Technical Summary
This document describes a simple distributed index system to be used
by a Locator/ID Separation Protocol (LISP) Ingress Tunnel Router
(ITR) or Map Resolver (MR) to find the Egress Tunnel Router (ETR)
which holds the mapping information for a particular Endpoint
Identifier (EID). The MR can then query that ETR to obtain the
actual mapping information, which consists of a list of Routing
Locators (RLOCs) for the EID. Termed the Alternative Logical
Topology (ALT), the index is built as an overlay network on the
public Internet using the Border Gateway Protocol (BGP) and the
Generic Routing Encapsulation (GRE). Using these proven protocols,
the ALT can be built and deployed relatively quickly without any
changes to the existing routing infrastructure.
Working Group Summary
Many of the comments received during last call were complex and
difficult for the working group to understand. The working group last
call was held open for an extended time to ensure sufficient discussion
and sufficient effort to address those objections.
Document Quality
Several (3+) LISP implementations exist using the ALT topology.
Personnel
Terry Manderson is the Document Shepherd, and Jari Arkko is the
responsible Area Director.