV
TBD DLEP Version sub-TLV
TBD Peer Type sub-TLV
TBD MAC Address sub-TLV
TBD IPv4 Address sub-TLV
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TBD IPv6 Address sub-TLV
TBD Maximum Data Rate (MDR) sub-TLV
TBD Current Data Rate (CDR) sub-TLV
TBD Latency sub-TLV
TBD Resources sub-TLV
TBD Expected Forwarding Time (ETX) sub-TLV
TBD Relative Link Quality (RLQ) sub-TLV
TBD Status sub-TLV
TBD Heartbeat Interval sub-TLV
TBD Heartbeat Threshold sub-TLV
TBD Neighbor down ACK timer sub-TLV
TBD Link Characteristics ACK timer sub-TLV
TBD Credit Window Status sub-TLV
TBD Credit Grant sub-TLV
TBD Credit Request sub-TLV
DLEP sub-TLVs contain the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TLV Type |TLV Flags=0x10 | Length | Value... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - An 8-bit unsigned integer field specifying the type
of the sub-TLV.
TLV Flags - An 8-bit flags bit field. Bit 3 (thasvalue) MUST be
set, all other bits are not used and MUST be set to
'0'.
Length - An 8-bit length of the value field of the sub-TLV
Value - A field of length <Length> which contains data
specific to a particular sub-TLV.
10.1 Identification Sub-TLV
This Sub-TLV MUST exist in the TLV Block for all DLEP messages, and
MUST be the first Sub-TLV of the message. Further, there MUST be ONLY
one Identification Sub-TLV in an RFC 5444 message TLV block. The
Identification sub-TLV contains client and server identification
information used to establish the proper context for processing DLEP
protocol messages.
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The Identification sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type = TBD |TLV Flags=0x10 |Length = 8 | Server ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Server ID | Client ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Client ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - Value TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are
unused and MUST be set to '0'.
Length - 8
Server ID - Indicates the Server ID of the DLEP session.
Client ID - indicates the Client ID of the DLEP session.
When the client initiates discovery (via the Peer Discovery message),
it MUST set the Client ID to a 32-bit quantity that will be used to
uniquely identify this session from the client-side. The client MUST
set the Server ID to '0'. When responding to the Peer Discovery
message, the server MUST echo the Client ID, and MUST supply its own
unique 32-bit quantity to identify the session from the server's
perspective. After the Peer Discovery/Peer Offer exchange, both the
Client ID and the Server ID MUST be set to the values obtained from
the Peer DIscovery/Peer Offer sequence.
10.2 DLEP Version Sub-TLV
The DLEP Version Sub-TLV is an OPTIONAL TLV in both the Peer
Discovery and Peer Offer messages. The Version Sub-TLV is used to
indicate the client or server version of the protocol. The client
and server MAY use this information to decide if the peer is running
at a supported level.
The DLEP Version Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length=4 | Major Version |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Major Version | Minor Version |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
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TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are
not used and MUST be set to '0'.
Length - Length is 4
Major Version - Major version of the client or router protocol.
Minor Version - Minor version of the client or router protocol.
Support of this draft is indicated by setting the Major Version
to '1', and the Minor Version to '2' (e.g. Version 1.2).
10.3 Peer Type Sub-TLV
The Peer Type Sub-TLV is used by the server and client to give
additional information as to its type. It is an OPTIONAL sub-TLV in
both the Peer Discovery Message and the Peer Offer message. The peer
type is a string and is envisioned to be used for informational
purposes (e.g. as output in a display command).
The Peer Type sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length= peer |Peer Type Str |
| | |type string len|Max Len = 80 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits
are not used and MUST be set to '0'.
Length - Length of peer type string (80 bytes maximum).
Peer Type String - Non-Null terminated peer type string, maximum
length of 80 bytes. For example, a satellite
modem might set this variable to 'Satellite
terminal'.
10.4 MAC Address Sub-TLV
The MAC address Sub-TLV MUST appear in all neighbor-oriented
messages (e.g. Neighbor Up, Neighbor Up ACK, Neighbor Down, Neighbor
Down ACK, Neighbor Update, Link Characteristics Request, and Link
Characteristics ACK). The MAC Address sub-TLV contains the address
of the far-end (neighbor) destination, and may be either a physical
or a virtual destination. Examples of a virtual destination would
be a multicast MAC address, or the broadcast MAC (0xFFFFFFFFFFFF).
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The MAC Address sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 6 |MAC Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MAC Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MAC Address |
+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are not
used and MUST be set to '0'.
Length - 6
MAC Address - MAC Address of the destination (either physical or
virtual).
10.5 IPv4 Address Sub-TLV
The IPv4 Address Sub-TLV MAY be used in Neighbor Up, Neighbor
Update, and Peer Update Messages, if the client is aware of the
Layer 3 address. When included in Neighbor messages, the IPv4
Address sub-TLV contains the IPv4 address of the far-end neighbor.
In the Peer Update message, it contains the IPv4 address of the
sending peer. In either case, the sub-TLV also contains an
indication of whether this is a new or existing address, or is a
deletion of a previously known address.
The IPv4 Address Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 5 | Add/Drop |
| | | | Indicator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are not
used and MUST be set to '0'.
Length - 5
Add/Drop - Value indicating whether this is a new or existing
Indicator address (0x01), or a withdrawal of an address (0x02).
IPv4 Address - IPv4 Address of the far-end neighbor or peer.
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10.6 IPv6 Address Sub-TLV
The IPv6 Address Sub-TLV MAY be used in Neighbor Up, Neighbor
Update, and Peer Update Messages, if the client is aware of the
Layer 3 address. When included in Neighbor messages, the IPv6
Address sub-TLV contains the IPv6 address of the far-end neighbor.
In the Peer Update, it contains the IPv6 address of the
originating peer. In either case, the sub-TLV also contains an
indication of whether this is a new or existing address, or is a
deletion of a previously known address.
The IPv6 Address sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 17 | Add/Drop |
| | | | Indicator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are not
used and MUST be set to '0'.
Length - 17
Add/Drop - Value indicating whether this is a new or
Indicator existing address (0x01), or a withdrawal of
an address (0x02).
IPv6 Address - IPv6 Address of the far-end neighbor or peer.
10.7 Maximum Data Rate Sub-TLV
The Maximum Data Rate (MDR) Sub-TLV is used in Neighbor Up, Neighbor
Update, Peer Discovery, Peer Update, and Link Characteristics ACK
Messages to indicate the maximum theoretical data rate, in bits per
second, that can be achieved on the link. When metrics are reported
via the messages listed above, the maximum data rate MUST be reported.
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The Maximum Data Rate sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 8 | MDR (bps) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MDR (bps) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MDR (bps) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other
bits are not used and MUST be set to '0'.
Length - 8
Maximum Data Rate - A 64-bit unsigned number, representing the
maximum theoretical data rate, in bits per
second (bps), that can be achieved on the
link.
10.8 Current Data Rate Sub-TLV
The Current Data Rate (CDR) Sub-TLV is used in Neighbor Up, Neighbor
Update, Peer Discovery, Peer Update, Link Characteristics Request,
and Link Characteristics ACK messages to indicate the rate at which
the link is currently operating, or in the case of the Link
Characteristics Request, the desired data rate for the link.
The Current Data Rate sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 8 |CDR (bps) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CDR (bps) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CDR (bps) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other
bits are not used and MUST be set to '0'.
Length - 8
Current Data Rate - A 64-bit unsigned number, representing the
current rate, in bits per second (bps),
on the link. When reporting metrics (e.g,
in Neighbor Up, Neighbor Down, Peer
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Discovery, Peer Update, or Link
Characteristics ACK), if there is no
distinction between current and maximum
data rates, current data rate SHOULD be
set equal to the maximum data rate.
10.9 Expected Forwarding Time Sub-TLV
The Expected Forwarding Time (EFT) Sub-TLV is used in Neighbor Up,
Neighbor Update, Peer Discovery, and Peer Update messages to indicate
the typical latency between the arrival of a given packet at the
transmitting device and the reception of the packet at the other end
of the link. EFT combines transmission time, idle time, waiting time,
freezing time, and queuing time to the degree that those values are
meaningful to a given transmission medium.
The Expected Forwarding Time sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 4 | EFT (ms) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| EFT |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other
bits are not used and MUST be set to '0'.
Length - 4
Current Data Rate - A 32-bit unsigned number, representing the
expected forwarding time, in milliseconds,
on the link.
10.10 Latency Sub-TLV
The Latency Sub-TLV is used in Neighbor Up, Neighbor Update, Peer
Discovery, Peer Update, Link Characteristics Request, and Link
Characteristics ACK messages to indicate the amount of latency on
the link, or in the case of the Link Characteristics Request, to
indicate the maximum latency required (e.g. a should-not-exeed value)
on the link.
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The Latency Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 2 |Latency (ms) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Latency (ms) |
+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other
bits are not used and MUST be set to '0'.
Length - 2
Latency - The transmission delay that a packet
encounters as it is transmitted over the
link. In Neighbor Up, Neighbor Update,
and Link Characteristics ACK, this value
is reported in absolute delay, in
milliseconds. The calculation of latency
is implementation dependent. For example,
the latency may be a running average
calculated from the internal queuing. If
a device cannot calculate latency, it
SHOULD be reported as 0. In the Link
Characteristics Request Message, this value
represents the maximum delay, in
milliseconds, expected on the link.
10.11 Resources Sub-TLV
The Resources Sub-TLV is used in Neighbor Up, Neighbor Update, Peer
Discovery, Peer Update, and Link Characteristics ACK messages to
indicate a percentage (0-100) amount of resources (e.g. battery
power) remaining on the originating peer.
The Resources TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 1 | Resources |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other
bits are not used and MUST be set to '0'.
Length - 1
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Resources - A percentage, 0-100, representing the
amount of remaining resources, such as
battery power. If resources cannot be
calculated, a value of 100 SHOULD be
reported.
10.12 Relative Link Quality Sub-TLV
The Relative Link Quality (RLQ) Sub-TLV is used in Neighbor Up,
Neighbor Update, Peer Discovery, Peer Update, and Link
Characteristics ACK messages to indicate the quality of the link
as calculated by the originating peer.
The Relative Link Quality sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 1 |Relative Link |
| | | |Quality (RLQ) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other
bits are not used and MUST be set to '0'.
Length - 1
Relative Link Quality - A non-dimensional number, 0-100,
representing relative link quality. A value
of 100 represents a link of the highest
quality. If the RLQ cannot be calculated, a
value of 100 SHOULD be reported.
10.13 Status Sub-TLV
The Status Sub-TLV is sent from either the client or server to
indicate the success or failure of a given request
The Status Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 1 | Code |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits
are not used and MUST be set to '0'.
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Length - 1
Termination Code - 0 = Success
Non-zero = Failure. Specific values of a non-
zero termination code depend on the operation
requested (e.g. Neighbor Up, Neighbor Down, etc).
10.14 Heartbeat Interval Sub-TLV
The Heartbeat Interval Sub-TLV MAY be sent from the client during
Peer Discovery to indicate the desired Heartbeat timeout window.
If included in the Peer Discovery, the server MUST either accept the
timeout interval, or reject the Peer Discovery. Failing to include
the Heartbeat Interval Sub-TLV in Peer Discovery indicates a
desire to establish the peer-to-peer DLEP session without an
activity timeout (e.g. an infinite timeout value).
The Heartbeat Interval Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 1 | Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are
not used and MUST be set to '0'.
Length - 1
Interval - 0 = Do NOT use heartbeats on this peer-to-peer
session. Non-zero = Interval, in seconds, for
heartbeat messages.
10.15 Heartbeat Threshold Sub-TLV
The Heartbeat Threshold Sub-TLV MAY be sent from the client during
Peer Discovery to indicate the desired number of windows, of time
(Heartbeat Interval) seconds, to wait before either peer declares
the peer session lost. In this case, the overall amount of time
before a peer session is declared lost is expressed as
(Interval * Threshold), where 'Interval' is the value in the
Heartbeat Interval sub-TLV, documented above. If this sub-TLV is
included by the client in the Peer Discovery, the client MUST also
specify the Heartbeat Interval sub-TLV with a non-zero interval. If
this sub-TLV is received during Peer Discovery, the server MUST
either accept the threshold, or reject the Peer Discovery. If the
Heartbeat Interval Sub-TLV is included, but this Sub-TLV is
omitted, then a threshold of '1' is assumed.
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The Heartbeat Threshold Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 1 | Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are
not used and MUST be set to '0'.
Length - 1
Threshold - 0 = Do NOT use heartbeats on this peer-to-peer
session. Non-zero = Number of windows, of
Heartbeat Interval seconds, to wait before
declaring a peer-to-peer session to be lost.
10.16 Link Characteristics ACK Timer Sub-TLV
The Link Characteristic ACK Timer Sub-TLV MAY be sent from the
client during Peer Discovery to indicate the desired number of
seconds the server should wait for a response to a Link
Characteristics Request. If this sub-TLV is received during Peer
Discovery, the server MUST either accept the timeout value, or
reject the Peer Discovery. If this Sub-TLV is omitted,
implementations SHOULD choose a default value.
The Link Characteristics ACK Timer Sub-TLV contains the
following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 1 | Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits are
not used and MUST be set to '0'.
Length - 1
Interval - 0 = Do NOT use timeouts for Link Characteristics
requests on this peer-to-peer session.
Non-zero = Interval, in seconds, to wait before
considering a Link Characteristics Request has
been lost.
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10.17 Credit Window Status Sub-TLV
The Credit Window Status Sub-TLV MUST be sent by the DLEP peer
originating a Neighbor Up message when use of credits is desired
for a given session. In the Neighbor Up message, when credits
are desired, the originating peer MUST set the value of the
window it controls (e.g. the Client Receive Window, or Server
Receive Window) to an initial, non-zero value. The peer receiving
a Neighbor Up message with a Credit Window Status Sub-TLV MUST
either reject the use of credits, via a Neighbor Up ACK response
with the correct Status Sub-TLV, or set the initial value from
the data contained in the Credit Window Status Sub-TLV. If the
initialization completes successfully, the receiving peer MUST
respond to the Neighbor Up message with a Neighbor Up ACK message
that contains a Credit Window Status Sub-TLV, initializing its
receive window.
The Credit Window Status Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 16 | Client Receive|
| | | | Window value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Client Receive Window Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Client Receive Window Value | Server Receive|
| | Window Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Server Receive Window Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Server Receive Window Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits
are not used and MUST be set to '0'.
Length - 16
Client Receive - A 64-bit unsigned number, indicating the
Window value current (or initial) number of credits
available on the Client Receive Window.
Server Receive - A 64-bit unsigned number, indicating the
Window Value current (or initial) number of credits
available on the Server Receive Window.
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10.18 Credit Grant Sub-TLV
The Credit Grant Request Sub-TLV MAY be sent from either DLEP
peer to grant an increment to credits on a window. The Credit
Grant Sub-TLV is sent as part of a Neighbor Update message. The
value in a Credit Grant Sub-TLV represents an increment to be
added to any existing credits available on the window. Upon
successful receipt and processing of a Credit Grant Sub-TLV, the
receiving peer SHOULD respond with a DLEP Neighbor Update message
containing a Credit Window Status Sub-TLV to report the updated
aggregate values for synchronization purposes.
The Credit Grant Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 8 | Credit |
| | | | Increment |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Credit Increment |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Credit Increment |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits
are not used and MUST be set to '0'.
Length - 0
Reserved - A 64-bit unsigned number representing the
additional credits to be assigned to the
credit window. Since credits can only be
granted by the receiver on a window, the
applicable credit window (either the CRW or
the SRW) is derived from the sender of the
grant. The Credit Increment MUST NOT cause
the window to overflow; if this condition
occurs, implementations MUST set the credit
window to the maximum value contained in a
64-bit quantity.
10.19 Credit Request Sub-TLV
The Credit Request Sub-TLV MAY be sent from either DLEP peer, via
a Neighbor Update order, to indicate the desire for the partner to
grant additional credits in order for data transfer to proceed on
the session. If the corresponding Neighbor Up message for this
session did NOT contain a Credit Window Status Sub-TLV, indicating
that credits are to be used on the session, then the Credit Request
Sub-TLV MUST be rejected, by sending a Neighbor Update ACK containing
a Status Sub-TLV, by the receiving peer. If credits are in use on
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the session, then the receiving peer MAY respond with a DLEP
Neighbor Update message containing a Credit Grant Sub-TLV with
an increment of credits for the session.
The Credit Request Sub-TLV contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type =TBD |TLV Flags=0x10 |Length = 0 | Reserved, MUST|
| | | | be set to 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TLV Type - TBD
TLV Flags - 0x10, Bit 3 (thasvalue) is set, all other bits
are not used and MUST be set to '0'.
Length - 0
Reserved - 0 = This field is currently unused and MUST be
set to 0.
11. DLEP Protocol Messages
DLEP places no additional requirements on the RFC 5444 Packet
formats, or the packet header. DLEP does require that the optional
'msg-seq-num' in the message header exist, and defines a set of
values for the 'tlv-type' field in the RFC 5444 TLV block. Therefore,
a DLEP message, starting from the RFC 5444 Message header, would
appear as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | |
| (value TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num | TLV block length (length of |
| | DLEP order + Sub-TLVs) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Message |TLV Flags=0x10 | Length | Start of DLEP |
| Block value | | | Sub-TLVs... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
11.1 Message Block TLV Values
As mentioned above, all DLEP messages utilize a single RFC 5444
message type, the DLEP_MESSAGE (TBD). DLEP further identifies
protocol messages by using the 'tlv-type' field in the RFC 5444
message TLV block. DLEP defines the following Message-Type-
specific values for the tlv-type field:
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TLV TLV
Value Description
=========================================
TBD Attached Peer Discovery
TBD Detached Peer Discovery
TBD Peer Offer
TBD Peer Update
TBD Peer Update ACK
TBD Peer Termination
TBD Peer Termination ACK
TBD Neighbor Up
TBD Neighbor Up ACK
TBD Neighbor Down
TBD Neighbor Down ACK
TBD Neighbor Update
TBD Neighbor Address Update
TBD Neighbor Address Update ACK
TBD Heartbeat
TBD Link Characteristics Request
TBD Link Characteristics ACK
In all of the diagrams following, the message layouts begin with the
RFC 5444 message header.
12. Peer Discovery Messages
There are two different types of Peer Discovery Messages, Attached
and Detached. Attached Peer Discovery Messages are sent by the
client when it is directly attached to the server (e.g. the client
exists as a card in the chassis, or it is connected via Ethernet with
no intervening devices). The Detached Peer Discovery message, on the
other hand, is sent by a "remote" client -- for example, a client at
a satellite hub system might use a Detached Discovery Message in
order to act as a proxy for remote ground terminals. To explain in
another way, a detached client uses the variable link itself (the
radio or satellite link) to establish a DLEP session with a remote
server.
12.1 Attached Peer Discovery Message
The Attached Peer Discovery Message is sent by an attached client
to a server to begin a new DLEP association. The Peer Offer message
is required to complete the discovery process. The client MAY
implement its own retry heuristics in the event it (the client)
determines the Attached Peer Discovery Message has timed out. An
Attached Peer Discovery Message received from a peer that is already
in session MUST be processed as if a Peer Termination Message had
been received. An implementation MAY then process the received
Attached Peer Discovery Message.
Note that metric Sub-TLVs MAY be supplied with the Peer Discovery
order. If metric Sub-TLVs are supplied, they MUST be used as a
default value for all neighbor sessions established via this peer.
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The Attached Peer Discovery Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Attached |TLV Flags=0x10 | Length =11 + | Sub-TLVs |
| Peer Discovery| | opt sub-TLVs | as noted below|
| (Value TDB) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum
bit is set). No other bits are
used and MUST be set to '0'.
Message Address Length - 0x0
Message Size - 22 + size of optional sub-TLVs
Message Sequence Number - A 16-bit unsigned integer field
containing a sequence number
generated by the message
originator.
TLV Block - TLVs Length: 14 + size of optional
sub-TLVs.
Sub-TLVs:
Identification (MANDATORY)
Version (OPTIONAL)
Peer Type (OPTIONAL)
Heartbeat Interval (OPTIONAL)
Heartbeat Threshold (OPTIONAL)
Link Characteristics ACK Timer
(OPTIONAL)
Maximum Data Rate (OPTIONAL)
Current Data Rate (OPTIONAL)
Latency (OPTIONAL)
Expected Forwarding Time (OPTIONAL)
Resources (OPTIONAL)
Relative Link Quality (OPTIONAL)
12.2 Detached Peer Discovery Message
The Detached Peer Discovery Message is sent by a detached client
proxy to a server to begin a new DLEP session. The Peer Offer
message is required to complete the discovery process. The client
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MAY implement its own retry heuristics in the event it (the client)
determines the Detached Peer Discovery Message has timed out. When
a DLEP implementation responds to a Detached Discovery Message with
a Peer Offer, the implementation MUST enter an "in session" state
with the peer. Any subsequent discovery message received from the
peer MUST be processed as if a Peer Termination Message had been
received (e.g. the existing peer session MUST be terminated). An
implementation MAY then process the received discovery message.
If metric sub-TLVs (e.g. Maximum Data Rate) are supplied with the
Detached Peer Discovery message, these metrics MUST be used as the
initial values for all far-end sessions (neighbors) established via
the peer.
The Detached Peer Discovery Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Detached |TLV Flags=0x10 | Length = 11 + | Sub-TLVs as |
| Peer Discovery| | opt sub-TLVs | noted below |
| (Value TDB) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (value TBD)
Message Flags - Set to 0x1 (bit 3,
mhasseqnum bit is set).
All other bits are not used
and MUST be set to '0'.
Message Address Length - 0x0
Message Size - 22 + size of optional
sub-TLVs
Message Sequence Number - A 16-bit unsigned integer
field containing a sequence
number, generated by the
message originator.
TLV Block - TLVs Length: 14 + size of
optional sub-TLVs.
Sub-TLVs
Identification (MANDATORY)
Version (OPTIONAL)
Peer Type (OPTIONAL)
Heartbeat Interval (OPTIONAL)
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Heartbeat Threshold (OPTIONAL)
Link Char. ACK Timer (OPTIONAL)
Maximum Data Rate (OPTIONAL)
Current Data Rate (OPTIONAL)
Latency (OPTIONAL)
Expected Forwarding Time (OPTIONAL)
Resources (OPTIONAL)
Relative Link Quality (OPTIONAL)
As in the Attached Peer Discovery, the client MAY include metric
sub-TLVs. If included, the router SHOULD use these values as defaults
that will apply to all sessions established via this client.
13. Peer Offer Message
The Peer Offer Message is sent by a server to a client in response
to a Peer Discovery Message. The Peer Offer Message is the response
to either of the Peer Discovery messages (Attached or Detached),
and completes the DLEP peer session establishment. Upon sending the
Peer Offer Message, the server then enters an "in session" state
with the client. From the client perspective, receipt and successful
parsing of a Peer Offer order MUST cause the client to enter the "in
session" state. Any subsequent Discovery messages sent or received
on this session MUST be considered an error, and the session MUST be
terminated as if a Peer Termination Message had been received.
The Peer Offer Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|DLEP Peer Offer|TLV Flags=0x10 | Length = 11 + | Sub-TLVs as |
| (Value TBD) | | opt sub-TLVs | indicated |
| | | | below |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 22 + size of optional sub-TLVs
Message Sequence Number - A 16-bit unsigned integer field containing
a sequence number, generated by the message
originator.
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TLV Block - TLV Length: 14 + size of optional sub-TLVs
Sub TLVs
Identification (MANDATORY)
Version (OPTIONAL)
Peer Type (OPTIONAL)
IPv4 Address (OPTIONAL)
IPv6 Address (OPTIONAL)
Status (OPTIONAL)
Heartbeat Interval (OPTIONAL)
Heartbeat Threshold (OPTIONAL)
Link Characteristics ACK Timer (OPTIONAL)
14. Peer Update Message
The Peer Update message is sent by a DLEP peer to indicate local
Layer 3 address changes, or for metric changes on a device-wide
basis. For example, addition of an IPv4 address to the server would
prompt a Peer Update message to its attached DLEP clients. Also, a
client that changes its Maximum Data Rate for all destinations MAY
reflect that change via a Peer Update Message to its attached server.
With Layer 3 address changes, if the client is capable of
understanding and forwarding this information, the address update
would prompt any remote DLEP clients (DLEP clients that are on the
far-end of the variable link) to issue a "Neighbor Update" message to
their local servers with the new (or deleted) addresses. Clients that
do not track Layer 3 addresses MUST silently parse and ignore the Peer
Update Message. Clients that track Layer 3 addresses MUST acknowledge
the Peer Update with a Peer Update ACK message. Servers receiving a
Peer Update with metric changes MUST apply the new metric to all
neighbor sessions established via the client. Peers MAY employ
heuristics to retransmit Peer Update messages. The sending of Peer
Update Messages for Layer 3 address changes SHOULD cease when a server
implementation determines that a client does NOT support Layer 3
address tracking.
If metric Sub-TLVs are supplied with the Peer Update message (e.g.
Maximum Data Rate), these metrics MUST be applied to all neighbor
sessions accessible via the peer.
The Peer Update Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Peer |TLV Flags=0x10 | Length = 11 + | Sub-TLVs as |
| Update | | opt sub-TLVs | noted below |
| (Value TDB) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 22 + optional Sub-TLVs
Message Sequence Number - A 16-bit unsigned integer containing a
sequence number (generated by originator).
TLV Block - TLV Length: 14 + length of optional
sub-TLVs.
Sub TLVs
Identification (MANDATORY)
IPv4 Address (OPTIONAL)
IPv6 Address (OPTIONAL)
Maximum Data Rate (OPTIONAL)
Current Data Rate (OPTIONAL)
Latency (OPTIONAL)
Expected Forwarding Time (OPTIONAL)
Resources (OPTIONAL)
Relative Link Quality (OPTIONAL)
15. Peer Update ACK Message
A peer sends the Peer Update ACK Message to indicate whether a
Peer Update Message was successfully processed.
The Peer Update ACK message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Peer |TLV Flags=0x10 | Length = 11 + | Sub-TLVs as |
| Update ACK | | opt sub-TLVs | noted below |
| (Value TDB) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
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Message Size - 22 + size of optional sub-TLVs.
Message Sequence Number - A 16-bit unsigned integer field containing
the sequence number from the Neighbor Up
Message that is being acknowledged.
TLV Block - TLV Length: 14 + optional sub-TLVs
Sub TLVs
Identification (MANDATORY)
Status (OPTIONAL)
16. Peer Termination Message
The Peer Termination Message is sent by either the client or the
server when a session needs to be terminated. Transmission of a
Peer Termination ACK message is required to confirm the
termination process. The sender of the Peer Termination message
is free to define its heuristics in event of a timeout. The
receiver of a Peer Termination Message MUST terminate all
neighbor sessions and release associated resources. State
machines are returned to the "discovery" state. No Neighbor Down
messages are sent.
The Peer Termination Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Peer |TLV Flags=0x10 | Length = 11 + | Sub-TLVs as |
| Termination | | opt sub-TLVs | noted below |
| (Value TDB) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum
bit is set). All other bits are
unused and MUST be set to '0'.
Message Address Length - 0x0
Message Size - 22 + size of optional sub-TLVs.
Message Sequence Number - A 16-bit unsigned integer field
containing a sequence number
generated by the message originator.
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TLV Block - TLV Length = 14 + optional sub-TLVs
Sub TLVs
Identification (MANDATORY)
Status (OPTIONAL)
17. Peer Termination ACK Message
The Peer Termination Message ACK is sent by a DLEP peer in response
to a received Peer Termination order.
The Peer Termination ACK Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =14 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Peer Term|TLV Flags=0x10 | Length = 11 + | Sub-TLVs as |
| ACK | | opt sub-TLVs | noted below |
| (Value TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum
bit is set). All other bits are
unused and MUST be set to '0'.
Message Address Length - 0x0
Message Size - 22 + optional sub-TLVs.
Message Sequence Number - A 16-bit unsigned integer field
containing the sequence number in
the corresponding Peer Termination
Message being acknowledged.
TLV Block - TLV Length = 14 + optional Sub-TLVs
Sub-TLVs
Identification (MANDATORY)
Status (OPTIONAL)
18. Neighbor Up Message
A peer sends the Neighbor Up message to report that a new
potential routing neighbor, or a new destination within the
network, has been detected. A Neighbor Up ACK Message is required
to confirm a received Neighbor Up. A Neighbor Up message can be
sent by a client to signal that it (the client) has detected a new
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neighbor, or by the server to indicate that new destinations
(e.g. Multicast groups) exist within the network.
The sender of the Neighbor Up Message is free to define its
retry heuristics in event of a timeout. When a Neighbor Up
message is received and successfully parsed, the receiver
should enter an "in session" state with regard to the far-end
destination, and send an acknowledgement to the originating peer.
The Neighbor Up Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 31 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =23 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Neighbor |TLV Flags=0x10 | Length =20 + | Sub-TLVs as |
| Up (TBD) | | opt sub-TLVs | noted below |
| | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 31 + optional Sub-TLVs
Message Sequence Number - A 16-bit unsigned integer field containing
a sequence number generated by the message
originator.
TLV Block - TLV Length: 23 + optional Sub-TLVs.
Sub-TLVs
Identification (MANDATORY)
MAC Address (MANDATORY)
IPv4 Address (OPTIONAL)
IPv6 Address (OPTIONAL)
Maximum Data Rate (OPTIONAL)
Current Data Rate (OPTIONAL)
Latency (OPTIONAL)
Expected Forwarding Time (OPTIONAL)
Resources (OPTIONAL)
Relative Link Factor (OPTIONAL)
Credit Window Status (OPTIONAL)
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19. Neighbor Up ACK Message
A peer sends the Neighbor Up ACK Message to indicate whether a
Neighbor Up Message was successfully processed. When a peer
receives a Neighbor Up ACK message containing a Status Sub-TLV
with a status code of 0, the receiving peer should enter an "in
session" state with respect to the far-end destination.
The Neighbor Up ACK message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 35 |
| (value TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length = 27 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Neighbor |TLV Flags=0x10 | Length = 24 | Sub-TLVs as |
| Up ACK (TBD) | | | noted below |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 35
Message Sequence Number - A 16-bit unsigned integer field containing
the sequence number from the Neighbor Down
Message that is being acknowledged.
TLV Block - TLV Length: 27
Sub-TLVs - Identification (MANDATORY)
MAC Address Sub-TLV (MANDATORY)
Status Sub-TLV (MANDATORY)
Credit Window Status (OPTIONAL)
20. Neighbor Down Message
A DLEP peer sends the Neighbor Down message to report when a
destination (a routing peer or a multicast group) is no longer
reachable. The Neighbor Down message MUST contain a MAC Address TLV.
Any other TLVs present MAY be ignored. A Neighbor Down ACK Message is
required to confirm the process. The sender of the Neighbor Down
message is free to define its retry heuristics in event of a timeout.
Upon successful receipt and parsing of a Neighbor Down message, the
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receiving peer MUST remove all state information for the destination,
and send a Neighbor Down ACK message to the originating peer.
The Neighbor Down Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 31 + optional |
| (value TBD) | | | sub-TLV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num | TLVs Length = 23 + optional |
| | Sub-TLV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TLV Type = |TLV Flags=0x10 | Length = 20 + | Sub-TLVs as |
| DLEP Neighbor | | optional Sub- | noted below |
| Down (TBD) | | TLV | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 31 + optional TLVs
Message Sequence Number - A 16-bit unsigned integer field
containing a sequence number generated
by the message originator.
TLV Block - TLV Length: 23 + optional Sub-TLVs
Sub TLVs
Identification (MANDATORY)
MAC Address (MANDATORY)
Status (OPTIONAL)
21. Neighbor Down ACK Message
A peer sends the Neighbor Down ACK Message to indicate whether
a received Neighbor Down Message was successfully processed. If
successfully processed, the sending peer MUST remove all state
information on the referenced neighbor session.
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The Neighbor Down ACK message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 35 |
| (value TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length = 27 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Neighbor |TLV Flags=0x10 | Length = 24 | Sub-TLVs as |
| Down ACK (TBD)| | | noted below |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 35
Message Sequence Number - A 16-bit unsigned integer field containing
the sequence number from the Neighbor Down
Message that is being acknowledged.
TLV Block - TLV Length: 27
Sub-TLVs - Identification (MANDATORY)
MAC Address (MANDATORY)
Status (MANDATORY)
22. Neighbor Update Message
The client sends the Neighbor Update message when a change in link
metric parameters is detected for a destination.
The Neighbor Update Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 31 + optional |
| (value TBD) | | | sub-TLV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num | TLVs Length = 23 + optional |
| | Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TLV Type = |TLV Flags=0x10 |Length = 20 + |Sub-TLVs as |
|DLEP Neighbor | |optional Sub- |noted below |
|Update (TBD) | |TLVs | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum
bit is set). All other bits are
unused and MUST be set to '0'.
Message Address Length - 0x0
Message Size - 31 + optional TLVs
Message Sequence Number - A 16-bit unsigned integer field
containing a sequence number,
generated by the message originator.
TLV Block - TLVs Length - 23 + optional Sub-TLVs.
Sub TLVs
Identification (MANDATORY)
MAC Address (MANDATORY)
Maximum Data Rate (OPTIONAL)
Current Data Rate (OPTIONAL)
Latency (OPTIONAL)
Resources (OPTIONAL)
Relative Link Quality (OPTIONAL)
Credit Window Status (OPTIONAL)
Credit Grant (OPTIONAL)
Credit Request (OPTIONAL)
23. Neighbor Address Update Message
The client sends the Neighbor Address Update message when a change
in Layer 3 addressing is detected for a neighbor session.
The Neighbor Address Update Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 31 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =23 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Neighbor |TLV Flags=0x10 | Length =20 + | Sub-TLVs as |
| Address Update| | opt sub-TLVs | noted below |
|(TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit is
set). All other bits are unused and
MUST be set to '0'.
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Message Address Length - 0x0
Message Size - 31 + optional TLVs
Message Sequence Number - A 16-bit unsigned integer field
containing a sequence number,
generated by the message originator.
TLV Block - TLVs Length - 23 + optional Sub-TLVs.
Sub TLVs
Identification Sub-TLV (MANDATORY)
MAC Address Sub-TLV (MANDATORY)
IPv4 Address Sub-TLV (OPTIONAL)
IPv6 Address Sub-TLV (OPTIONAL)
24. Neighbor Address Update ACK Message
The server sends the Neighbor Address Update ACK Message to
indicate whether a Neighbor Address Update Message was
successfully processed.
The Neighbor Address Update ACK message contains the following
fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 35 |
| (value TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length = 27 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Neighbor |TLV Flags=0x10 | Length = 24 | Sub-TLVs as |
| Address Update| | | noted below |
| ACK (TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 35
Message Sequence Number - A 16-bit unsigned integer field containing
the sequence number from the Neighbor Down
Message that is being acknowledged.
TLV Block - TLV Length: 27
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Sub TLVs
Identification Sub-TLV (MANDATORY)
MAC Address Sub-TLV (MANDATORY)
Status Sub-TLV (MANDATORY)
25. Heartbeat Message
A Heartbeat Message is sent by a peer every N seconds, where N is
defined in the "Heartbeat Interval" field of the discovery message.
The message is used by peers to detect when a DLEP session partner
is no longer communicating. Peers SHOULD allow some integral number
of heartbeat intervals (default 4) to expire with no traffic on the
session before initiating DLEP session termination procedures.
The Heartbeat Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 22 |
| (value TBD) | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length = 14 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Heartbeat|TLV Flags=0x10 | Length = 11 | Sub-TLVs as |
| (TBD) | | | noted below |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit is
set). All other bits are unused and SHOULD
be set to '0'.
Message Address Length - 0x0
Message Size - 22
Message Sequence Number - A 16-bit unsigned integer field containing
a sequence number generated by the message
originator.
TLV Block - TLV Length = 14
Sub TLVs -
Identification Sub-TLV (MANDATORY)
26. Link Characteristics Request Message
The Link Characteristics Request Message is sent by the server to
the client when the server detects that a different set of
transmission characteristics is necessary (or desired) for the
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type of traffic that is flowing on the link. It is important to
note that the link can be a logical link for a multicast session
where more than one remote neighbor participates. The request
contains either a Current Data Rate (CDR) TLV to request a different
amount of bandwidth than what is currently allocated, a Latency
TLV to request that traffic delay on the link not exceed the
specified value, or both. A Link Characteristics ACK Message is
required to complete the request. Implementations are free to
define their retry heuristics in event of a timeout. Issuing a
Link Characteristics Request with ONLY the MAC Address TLV is a
mechanism a peer MAY use to request metrics (via the Link
Characteristics ACK) from its partner.
The Link Characteristics Request Message contains the following
fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 31 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =23 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Link Char|TLV Flags=0x10 | Length =20 + | Sub-TLVs as |
| Request (TBD) | | opt sub-TLVs | noted below |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 31 + length of optional (Current Data
Rate and/or Latency) Sub-TLVs
Message Sequence Number - A 16-bit unsigned integer field containing
a sequence number generated by the message
originator.
TLV Block - Length: 23 + optional Sub-TLVs
Sub TLVs
Identification Sub-TLV (MANDATORY)
MAC Address Sub-TLV (MANDATORY)
Current Data Rate Sub-TLV - if present,
this value represents the requested data
rate in bits per second (bps). (OPTIONAL)
Latency TLV - if present, this value
represents the maximum latency, in
milliseconds, desired on the link.
(OPTIONAL)
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27. Link Characteristics ACK Message
The Link Characteristics ACK Message is sent by the client to the
server letting the server know the success (or failure) of the
requested change in link characteristics. The Link Characteristics
ACK message SHOULD contain a complete set of metric TLVs. It MUST
contain the same TLV types as the request. The values in the
metric TLVs in the Link Characteristics ACK message MUST reflect
the link characteristics after the request has been processed.
The Link Characteristics ACK Message contains the following fields:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Msg Type = |Msg Flg|AddrLen| Message Size |
| DLEP_MESSAGE | 0x1 | 0x0 | 31 + size of opt |
| (value TBD) | | | sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Seq Num |TLVs Length =23 + opt sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DLEP Link Char|TLV Flags=0x10 | Length =20 + | Sub-TLVs as |
| ACK (TBD) | | opt sub-TLVs | noted below |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Message Type - DLEP_MESSAGE (Value TBD)
Message Flags - Set to 0x1 (bit 3, mhasseqnum bit
is set). All other bits are unused and
MUST be set to '0'.
Message Address Length - 0x0
Message Size - 31 + length of optional (Current Data
Rate and/or Latency) TLVs
Message Sequence Number - A 16-bit unsigned integer field containing
the sequence number that appeared on the
corresponding Link Characteristics Request
message.
TLV Block - TLVs Length = 23 + Optional TLVs
Sub TLVs
Identification Sub-TLV (MANDATORY)
MAC Address Sub-TLV (MANDATORY)
Maximum Data Rate Sub-TLV (OPTIONAL)
Current Data Rate Sub-TLV - if present,
this value represents the NEW (or
unchanged, if the request is denied)
Current Data Rate in bits per second (bps).
(OPTIONAL)
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Latency Sub-TLV - if present, this value
represents the NEW maximum latency (or
unchanged, if the request is denied),
expressed in milliseconds, on the link.
(OPTIONAL)
Resources Sub-TLV (OPTIONAL)
Relative Link Quality Sub-TLV (OPTIONAL)
28. Security Considerations
The protocol does not contain any mechanisms for security (e.g.
authentication or encryption). The protocol assumes that any
security would be implemented in the underlying transport (for
example, by use of DTLS or some other mechanism), and is
therefore outside the scope of this document.
29. IANA Considerations
This section specifies requests to IANA.
29.1 TLV Registrations
This specification defines:
o One TLV types which must be allocated from the 0-223 range
of the "Assigned Message TLV Types" repository of [RFC5444].
o A new repository for DLEP orders, with seventeen values currently
assigned.
o A new repository for DLEP Sub-TLV assignments with nineteen values
currently assigned.
29.2 Expert Review: Evaluation Guidelines
For the registries for TLV type extensions where an Expert Review is
required, the designated expert SHOULD take the same general
recommendations into consideration as are specified by [RFC5444].
29.3 Message TLV Type Registration
The Message TLV specified below must be allocated from the "Message
TLV Types" namespace of [RFC5444].
o DLEP_MESSAGE
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29.4 DLEP Order Registration
A new repository must be created with the values of the DLEP orders.
Valid orders are:
o Attached Peer Discovery Message
o Detached Peer Discovery Message
o Peer Offer Message
o Peer Update Message
o Peer Update ACK Message
o Peer Termination Message
o Peer Termination ACK Message
o Neighbor Up Message
o Neighbor Up ACK Message
o Neighbor Down Message
o Neighbor Down ACK Message
o Neighbor Update Message
o Neighbor Address Update Message
o Neighbor Address Update ACK Message
o Heartbeat Message
o Link Characteristics Request Message
o Link Characteristics ACK Message
This registry should be created according to the guidelines for
'Message-Type-Specific TLV' registration as specified in section
6.2.1 of [RFC5444].
29.5 DLEP Sub-TLV Type Registrations
A new repository for DLEP Sub-TLVs must be created. Valid Sub-TLVs are:
o Identification Sub-TLV
o DLEP Version Sub-TLV
o Peer Type Sub-TLV
o MAC Address Sub-TLV
o IPv4 Address Sub-TLV
o IPv6 Address Sub-TLV
o Maximum Data Rate Sub-TLV
o Current Data Rate Sub-TLV
o Latency Sub-TLV
o Expected Forwarding Time Sub-TLV
o Resources Sub-TLV
o Relative Link Quality Sub-TLV
o Status Sub-TLV
o Heartbeat Interval Sub-TLV
o Heartbeat Threshold Sub-TLV
o Link Characteristics ACK Timer Sub-TLV
o Credit Window Status Sub-TLV
o Credit Grant Sub-TLV
o Credit Request Sub-TLV
It is also requested that the registry allocation contain space
reserved for experimental sub-TLVs.
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30. Appendix A.
Peer Level Message Flows
*Modem Device (Client) Restarts Discovery
Server Client Message Description
====================================================================
<-------Peer Discovery--------- Client initiates discovery
---------Peer Offer-----------> Server detects a problem, sends
w/ Non-zero Status TLV Peer Offer w/ Status TLV indicating
the error.
Client accepts failure, restarts
discovery process.
<-------Peer Discovery--------- Client initiates discovery
---------Peer Offer-----------> Server accepts, sends Peer Offer
w/ Zero Status TLV w/ Status TLV indicating success.
Discovery completed.
*Modem Device Detects Peer Offer Timeout
Server Client Message Description
====================================================================
<-------Peer Discovery--------- Client initiates discovery,
starts a guard timer.
Client guard timer expires.
Client restarts discovery process.
<-------Peer Discovery--------- Client initiates discovery,
starts a guard timer.
---------Peer Offer-----------> Server accepts, sends Peer Offer
w/ Zero Status TLV w/ Status TLV indicating success.
Discovery completed.
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*Server Peer Offer Lost
Server Client Message Description
====================================================================
<-------Peer Discovery--------- Client initiates discovery,
starts a guard timer.
---------Peer Offer-------|| Server offers availability
Client times out on Peer Offer,
restarts discovery process.
<-------Peer Discovery--------- Client initiates discovery
---------Peer Offer-----------> Server detects subsequent discovery,
internally terminates the previous,
accepts the new association, sends
Peer Offer w/ Status TLV indicating
success.
Discovery completed.
*Discovery Success
Server Client Message Description
====================================================================
<-------Peer Discovery--------- Client initiates discovery
---------Peer Offer-----------> Server offers availability
-------Peer Heartbeat--------->
<-------Peer Heartbeat---------
-------Peer Heartbeat--------->
<==============================> Neighbor Sessions
<-------Peer Heartbeat---------
-------Peer Heartbeat--------->
--------Peer Term Req---------> Terminate Request
<--------Peer Term Res--------- Terminate Response
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*Server Detects a Heartbeat timeout
Server Client Message Description
====================================================================
<-------Peer Heartbeat---------
-------Peer Heartbeat--------->
||---Peer Heartbeat---------
~ ~ ~ ~ ~ ~ ~
-------Peer Heartbeat--------->
||---Peer Heartbeat---------
Server Heartbeat Timer expires,
detects missing heartbeats. Server
takes down all neighbor sessions
and terminates the Peer association.
------Peer Terminate ---------> Peer Terminate Request
Client takes down all neighbor
sessions, then acknowledges the
Peer Terminate
<----Peer Terminate ACK--------- Peer Terminate ACK
*Client Detects a Heartbeat timeout
Server Client Message Description
====================================================================
<-------Peer Heartbeat---------
-------Peer Heartbeat------||
<-------Peer Heartbeat---------
~ ~ ~ ~ ~ ~ ~
-------Peer Heartbeat------||
<-------Peer Heartbeat---------
Client Heartbeat Timer expires,
detects missing heartbeats. Modem
takes down all neighbor sessions
and terminates the Peer association.
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<-------Peer Terminate-------- Peer Terminate Request
Server takes down all neighbor
sessions, then acknowledges the
Peer Terminate
------Peer Terminate ACK-----> Peer Terminate ACK
*Peer Terminate (from Client) Lost
Server Client Message Description
====================================================================
||------Peer Terminate-------- Client Peer Terminate Request
Server Heartbeat times out,
terminates association.
--------Peer Terminate-------> Server Peer Terminate
<-----Peer Terminate ACK------ Client sends Peer Terminate ACK
*Peer Terminate (from server) Lost
Server Client Message Description
====================================================================
-------Peer Terminate--------> Server Peer Terminate Request
Client HB times out,
terminates association.
<------Peer Terminate-------- Client Peer Terminate
------Peer Terminate ACK-----> Peer Terminate ACK
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Neighbor Level Message Flows
*Client Neighbor Up Lost
Server Client Message Description
====================================================================
||-----Neighbor Up ------------ Client sends Neighbor Up
Client timesout on ACK
<------Neighbor Up ------------ Client sends Neighbor Up
------Neighbor Up ACK---------> Server accepts the neighbor
session
<------Neighbor Update--------- Client Neighbor Metrics
. . . . . . . .
<------Neighbor Update--------- Client Neighbor Metrics
*Server Detects Duplicate Neighbor Ups
Server Client Message Description
====================================================================
<------Neighbor Up ------------ Client sends Neighbor Up
------Neighbor Up ACK-------|| Server accepts the neighbor
session
Client timesout on ACK
<------Neighbor Up ------------ Client resends Neighbor Up
Server detects duplicate
Neighbor, takes down the
previous, accepts the new
Neighbor.
------Neighbor Up ACK---------> Server accepts the neighbor
session
<------Neighbor Update--------- Client Neighbor Metrics
. . . . . . . .
<------Neighbor Update--------- Client Neighbor Metrics
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*Neighbor Up, No Layer 3 Addresses
Server Client Message Description
====================================================================
<------Neighbor Up ------------ Client sends Neighbor Up
------Neighbor Up ACK---------> Server accepts the neighbor
session
Server ARPs for IPv4 if defined.
Server drives ND for IPv6 if
defined.
<------Neighbor Update--------- Client Neighbor Metrics
. . . . . . . .
<------Neighbor Update--------- Client Neighbor Metrics
*Neighbor Up with IPv4, No IPv6
Server Client Message Description
====================================================================
<------Neighbor Up ------------ Client sends Neighbor Up with
the IPv4 TLV
------Neighbor Up ACK---------> Server accepts the neighbor
session
Server drives ND for IPv6 if
defined.
<------Neighbor Update--------- Client Neighbor Metrics
. . . . . . . .
<------Neighbor Update--------- Client Neighbor Metrics
*Neighbor Up with IPv4 and IPv6
Server Client Message Description
====================================================================
<------Neighbor Up ------------ Client sends Neighbor Up with
the IPv4 and IPv6 TLVs
------Neighbor Up ACK---------> Server accepts the neighbor
session
<------Neighbor Update--------- Client Neighbor Metrics
. . . . . . . .
<------Neighbor Update--------- Client Neighbor Metrics
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*Neighbor Session Success
Server Client Message Description
====================================================================
---------Peer Offer-----------> Server offers availability
-------Peer Heartbeat--------->
<------Neighbor Up ----------- Client
------Neighbor Up ACK--------> Server
<------Neighbor Update--------- Client
. . . . . . . .
<------Neighbor Update--------- Client
Client initiates the terminate
<------Neighbor Down ---------- Client
------Neighbor Down ACK-------> Server
or
Server initiates the terminate
------Neighbor Down ----------> Server
<------Neighbor Down ACK------- Client
Acknowledgements
The authors would like to acknowledge the influence and contributions
of Chris Olsen, Teco Boot, Subir Das, Jaewon Kang, Vikram Kaul, Rick
Taylor, and John Dowdell.
Normative References
[RFC5444] Clausen, T., Ed,. "Generalized Mobile Ad Hoc Network (MANET)
Packet/Message Format", RFC 5444, Februar, 2009.
[RFC5578] Berry, B., Ed., "PPPoE with Credit Flow and Metrics",
RFC 5578, February 2010.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, March 1997.
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Informative References
[DTLS] Rescorla, E., Ed,. "Datagram Transport Layer Security",
RFC 4347, April 2006.
Author's Addresses
Stan Ratliff
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
EMail: sratliff@cisco.com
Bo Berry
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
EMail: boberry@cisco.com
Greg Harrison
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
EMail: greharri@cisco.com
Shawn Jury
NetApp
7301 Kit Creek Road, Building 2
Research Triangle Park, NC 27709
USA
Email: shawn.jury@netapp.com
Darryl Satterwhite
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
Email: dsatterw@cisco.com
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