Transparent Interconnection of Lots of Links (TRILL): MTU Negotiation
RFC 8249
Document | Type | RFC - Proposed Standard (September 2017; No errata) | |
---|---|---|---|
Authors | Mingui Zhang , Xudong Zhang , Donald Eastlake , Radia Perlman , Somnath Chatterjee | ||
Last updated | 2017-09-30 | ||
Replaces | draft-zhang-trill-mtu-negotiation | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Susan Hares | ||
Shepherd write-up | Show (last changed 2017-01-13) | ||
IESG | IESG state | RFC 8249 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Alia Atlas | ||
Send notices to | (None) | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) M. Zhang Request for Comments: 8249 X. Zhang Updates: 6325, 7177, 7780 D. Eastlake 3rd Category: Standards Track Huawei ISSN: 2070-1721 R. Perlman Dell EMC S. Chatterjee Cisco September 2017 Transparent Interconnection of Lots of Links (TRILL): MTU Negotiation Abstract The base IETF TRILL (Transparent Interconnection of Lots of Links) protocol has a TRILL campus-wide MTU feature, specified in RFCs 6325 and 7177, that assures that link-state changes can be successfully flooded throughout the campus while being able to take advantage of a campus-wide capability to support jumbo packets. This document specifies recommended updates to that MTU feature to take advantage, for appropriate link-local packets, of link-local MTUs that exceed the TRILL campus MTU. In addition, it specifies an efficient algorithm for local MTU testing. This document updates RFCs 6325, 7177, and 7780. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8249. Zhang, et al. Standards Track [Page 1] RFC 8249 MTU Negotiation September 2017 Copyright Notice Copyright (c) 2017 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 (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 ....................................................3 1.1. Conventions Used in This Document ..........................3 2. Link-Wide TRILL MTU Size ........................................4 2.1. Operations .................................................5 3. Testing Link MTU Size ...........................................6 4. Refreshing Sz ...................................................8 5. Relationship between Port MTU, Lz, and Sz .......................9 6. LSP Synchronization ............................................10 7. Recommendations for Traffic Link Testing of MTU Size ...........10 8. Backward Compatibility .........................................11 9. Security Considerations ........................................11 10. Additions to Configuration ....................................12 10.1. Per-RBridge Configuration ................................12 10.2. Per-RBridge Port Configuration ...........................12 11. IANA Considerations ...........................................12 12. References ....................................................12 12.1. Normative References .....................................12 12.2. Informative References ...................................14 Acknowledgements ..................................................14 Authors' Addresses ................................................14 Zhang, et al. Standards Track [Page 2] RFC 8249 MTU Negotiation September 2017 1. Introduction [RFC6325] describes the way RBridges agree on the campus-wide minimum acceptable inter-RBridge MTU (Maximum Transmission Unit) size (called "Sz") to ensure that link-state flooding operates properly and all RBridges converge to the same link state. For the proper operation of TRILL (Transparent Interconnection of Lots of Links) IS-IS, all RBridges format their Link State Protocol Data Units (LSPs) to fit in Sz. [RFC7177] diagrams the state transitions of an adjacency. If MTUShow full document text