This document describes techniques for allowing sites running the
Locator/ID Separation Protocol (LISP) to interoperate with Internet
sites (which may be using either IPv4, IPv6, or both) but which are
not running LISP. A fundamental property of LISP speaking sites is
that they use Endpoint Identifiers (EIDs), rather than traditional IP
addresses, in the source and destination fields of all traffic they
emit or receive. While EIDs are syntactically identical to IPv4 or
IPv6 addresses, normally routes to them are not carried in the global
routing system so an interoperability mechanism is needed for non-
LISP-speaking sites to exchange traffic with LISP-speaking sites.
This document introduces three such mechanisms. The first uses a new
network element, the LISP Proxy Ingress Tunnel Routers (PITR)
(Section 5) to act as a intermediate LISP Ingress Tunnel Router (ITR)
for non-LISP-speaking hosts. Second the document adds Network
Address Translation (NAT) functionality to LISP Ingress and LISP
Egress Tunnel Routers (xTRs) to substitute routable IP addresses for
non-routable EIDs. Finally, this document introduces a Proxy Egress
Tunnel Router (PETR) to handle cases where a LISP ITR cannot send
packets to non-LISP sites without encapsulation.
Working Group Summary
The work group process for this document was uneventful.
This document is a descriptive tome for techniques in LISP
interoperation. It has had significant review as with all other LISP
The Document Shepherd is Terry Manderson and the responsible
Area Director is Jari Arkko.