--- 1/draft-ietf-lisp-rfc6830bis-34.txt 2020-09-09 06:13:58.220685875 -0700 +++ 2/draft-ietf-lisp-rfc6830bis-35.txt 2020-09-09 06:13:58.316688305 -0700 @@ -5,21 +5,21 @@ Intended status: Standards Track vaf.net Internet Consulting Expires: March 13, 2021 D. Meyer 1-4-5.net D. Lewis Cisco Systems A. Cabellos (Ed.) UPC/BarcelonaTech September 9, 2020 The Locator/ID Separation Protocol (LISP) - draft-ietf-lisp-rfc6830bis-34 + draft-ietf-lisp-rfc6830bis-35 Abstract This document describes the Data-Plane protocol for the Locator/ID Separation Protocol (LISP). LISP defines two namespaces, End-point Identifiers (EIDs) that identify end-hosts and Routing Locators (RLOCs) that identify network attachment points. With this, LISP effectively separates control from data, and allows routers to create overlay networks. LISP-capable routers exchange encapsulated packets according to EID-to-RLOC mappings stored in a local Map-Cache. @@ -988,22 +988,21 @@ to 0 if it has good reason to believe there are unresolvable path MTU issues between the sending ITR and the receiving ETR. This specification RECOMMENDS that L be defined as 1500. Additional information about in-network MTU and fragmentation issues can be found at [RFC4459]. 7.2. A Stateful Solution to MTU Handling An ITR stateful solution to handle MTU issues is described as - follows, this solution can only be used with IPv4-encapsulated - packets: + follows: 1. The ITR will keep state of the effective MTU for each Locator per Map-Cache entry. The effective MTU is what the core network can deliver along the path between the ITR and ETR. 2. When an IPv4-encapsulated packet with the DF bit set to 1, exceeds what the core network can deliver, one of the intermediate routers on the path will send an an ICMPv4 Unreachable/Fragmentation-Needed to the ITR, respectively. The ITR will parse the ICMP message to determine which Locator is