Cisco Locator/ID Separation Protocol (LISP) is routing architecture that provides new semantics for IP addressing. The current IP routing and addressing architecture uses a single numbering space, the IP address, to express two pieces of information:
- Device identity
- The way the device attaches to the network
The LISP routing architecture design separates the device identity, or endpoint identifier (EID), from its location, or routing locator (RLOC), into two different numbering spaces. Splitting EID and RLOC functions yields several advantages.
Check out this video for a quick review of LISP.
Although LISP was designed to deal with the route scalability problem in the Internet, it turns out is has the capability to help with the transition to IP Version 6 (IPv6), the next-generation Internet protocol.
The transition to IPv6 is an immediate challenge facing Public Sector, and specifically Federal customers today due to Government mandates and impending IPv4 address exhaustion for consumers of Government services.
Because IPv6 is not backward compatible with IPv4, and because its deployment and operation are different from that of IPv4, development and implementation of an IPv6 transition strategy is imperative. Many techniques exist to ease the transition to IPv6, and the network-based IPv6 transition techniques can be divided generally into three categories: dual-stack IPv4 and IPv6, IPv6 tunneling, and IPv6 translation.
Each approach has its features, benefits, and limitations; they are not all equivalent in terms of cost, complexity, or capabilities. Most likely, a combination of these techniques will provide the best solution. The role that the Locator/ID Separation Protocol (LISP) being developed by Cisco and the IETF can play in IPv6 transition strategies is documented in this Whitepaper.
Incorporating LISP into an IPv6 transition strategy can simplify the initial rollout of IPv6 by taking advantage of the LISP mechanisms to encapsulate IPv6 host packets within IPv4 headers (or IPv4 host packets within IPv6 headers). For example, you can build IPv6 islands and connect them with existing IPv4 Internet connectivity.
LISP is a Cisco innovation that is being promoted as an open standard. Cisco participates in standards bodies such as the IETF LISP Working Group to develop the LISP architecture.
For further information, check the Cisco site on LISP.