Network Working Group G. Mirsky Internet-Draft X. Min Intended status: Standards Track ZTE Corp. Expires: May 3, 2020 H. Nydell Accedian Networks R. Foote Nokia A. Masputra Apple Inc. E. Ruffini OutSys October 31, 2019 Simple Two-way Active Measurement Protocol Optional Extensions draft-ietf-ippm-stamp-option-tlv-02 Abstract This document describes optional extensions to Simple Two-way Active Measurement Protocol (STAMP) which enable measurement performance metrics in addition to ones supported by the STAMP base specification. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on May 3, 2020. Copyright Notice Copyright (c) 2019 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 Mirsky, et al. Expires May 3, 2020 [Page 1] Internet-Draft STAMP Extensions October 2019 (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions used in this document . . . . . . . . . . . . . . 3 2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 3. Theory of Operation . . . . . . . . . . . . . . . . . . . . . 3 4. TLV Extensions to STAMP . . . . . . . . . . . . . . . . . . . 4 4.1. Extra Padding TLV . . . . . . . . . . . . . . . . . . . . 6 4.2. Location TLV . . . . . . . . . . . . . . . . . . . . . . 6 4.3. Timestamp Information TLV . . . . . . . . . . . . . . . . 8 4.4. Class of Service TLV . . . . . . . . . . . . . . . . . . 9 4.5. Direct Measurement TLV . . . . . . . . . . . . . . . . . 10 4.6. Access Report TLV . . . . . . . . . . . . . . . . . . . . 11 4.7. Follow-up Telemetry TLV . . . . . . . . . . . . . . . . . 13 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 5.1. STAMP TLV Registry . . . . . . . . . . . . . . . . . . . 14 5.2. Synchronization Source Sub-registry . . . . . . . . . . . 15 5.3. Timestamping Method Sub-registry . . . . . . . . . . . . 16 5.4. Access ID Sub-registry . . . . . . . . . . . . . . . . . 17 5.5. Return Code Sub-registry . . . . . . . . . . . . . . . . 17 6. Security Considerations . . . . . . . . . . . . . . . . . . . 18 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 18 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 19 9.1. Normative References . . . . . . . . . . . . . . . . . . 19 9.2. Informative References . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20 1. Introduction Simple Two-way Active Measurement Protocol (STAMP) [I-D.ietf-ippm-stamp] supports the use of optional extensions that use Type-Length-Value (TLV) encoding. Such extensions are to enhance the STAMP base functions, such as measurement of one-way and round- trip delay, latency, packet loss, as well as ability to detect packet duplication and out-of-order delivery of the test packets. This specification provides definitions of optional STAMP extensions, their formats, and theory of operation. Mirsky, et al. Expires May 3, 2020 [Page 2] Internet-Draft STAMP Extensions October 2019 2. Conventions used in this document 2.1. Terminology STAMP - Simple Two-way Active Measurement Protocol DSCP - Differentiated Services Code Point ECN - Explicit Congestion Notification NTP - Network Time Protocol PTP - Precision Time Protocol HMAC Hashed Message Authentication Code TLV Type-Length-Value BITS Building Integrated Timing Supply SSU Synchronization Supply Unit GPS Global Positioning System GLONASS Global Orbiting Navigation Satellite System LORAN-C Long Range Navigation System Version C MBZ Must Be Zeroed CoS Class of Service PMF Performance Measurement Function 2.2. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 3. Theory of Operation STAMP Session-Sender transmits test packets to STAMP Session- Reflector. STAMP Session-Reflector receives Session-Sender's packet and acts according to the configuration and optional control information communicated in the Session-Sender's test packet. STAMP Mirsky, et al. Expires May 3, 2020 [Page 3] Internet-Draft STAMP Extensions October 2019 defines two different test packet formats, one for packets transmitted by the STAMP-Session-Sender and one for packets transmitted by the STAMP-Session-Reflector. STAMP supports two modes: unauthenticated and authenticated. Unauthenticated STAMP test packets are compatible on the wire with unauthenticated TWAMP-Test [RFC5357] packet formats. By default, STAMP uses symmetrical packets, i.e., the size of the packet transmitted by Session-Reflector equals the size of the packet received by the Session-Reflector. 4. TLV Extensions to STAMP Figure 1 displays the format of STAMP Session-Sender test packet in unauthenticated mode that includes a TLV. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Error Estimate | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | | | | MBZ (30 octets) | | | | | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Value ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: STAMP Session-Sender test packet format with TLV in unauthenticated mode The MBZ (Must Be Zeroed) field of a test packet transmitted by a STAMP Session-Sender MUST be 30 octets long. A STAMP Session-Sender test packet MUST NOT use the Reflect Octets capability defined in [RFC6038]. Mirsky, et al. Expires May 3, 2020 [Page 4] Internet-Draft STAMP Extensions October 2019 TLVs (Type-Length-Value tuples) have the two octets long Type field, two octets long Length field that is the length of the Value field in octets. Type values, see Section 5.1, less than 32768 identify mandatory TLVs that MUST be supported by an implementation. Type values greater than or equal to 32768 identify optional TLVs that SHOULD be ignored if the implementation does not understand or support them. If a Type value for TLV or sub-TLV is in the range for Vendor Private Use, the Length MUST be at least 4, and the first four octets MUST be that vendor's the Structure of Management Information (SMI) Private Enterprise Number, in network octet order. The rest of the Value field is private to the vendor. Following sections describe the use of TLVs for STAMP that extend STAMP capability beyond its base specification. Figure 2 displays the format of STAMP Session-Reflector test packet in unauthenticated mode that includes a TLV. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Error Estimate | MBZ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Receive Timestamp | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session-Sender Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session-Sender Timestamp | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session-Sender Error Estimate | MBZ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Ses-Sender TTL | MBZ2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Value ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: STAMP Session-Reflector test packet format with TLV in unauthenticated mode Mirsky, et al. Expires May 3, 2020 [Page 5] Internet-Draft STAMP Extensions October 2019 The MBZ2 field of a test packet transmitted by a STAMP Session- Reflector MUST be 3 octets long. A STAMP node, whether Session-Sender or Session-Reflector, receiving a test packet MUST determine whether the packet is a base STAMP packet or includes one or more TLVs. The node MUST compare the value in the Length field of the UDP header and the length of the base STAMP test packet in the mode, unauthenticated or authenticated based on the configuration of the particular STAMP test session. If the difference between the two values is larger than the length of UDP header, then the test packet includes one or more STAMP TLVs that immediately follow the base STAMP test packet. 4.1. Extra Padding TLV 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extra Padding Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Extra Padding ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: Extra Padding TLV where fields are defined as the following: o Extra Padding Type - TBA1 allocated by IANA Section 5.1 o Length - two octets long field equals length on the Extra Padding field in octets. o Extra Padding - a pseudo-random sequence of numbers. The field MAY be filled with all zeroes. The Extra Padding TLV is similar to the Packet Padding field in TWAMP-Test packet [RFC5357]. The in STAMP the Packet Padding field is used to ensure symmetrical size between Session-Sender and Session-Reflector test packets. Extra Padding TLV MUST be used to create STAMP test packets of larger size. 4.2. Location TLV STAMP session-sender MAY include the Location TLV to request information from the session-reflector. The session-sender SHOULD NOT fill any information fields except for Type and Length. The Mirsky, et al. Expires May 3, 2020 [Page 6] Internet-Draft STAMP Extensions October 2019 session-reflector MUST validate the Length value against the address family of the transport encapsulating the STAMP test packet. If the value of the Length field is invalid, the session-reflector MUST zero all fields and MUST NOT return any information to the session-sender. The session-reflector MUST ignore all other fields of the received Location TLV. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Location Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Source MAC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | Reserved A | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Destination IP Address ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Source IP Address ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Dest.port | Src.Port | Reserved B | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4: Session-Reflector Location TLV where fields are defined as the following: o Location Type - TBA2 allocated by IANA Section 5.1 o Length - two octets long field equals length on the Value field in octets. Length field value MUST be 20 octets for the IPv4 address family. For the IPv6 address family value of the Length field MUST be 44 octets. All other values are invalid. o Source MAC - 6 octets 48 bits long field. The session-reflector MUST copy Source MAC of received STAMP packet into this field. o Reserved A - two octets long field. MUST be zeroed on transmission and ignored on reception. o Destination IP Address - IPv4 or IPv6 destination address of the received by the session-reflector STAMP packet. o Source IP Address - IPv4 or IPv6 source address of the received by the session-reflector STAMP packet. o Dest.port - one octet long UDP destination port number of the received STAMP packet. Mirsky, et al. Expires May 3, 2020 [Page 7] Internet-Draft STAMP Extensions October 2019 o Src.port - one octet long UDP source port number of the received STAMP packet. o Reserved B - two octets long field. MUST be zeroed on transmission and ignored on reception. The Location TLV MAY be used to determine the last-hop addressing for STAMP packets including source and destination IP addresses as well as the MAC address of the last-hop router. Last-hop MAC address MAY be monitored by the Session-Sender whether there has been a path switch on the last hop, closest to the Session-Reflector. The IP addresses and UDP port will indicate if there is a NAT router on the path, and allows the Session-Sender to identify the IP address of the Session-Reflector behind the NAT, detect changes in the NAT mapping that could cause sending the STAMP packets to the wrong Session- Reflector. 4.3. Timestamp Information TLV STAMP session-sender MAY include the Timestamp Information TLV to request information from the session-reflector. The session-sender SHOULD NOT fill any information fields except for Type and Length. The session-reflector MUST validate the Length value of the STAMP test packet. If the value of the Length field is invalid, the session-reflector MUST zero all fields and MUST NOT return any information to the session-sender. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp Information Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sync. Src In | Timestamp In | Sync. Src Out | Timestamp Out | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5: Timestamp Information TLV where fields are defined as the following: o Timestamp Information Type - TBA3 allocated by IANA Section 5.1 o Length - two octets long field, equals four octets. o Sync Src In - one octet long field that characterizes the source of clock synchronization at the ingress of Session-Reflector. There are several of methods to synchronize the clock, e.g., Network Time Protocol (NTP) [RFC5905], Precision Time Protocol (PTP) [IEEE.1588.2008], Synchronization Supply Unit (SSU) or Mirsky, et al. Expires May 3, 2020 [Page 8] Internet-Draft STAMP Extensions October 2019 Building Integrated Timing Supply (BITS), or Global Positioning System (GPS), Global Orbiting Navigation Satellite System (GLONASS) and Long Range Navigation System Version C (LORAN-C). The value is one of the listed in Table 4. o Timestamp In - one octet long field that characterizes the method by which the ingress of Session-Reflector obtained the timestamp T2. A timestamp may be obtained with hardware assist, via software API from a local wall clock, or from a remote clock (the latter referred to as "control plane"). The value is one of the listed in Table 6. o Sync Src Out - one octet long field that characterizes the source of clock synchronization at the egress of Session-Reflector. The value is one of the listed in Table 4. o Timestamp Out - one octet long field that characterizes the method by which the egress of Session-Reflector obtained the timestamp T3. The value is one of the listed in Table 6. 4.4. Class of Service TLV The STAMP session-sender MAY include Class of Service (CoS) TLV in the STAMP test packet. If the CoS TLV is present in the STAMP test packet and the value of the DSCP1 field is zero, then the STAMP session-reflector MUST copy the values of Differentiated Services Code Point (DSCP) ECN fields from the received STAMP test packet into DSCP2 and ECN fields respectively of the CoS TLV of the reflected STAMP test packet. If the value of the DSCP1 field is non-zero, then the STAMP session-reflector MUST use DSCP1 value from the CoS TLV in the received STAMP test packet as DSCP value of STAMP reflected test packet and MUST copy DSCP and ECN values of the received STAMP test packet into DSCP2 and ECN fields of Class of Service TLV in the STAMP reflected a packet. The Session-Sender, upon receiving the reflected packet, will save the DSCP and ECN values for analysis of the CoS in the reverse direction. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Class of Service Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DSCP1 | DSCP2 |ECN| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 6: Class of Service TLV where fields are defined as the following: Mirsky, et al. Expires May 3, 2020 [Page 9] Internet-Draft STAMP Extensions October 2019 o Class of Service Type - TBA4 allocated by IANA Section 5.1 o Length - two octets long field, equals four octets. o DSCP1 - The Differentiated Services Code Point (DSCP) intended by the Session-Sender. To be used as the return DSCP from the Session-Reflector. o DSCP2 - The received value in the DSCP field at the Session- Reflector in the forward direction. o ECN - The received value in the ECN field at the Session-Reflector in the forward direction. o Reserved - 18 bits long field, must be zeroed in transmission and ignored on receipt. A STAMP Session-Sender that includes the CoS TLV sets the value of the DSCP1 field and zeroes the value of the DSCP2 field. A STAMP Session-Reflector that received the test packet with the CoS TLV MUST include the CoS TLV in the reflected test packet. Also, the Session- Reflector MUST copy the value of the DSCP field of the IP header of the received STAMP test packet into the DSCP2 field in the reflected test packet. And, at last, the Session-Reflector MUST set the value of the DSCP field in the IP header of the reflected test packet equal to the value of the DSCP1 field of the test packet it has received. Re-mapping of CoS in some use cases, for example, in mobile backhaul networks is used to provide multiple services, i.e., 2G, 3G, LTE, over the same network. But if it is misconfigured, then it is often difficult to diagnose the root cause of the problem that is viewed as an excessive packet drop of higher level service while packet drop for lower service packets is at a normal level. Using CoS TLV in STAMP test helps to troubleshoot the existing problem and also verify whether DiffServ policies are processing CoS as required by the configuration. 4.5. Direct Measurement TLV The Direct Measurement TLV enables collection of "in profile" IP packets that had been transmitted and received by the Session-Sender and Session-Reflector respectfully. The definition of "in-profile packet" is outside the scope of this document. Mirsky, et al. Expires May 3, 2020 [Page 10] Internet-Draft STAMP Extensions October 2019 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Direct Measurement Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session-Sender Tx counter (S_TxC) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session-Reflector Rx counter (R_RxC) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session-Reflector Tx counter (R_TxC) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 7: Direct Measurement TLV where fields are defined as the following: o Direct Measurement Type - TBA5 allocated by IANA Section 5.1 o Length - two octets long field equals length on the Value field in octets. Length field value MUST be 12 octets. o Session-Sender Tx counter (S_TxC) is four octets long field. o Session-Reflector Rx counter (R_RxC) is four octets long field. MUST be zeroed by the Session-Sender and filled by the Session- Reflector. o Session-Reflector Tx counter (R_TxC) is four octets long field. MUST be zeroed by the Session-Sender and filled by the Session- Reflector. 4.6. Access Report TLV A STAMP Session-Sender MAY include Access Report TLV (Figure 8) to indicate changes to the access network status to the Session- Reflector. The definition of an access network is outside the scope of this document. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Access Report Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Access ID | Return Code | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 8: Access Report TLV Mirsky, et al. Expires May 3, 2020 [Page 11] Internet-Draft STAMP Extensions October 2019 where fields are defined as follows: o Access Report Type - TBA6 allocated by IANA Section 5.1. o Length - two octets long field, equals four octets. o Access ID - one octet long field that identifies the access network, e.g., 3GPP (Radio Access Technologies specified by 3GPP) or Non-3GPP (accesses that are not specified by 3GPP) [TS23501]. The value is one of Section 5.4. o Return Code - one octet long field that identifies the report signal, e.g., available, unavailable. The value is one of Section 5.5. o Reserved - two octets long field, must be zeroed on transmission and ignored on receipt. The STAMP Session-Sender that includes the Access Report TLV sets the value of the Access ID field according to the type of access network it reports on. Also, the Session-Sender sets the value of the Return Code field to reflect the operational state of the access network. The mechanism to determine the state of the access network is outside the scope of this specification. A STAMP Session-Reflector that received the test packet with the Access Report TLV MUST include the Access Report TLV in the reflected test packet. The Session- Reflector MUST set the value of the Access ID and Return Code fields equal to the values of the corresponding fields from the test packet it has received. The Session-Sender MUST also arm a retransmission timer after sending a test packet that includes the Access Report TLV. This timer MUST be disarmed upon the reception of the reflected STAMP test packet that includes Access Report TLV. In the event the timer expires before such a packet is received, the Session-Sender MUST retransmit the STAMP test packet that contains the Access Report TLV. This retransmission SHOULD be repeated up to four times before the procedure is aborted. Setting the value for the retransmission timer is based on local policies, network environment. The default value of the retransmission timer for Access Report TLV SHOULD be three seconds. An implementation MUST provide control of the retransmission timer value and the number of retransmissions. The Access Report TLV is used by the Performance Measurement Function (PMF) components of the Access Steering, Switching and Splitting feature for 5G networks [TS23501]. The PMF component in the User Equipment acts as the STAMP Session-Sender, and the PMF component in the User Plane Function acts as the STAMP Session-Reflector. Mirsky, et al. Expires May 3, 2020 [Page 12] Internet-Draft STAMP Extensions October 2019 4.7. Follow-up Telemetry TLV A Session-Reflector might be able to put in the Timestamp field only a "SW Local" (see Table 6) timestamp. But the hosting system might provide the timestamp closer to the start of actual packet transmission even though when it is not possible to deliver the information to the Session-Sender in the packet itself. This timestamp might nevertheless be important for the Session-Sender, as it helps in to improve the accuracy of measuring network delay by minimizing the impact of egress queuing delays on the measurement. A STAMP Session-Sender MAY include the Follow-up Telemetry TLV to request information from the Session-Reflector. The Session-Sender MUST set the Follow-up Telemetry Type and Length fields to their appropriate values. Sequence Number and Timestamp fields MUST be zeroed on transmission by the Session-Sender and ignored by the Session-Reflector upon receipt of the STAMP test packet that includes the Follow-up Telemetry TLV. The Session-Reflector MUST validate the Length value of the STAMP test packet. If the value of the Length field is invalid, the Session-Reflector MUST zero Sequence Number and Timestamp fields. If the Session-Reflector is in stateless mode (defined in Section 4.2 [I-D.ietf-ippm-stamp]), it MUST zero Sequence Number and Timestamp 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Follow-up Telemetry Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp M | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 9: Follow-up Telemetry TLV where fields are defined as follows: o Follow-up Telemetry Type - TBA7 allocated by IANA Section 5.1. o Length - two octets long field, equals 12 octets. o Sequence Number - four octets long field indicating the sequence number of the last packet reflected in the same STAMP-test session. Since the Session-Reflector runs in the stateful mode Mirsky, et al. Expires May 3, 2020 [Page 13] Internet-Draft STAMP Extensions October 2019 (defined in Section 4.2 [I-D.ietf-ippm-stamp]), it is the Session- Reflector's Sequence Number of the previous reflected packet. o Timestamp - eight octets long field, with the format indicated by the Z flag of the Error Estimate field as described in Section 4.1 [I-D.ietf-ippm-stamp]. It carries the timestamp when the reflected packet with the specified sequence number was sent.. o Timestamp M(ode) - one octet long field that characterizes the method by which the entity that transmits a reflected STAMP packet obtained the timestamp. The value is one of the listed in Table 6. o Reserved - the field MUST be zeroed on transmission and ignored on receipt. 5. IANA Considerations 5.1. STAMP TLV Registry IANA is requested to create the STAMP TLV Type registry. All code points in the range 1 through 32759 in this registry shall be allocated according to the "IETF Review" procedure as specified in [RFC8126]. Code points in the range 32760 through 65279 in this registry shall be allocated according to the "First Come First Served" procedure as specified in [RFC8126]. Remaining code points are allocated according to Table 1: +---------------+-------------------------+-------------------------+ | Value | Description | Reference | +---------------+-------------------------+-------------------------+ | 0 | Reserved | This document | | 1- 32767 | Mandatory TLV, | IETF Review | | | unassigned | | | 32768 - 65279 | Optional TLV, | First Come First Served | | | unassigned | | | 65280 - 65519 | Experimental | This document | | 65520 - 65534 | Private Use | This document | | 65535 | Reserved | This document | +---------------+-------------------------+-------------------------+ Table 1: STAMP TLV Type Registry This document defines the following new values in the STAMP TLV Type registry: Mirsky, et al. Expires May 3, 2020 [Page 14] Internet-Draft STAMP Extensions October 2019 +-------+-----------------------+---------------+ | Value | Description | Reference | +-------+-----------------------+---------------+ | TBA1 | Extra Padding | This document | | TBA2 | Location | This document | | TBA3 | Timestamp Information | This document | | TBA4 | Class of Service | This document | | TBA6 | Access Report | This document | | TBA7 | Follow-up Telemetry | This document | +-------+-----------------------+---------------+ Table 2: STAMP Types 5.2. Synchronization Source Sub-registry IANA is requested to create Synchronization Source sub-registry as part of STAMP TLV Type registry. All code points in the range 1 through 127 in this registry shall be allocated according to the "IETF Review" procedure as specified in [RFC8126]. Code points in the range 128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as specified in [RFC8126]. Remaining code points are allocated according to Table 1: +-----------+--------------+-------------------------+ | Value | Description | Reference | +-----------+--------------+-------------------------+ | 0 | Reserved | This document | | 1- 127 | Unassigned | IETF Review | | 128 - 239 | Unassigned | First Come First Served | | 240 - 249 | Experimental | This document | | 250 - 254 | Private Use | This document | | 255 | Reserved | This document | +-----------+--------------+-------------------------+ Table 3: Synchronization Source Sub-registry This document defines the following new values in the Synchronization Source sub-registry: Mirsky, et al. Expires May 3, 2020 [Page 15] Internet-Draft STAMP Extensions October 2019 +-------+---------------------+---------------+ | Value | Description | Reference | +-------+---------------------+---------------+ | 1 | NTP | This document | | 2 | PTP | This document | | 3 | SSU/BITS | This document | | 4 | GPS/GLONASS/LORAN-C | This document | | 5 | Local free-running | This document | +-------+---------------------+---------------+ Table 4: Synchronization Sources 5.3. Timestamping Method Sub-registry IANA is requested to create Timestamping Method sub-registry as part of STAMP TLV Type registry. All code points in the range 1 through 127 in this registry shall be allocated according to the "IETF Review" procedure as specified in [RFC8126]. Code points in the range 128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as specified in [RFC8126]. Remaining code points are allocated according to Table 1: +-----------+--------------+-------------------------+ | Value | Description | Reference | +-----------+--------------+-------------------------+ | 0 | Reserved | This document | | 1- 127 | Unassigned | IETF Review | | 128 - 239 | Unassigned | First Come First Served | | 240 - 249 | Experimental | This document | | 250 - 254 | Private Use | This document | | 255 | Reserved | This document | +-----------+--------------+-------------------------+ Table 5: Timestamping Method Sub-registry This document defines the following new values in the Timestamping Methods sub-registry: +-------+---------------+---------------+ | Value | Description | Reference | +-------+---------------+---------------+ | 1 | HW Assist | This document | | 2 | SW local | This document | | 3 | Control plane | This document | +-------+---------------+---------------+ Table 6: Timestamping Methods Mirsky, et al. Expires May 3, 2020 [Page 16] Internet-Draft STAMP Extensions October 2019 5.4. Access ID Sub-registry IANA is requested to create Access ID sub-registry as part of STAMP TLV Type registry. All code points in the range 1 through 127 in this registry shall be allocated according to the "IETF Review" procedure as specified in [RFC8126]. Code points in the range 128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as specified in [RFC8126]. Remaining code points are allocated according to Table 7: +-----------+--------------+-------------------------+ | Value | Description | Reference | +-----------+--------------+-------------------------+ | 0 | Reserved | This document | | 1- 127 | Unassigned | IETF Review | | 128 - 239 | Unassigned | First Come First Served | | 240 - 249 | Experimental | This document | | 250 - 254 | Private Use | This document | | 255 | Reserved | This document | +-----------+--------------+-------------------------+ Table 7: Access ID Sub-registry This document defines the following new values in the Access ID sub- registry: +-------+-------------+---------------+ | Value | Description | Reference | +-------+-------------+---------------+ | 1 | 3GPP | This document | | 2 | Non-3GPP | This document | +-------+-------------+---------------+ Table 8: Access IDs 5.5. Return Code Sub-registry IANA is requested to create Return Code sub-registry as part of STAMP TLV Type registry. All code points in the range 1 through 127 in this registry shall be allocated according to the "IETF Review" procedure as specified in [RFC8126]. Code points in the range 128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as specified in [RFC8126]. Remaining code points are allocated according to Table 7: Mirsky, et al. Expires May 3, 2020 [Page 17] Internet-Draft STAMP Extensions October 2019 +-----------+--------------+-------------------------+ | Value | Description | Reference | +-----------+--------------+-------------------------+ | 0 | Reserved | This document | | 1- 127 | Unassigned | IETF Review | | 128 - 239 | Unassigned | First Come First Served | | 240 - 249 | Experimental | This document | | 250 - 254 | Private Use | This document | | 255 | Reserved | This document | +-----------+--------------+-------------------------+ Table 9: Return Code Sub-registry This document defines the following new values in the Return Code sub-registry: +-------+---------------------+---------------+ | Value | Description | Reference | +-------+---------------------+---------------+ | 1 | Network available | This document | | 2 | Network unavailable | This document | +-------+---------------------+---------------+ Table 10: Return Codes 6. Security Considerations Use of HMAC in authenticated mode may be used to simultaneously verify both the data integrity and the authentication of the STAMP test packets. 7. Acknowledgments Authors much appreciate the thorough review and thoughful comments received from Tianran Zhou. 8. Contributors The following people contributed text to this document: Guo Jun ZTE Corporation 68# Zijinghua Road Nanjing, Jiangsu 210012 P.R.China Phone: +86 18105183663 Email: guo.jun2@zte.com.cn Mirsky, et al. Expires May 3, 2020 [Page 18] Internet-Draft STAMP Extensions October 2019 9. References 9.1. Normative References [I-D.ietf-ippm-stamp] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple Two-way Active Measurement Protocol", draft-ietf-ippm- stamp-09 (work in progress), October 2019. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J. Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)", RFC 5357, DOI 10.17487/RFC5357, October 2008, . [RFC6038] Morton, A. and L. Ciavattone, "Two-Way Active Measurement Protocol (TWAMP) Reflect Octets and Symmetrical Size Features", RFC 6038, DOI 10.17487/RFC6038, October 2010, . [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 8126, DOI 10.17487/RFC8126, June 2017, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 9.2. Informative References [IEEE.1588.2008] "Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems", IEEE Standard 1588, March 2008. [RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch, "Network Time Protocol Version 4: Protocol and Algorithms Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010, . Mirsky, et al. Expires May 3, 2020 [Page 19] Internet-Draft STAMP Extensions October 2019 [TS23501] 3GPP (3rd Generation Partnership Project), "Technical Specification Group Services and System Aspects; System Architecture for the 5G System; Stage 2 (Release 16)", 3GPP TS23501, 2019. Authors' Addresses Greg Mirsky ZTE Corp. Email: gregimirsky@gmail.com Xiao Min ZTE Corp. Email: xiao.min2@zte.com.cn Henrik Nydell Accedian Networks Email: hnydell@accedian.com Richard Foote Nokia Email: footer.foote@nokia.com Adi Masputra Apple Inc. One Apple Park Way Cupertino, CA 95014 USA Email: adi@apple.com Ernesto Ruffini OutSys via Caracciolo, 65 Milano 20155 Italy Email: eruffini@outsys.org Mirsky, et al. Expires May 3, 2020 [Page 20]