INTERNET-DRAFT Mingui Zhang Intended Status: Proposed Standard Huafeng Wen Expires: October 25, 2014 Huawei Jie Hu China Telecom April 23, 2014 STP Application of ICCP draft-ietf-pwe3-iccp-stp-01.txt Abstract Inter-Chassis Communication Protocol (ICCP) supports the inter- chassis redundancy mechanism which achieves high network availability. In this document, the PEs in a Redundant Group (RG) running ICCP are used to offer multi-homed connectivity to Spanning Tree Protocol (STP) networks. The ICCP TLVs for the STP application are defined, therefore PEs from the RG can make use of these TLVs to synchronize the state and configuration data of the STP network. 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 other groups may also distribute working documents as Internet-Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html Copyright and License Notice Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. Mingui Zhang Expires October 25, 2014 [Page 1] INTERNET-DRAFT STP Application of ICCP April 23, 2014 This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://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 . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Conventions used in this document . . . . . . . . . . . . . 3 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3 2. The Use Case Scenario . . . . . . . . . . . . . . . . . . . . . 3 2.1. STP as an Application of ICCP . . . . . . . . . . . . . . . 4 2.2. A Private Solution: The BPDU Tunneling Model . . . . . . . 4 3. Spanning Tree Protocol Application TLVs . . . . . . . . . . . . 6 3.1. STP Connect TLV . . . . . . . . . . . . . . . . . . . . . . 6 3.2. STP Disconnect TLV . . . . . . . . . . . . . . . . . . . . 7 3.2.1. STP Disconnect Cause TLV . . . . . . . . . . . . . . . 8 3.3. STP Config TLVs . . . . . . . . . . . . . . . . . . . . . . 8 3.3.1. STP System Config . . . . . . . . . . . . . . . . . . . 8 3.3.2. STP Topology Changed Instances . . . . . . . . . . . . 9 3.3.3. STP CIST Root Time . . . . . . . . . . . . . . . . . . 10 3.3.4. STP MSTI Root Time . . . . . . . . . . . . . . . . . . 11 3.3.5. STP Region Name . . . . . . . . . . . . . . . . . . . . 12 3.3.6. STP Revision Level . . . . . . . . . . . . . . . . . . 12 3.3.7. STP Instance Priority . . . . . . . . . . . . . . . . . 13 3.3.8. STP Configuration Digest . . . . . . . . . . . . . . . 14 3.4. STP Synchronization Request TLV . . . . . . . . . . . . . . 14 3.5. STP Synchronization Data TLV . . . . . . . . . . . . . . . 16 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 17 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 17 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . 18 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18 6.1. Normative References . . . . . . . . . . . . . . . . . . . 18 6.2. Informative References . . . . . . . . . . . . . . . . . . 18 Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19 Mingui Zhang Expires October 25, 2014 [Page 2] INTERNET-DRAFT STP Application of ICCP April 23, 2014 1. Introduction Inter-Chassis Communication Protocol (ICCP) specifies a multi-chassis redundant mechanism, which enables PEs located in multi-chassis to act as a single Redundant Group (RG). This document introduces Spanning Tree Protocol (STP) as a new application of ICCP. When a bridge network running STP is connected to an RG, the RG members pretend to be a single root bridge to participate the operations of the STP. STP relevant information need be exchanged and synchronized among the RG members. ICCP TLVs for the STP application are specified for this purpose. 1.1. Conventions used in this document 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 RFC 2119 [RFC2119]. 1.2. Terminology ICCP: Inter-Chassis Communication Protocol STP: Spanning Tree Protocol MSTP: Multiple Spanning Tree Protocol DSLAM: Digital Subscriber Line Access Multiplexer MST: Multiple Spanning Trees CIST: Common and Internal Spanning Tree MSTI: Multiple Spanning Tree Instance BPDU: Bridge Protocol Data Unit In this document, unless otherwise explicitly noted, when the term STP is used, it also covers MSTP. 2. The Use Case Scenario In customers' broadband networks, bridged DSLAMs are usually geographically dispersed. It is a common case these DSLAMs are connected to carriers' L2VPN network at multiple points for the sake of reliability. Requirements from customers for this use case are listed as follows. o These DSLAMs are running STP. o These DSLAMs are not geographically close to each other. Multiple DSLAMs are connected to the carrier network at different locations. o When one connection to the carrier network fails, customers wish a Mingui Zhang Expires October 25, 2014 [Page 3] INTERNET-DRAFT STP Application of ICCP April 23, 2014 connection in another location can continue to work after the re- convergence of the STP rather than compromising the whole STP network. The failure of the connection may be due to the failure of the PE, the AC or even the CE (a DSLAM) itself. o Customers want to balance the load among those connections, therefore all those connections need be active. In order to meet these requirements, the 'ICCP-STP' model is proposed in Section 2.1. It introduces STP as a new application of ICCP. A private implementation is depicted in Section 2.2 to serve as a contrast. Its issues are analyzed. 2.1. STP as an Application of ICCP +--------------+ +=============+ | | | | | | | | | +---+ | | +-----+ | | +---+CE1+<6>-------<5>+ PE1 | | | <1> +---+ | | +-----+ | | +-+-+ | | || | | |CE3| | | || ICCP | | +-+-+ | | || | | <2> +---+ | | +-----+ | | +---+CE2+<3>-------<4>+ PE2 | | | +---+ | | +-----+ | | | | | | Multi-homed | | | | STP Network | | | +--------------+ +=============+ Figure 2.1: A STP network is multi-homed to an RG running ICCP. Figure 2.1 shows an example topology of this model. With ICCP, the whole RG will be virtualized to be a single bridge. The RG pretends that the ports connected to the STP network (port <4>, <5>) are from the same bridge. All these ports emit configuration BPDU with the highest root priority to trigger the construction of the spanning tree. In this way, the STP will always break a loop within the multi- homed STP network. Each RG member has its BridgeIdentifier (the MAC address). The least significant one is elected as the BridgeIdentifier of the 'vitualized root bridge'. 2.2. A Private Solution: The BPDU Tunneling Model Mingui Zhang Expires October 25, 2014 [Page 4] INTERNET-DRAFT STP Application of ICCP April 23, 2014 +--------------+ +=============+ | | | | | | | | | +---+ | | +-----+ | | +---+CE1+<6>-------<5>+ PE1 | | | <1> +---+ | | +-----+ | | +-+-+ | | ||BPDU | | |CE3| | | ||tunnel| | +-+-+ | | || | | <2> +---+ | | +-----+ | | +---+CE2+<3>-------<4>+ PE2 | | | +---+ | | +-----+ | | | | | | Multi-homed | | | | STP Network | | | +--------------+ +=============+ Figure 2.2: The BPDU Tunneling Model Figure 2.2 shows an example network of the 'BPDU tunneling' model. Two PEs tunnel BPDUs of the STP network over a PW. The OAM designed in [RFC7023] can be adopted for the interworking between MPLS and Ethernet. In this model, the ports connected to the STP network at the PEs' side are non-bridge ports (e.g., port <4>, <5>). The tunnel between PE1 and PE2 is a transparent tunnel of BPDUs. For CE1 and CE2, they regard that there is a direct link between them. Issues of this model are listed as follows. o Assume port <1> was blocked according to the STP calculation. Now, suppose link CE3-CE2 fails, port <2> is blocked while port <1> is unblocked. Since the BPDUs is just tunneled, PE2 is unaware of this change. It may continue to send traffic to CE3 via CE2 where a black-hole happens. In order to handle this issue, PEs have to snoop the Topology Change (TC) message of the STP network so the tunnel is not "transparent" to BPDUs anymore. When the TC event is sensed, these PEs should withdraw MAC addresses of those instances affected by the TC event across the carrier's network. o When port <4> fails, CE1 is unaware. Suppose CE2 is the root bridge, port <6> has to wait for 3 STP HELLO Intervals (3*2s) and 2 Forwarding Delays (2*15s). The STP network takes at least 36 seconds to complete the convergence. The convergence process of the STP network is greatly slowed down. This actually changes the behavior of customers' STP networks. Mingui Zhang Expires October 25, 2014 [Page 5] INTERNET-DRAFT STP Application of ICCP April 23, 2014 In order to speed up the convergence, CE1 has to sense the state of the link between CE2 and PE2. The interworking PEs and CEs have to cope with various combinations of failures. There is no standard solution yet. o RFC 7023 is scoped to only single segment PWs [RFC6310][RFC 7023]. When the STP network is attached to more than two PEs, a full mesh PWs have to be set up. It's not clear yet what behaviors these PEs should have. Compared with this 'BPDU tunneling' model, the advantage point of the "ICCP-STP" model is that PEs "participate" in the STP calculation, therefore we need not design the complex interworking mechanism. 3. Spanning Tree Protocol Application TLVs This section specifies the ICCP TLVs for the STP application. As an AC Redundancy application of ICCP, operations specified in Section 9.2 of [ICCP] should be referred. 3.1. STP Connect TLV This TLV is included in the RG Connect message to signal the establishment of STP application connection. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0040 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Protocol Version |A| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Optional Sub-TLVs | ~ ~ | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0040 for "STP Connect TLV" - Length Mingui Zhang Expires October 25, 2014 [Page 6] INTERNET-DRAFT STP Application of ICCP April 23, 2014 Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Protocol Version The version of this particular protocol for the purposes of ICCP. This is set to 0x0001. - A bit Acknowledgement Bit. Set to 1 if the sender has received a STP Connect TLV from the recipient. Otherwise, set to 0. - Reserved Reserved for future use. - Optional Sub-TLVs There are no optional Sub-TLVs defined for this version of the protocol. 3.2. STP Disconnect TLV This TLV is used in an RG Disconnect Message to indicate that the connection for the STP application is to be terminated. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0041 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Optional Sub-TLVs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0041 for "STP Disconnect TLV" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. Mingui Zhang Expires October 25, 2014 [Page 7] INTERNET-DRAFT STP Application of ICCP April 23, 2014 - Optional Sub-TLVs The only optional Sub-TLV defined for this version of the protocol is the "STP Disconnect Cause" TLV defined next: 3.2.1. STP Disconnect Cause 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x004C | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Disconnect Cause String | ~ ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x004C for "STP Disconnect Cause TLV" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Disconnect Cause String Variable length string specifying the reason for the disconnect. Used for network management. 3.3. STP Config TLVs The STP Config TLVs are sent in the RG Application Data message. When a STP Config TLV is received by a peering RB member, it SHOULD synchronize the configuration information contained in the TLV. TLVs specified from section 3.3.1 through section 3.3.8 contains such kind of configuration information. 3.3.1. STP System Config This TLV announces the local node's STP System Parameters to the RG peers. Mingui Zhang Expires October 25, 2014 [Page 8] INTERNET-DRAFT STP Application of ICCP April 23, 2014 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0042 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ROID | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MAC Address | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0042 for "STP System Config" - Length Length of the MAC address, which is 6 octets. -ROID As defined in Section 6.1.3 of [ICCP]. - MAC Address The MAC address of the sender. This MAC address is set to the BridgeIdentifier of the sender, as defined in [802.1q] section 13.23.2. The the least significant unsigned BridgeIdentifier is used as the MAC address of the Virtual Root Bridge mentioned in Section 2.1. 3.3.2. STP Topology Changed Instances This TLV is used to report the Topology Changed Instances to other members in the RG. The receiver RG member SHOULD enforce the Topology Change to its port connected to the STP network, including the flush out of MAC addresses relevant to the instances listed in this TLV. Mingui Zhang Expires October 25, 2014 [Page 9] INTERNET-DRAFT STP Application of ICCP April 23, 2014 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0043 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | InstanceID List | ~ ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0043 for "STP Topology Changed Instances" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - InstanceID List The list of the instances whose topology is changed as indicated by the Topology Change Notification (TCN) Messages as specified in [802.1q] section 13.14. 3.3.3. STP CIST Root Time This TLV is used to report the Value of CIST Root Time to other members in the RG. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0044 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MaxAge | MessageAge | FwdDelay | HelloTime | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RemainingHops | +-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type Mingui Zhang Expires October 25, 2014 [Page 10] INTERNET-DRAFT STP Application of ICCP April 23, 2014 set to 0x0044 for "STP CIST Root Time" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - MaxAge The Maximum Age of this TLV. - MessageAge The actual age of this TLV. - FwdDelay The delay before the port enters the forwarding status. - HelloTime The interval between two continuous configuration BPDUs. - RemainingHops The remaining hops of this TLV 3.3.4. STP MSTI Root Time This TLV is used to report the Value of MSTI Root Time to other members in the RG. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0045 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | InstanceID | RemainingHops | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0045 for "STP MSTI Root Time" Mingui Zhang Expires October 25, 2014 [Page 11] INTERNET-DRAFT STP Application of ICCP April 23, 2014 - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - InstanceID The instance identification number of the MSTI. - remainingHops The remaining hops of this TLV 3.3.5. STP Region Name This TLV is used to report the Value of Region Name to other members in the RG. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0046 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Region Name | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0046 for "STP Region Name" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Region Name The Name of the MST Region. 3.3.6. STP Revision Level This TLV is used to report the Value of Revision Level to other members in the RG. Mingui Zhang Expires October 25, 2014 [Page 12] INTERNET-DRAFT STP Application of ICCP April 23, 2014 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0047 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Revision Level | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0047 for "STP Revision Level" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Revision Level The Revision Level as specified in [802.1q] section 3.21; 3.3.7. STP Instance Priority This TLV is used to report the Value of Instance Priority to other members in the RG. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0048 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Pri | InstanceID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0048 for "STP Instance Priority" - Length Mingui Zhang Expires October 25, 2014 [Page 13] INTERNET-DRAFT STP Application of ICCP April 23, 2014 Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Pri The Instance Priority - InstanceID The instance identification number of the MSTI. 3.3.8. STP Configuration Digest This TLV is used to report the Value of STP VLAN Instance Mapping to other members in the RG. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x0049 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Configuration Digest | ~ ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x0049 for "STP Configuration Digest" - Length Length of the STP Configuration Digest which is 16 octets. - Configuration Digest As specified in [802.1q] section 13.7. 3.4. STP Synchronization Request TLV The STP Synchronization Request TLV is used in the RG Application Data message. This TLV is used by a device to request from its peer to re-transmit configuration or operational state. The following information can be requested: Mingui Zhang Expires October 25, 2014 [Page 14] INTERNET-DRAFT STP Application of ICCP April 23, 2014 - system configuration and/or state - configuration and/or state for a specific port The format of the TLV is 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x004A | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Request Number |C|S| Request Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Number | Actor Key | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type set to 0x004A for "STP Synchronization Request TLV" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Request Number 2 octets. Unsigned integer uniquely identifying the request. Used to match the request with a response. The value of 0 is reserved for unsolicited synchronization, and MUST NOT be used in the STP Synchronization Request TLV. - C Bit Set to 1 if request is for configuration data. Otherwise, set to 0. - S Bit Set to 1 if request is for running state data. Otherwise, set to 0. - Request Type 14-bits specifying the request type, encoded as follows: Mingui Zhang Expires October 25, 2014 [Page 15] INTERNET-DRAFT STP Application of ICCP April 23, 2014 0x00 Request System Data 0x01 Request Port Data 0x3FFF Request All Data - Port Number 2 octets. When Request Type field is set to 'Request Port Data', this field encodes the STP Port Number for the requested port. When the value of this field is 0, it denotes that all ports, whose STP Key is specified in the "Actor Key" field, are being requested. - Actor Key 2 octets. STP Actor key for the corresponding port. When the value of this field is 0 (and the Port Number field is 0 as well), it denotes that information for all ports in the system is being requested. 3.5. STP Synchronization Data TLV The STP Synchronization Data TLV is used in the RG Application Data message. A pair of these TLVs is used by a device to delimit a set of TLVs that are being transmitted in response to an STP Synchronization Request TLV. The delimiting TLVs signal the start and end of the synchronization data, and associate the response with its corresponding request via the 'Request Number' field. The STP Synchronization Data TLVs are also used for unsolicited advertisements of complete STP configuration and operational state data. The 'Request Number' field MUST be set to 0 in this case. This TLV has the following format: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type=0x004B | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Request Number | Flags | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - U and F Bits Both are set to 0. - Type Mingui Zhang Expires October 25, 2014 [Page 16] INTERNET-DRAFT STP Application of ICCP April 23, 2014 set to 0x004B for "STP Synchronization Data TLV" - Length Length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields. - Request Number 2 octets. Unsigned integer identifying the Request Number from the "STP Synchronization Request TLV" which solicited this synchronization data response. - Flags 2 octets, response flags encoded as follows: 0x00 Synchronization Data Start 0x01 Synchronization Data End 4. Security Considerations As an application running on the channel provided by ICCP, security considerations of [ICCP] should be referred. 5. IANA Considerations The ICC RG parameter types used by the application TLVs defined in Section 3 of this document should be assigned. ICC RG parameter types are 14-bit values. Parameter Type values 1 through 0x003A are specified in [ICCP]. This document adds the specification of values 0x003B through 0x004C. Parameter Type values 0x004D through 0x1FFF are to be assigned by IANA, using the "Expert Review" policy defined in [RFC5226]. Suggested parameter type space value allocations for the STP application are specified below: Parameter Type Description -------------- --------------------------------- 0x003B-0x003F Reserved 0x0040 STP Connect TLV 0x0041 STP Disconnect TLV 0x0042 STP System Config TLV 0x0043 STP Topology Changed Instances TLV 0x0044 STP STP CIST Root Time TLV 0x0045 STP MSTI Root Time TLV 0x0046 STP Region Name TLV 0x0047 STP Revision Level TLV 0x0048 STP Instance Priority TLV Mingui Zhang Expires October 25, 2014 [Page 17] INTERNET-DRAFT STP Application of ICCP April 23, 2014 0x0049 STP Configuration Digest TLV 0x004A STP Synchronization Request TLV 0x004B STP Synchronization Data TLV 0x004C STP Disconnect Cause TLV Acknowledgements Authors would like to thank the comments and suggestions from Gregory Mirsky. 6. References 6.1. Normative References [ICCP] L. Martini, S. Salam, et al, "Inter-Chassis Communication Protocol for L2VPN PE Redundancy", draft-ietf-pwe3-iccp-16.txt, in RFC Ed Queue. [802.1q] "IEEE Standard for Local and Metropolitan Area Networks--- Virtual Bridged Local Area Networks.". IEEE Std 802.1 Q-2005, May 19, 2006. 6.2. Informative References [RFC7023] D. Mohan, Ed., N. Bitar, Ed., A. Sajassi, Ed., S. DeLord, P. Niger, R. Qiu., "MPLS and Ethernet Operations, Administration, and Maintenance (OAM) Interworking", RFC 7023, October 2013. [RFC6310] Aissaoui, M., Busschbach, P., Martini, L., Morrow, M., Nadeau, T., and Y(J). Stein, "Pseudowire (PW) Operations, Administration, and Maintenance (OAM) Message Mapping", RFC 6310, July 2011. Mingui Zhang Expires October 25, 2014 [Page 18] INTERNET-DRAFT STP Application of ICCP April 23, 2014 Author's Addresses Mingui Zhang Huawei EMail: zhangmingui@huawei.com Huafeng Wen Huawei EMail: wenhuafeng@huawei.com Jie Hu China Telecom EMail: hujie@ctbri.com.cn Mingui Zhang Expires October 25, 2014 [Page 19]