ILNP - Identifier-Locator Network Protocol

Overview

This is an ongoing research project that is revisiting the addressing model of the Internet Architecture. In place of an IP Address, a (topological) Locator and a (node) Identifier value form an Identifier-Locator Vector (ILV) that is used for addressing. The name, "Identifier Locator Network Protocol (ILNP)", refers to both the architectural concepts, and also the core implementation of those concepts using IPv6. The architectural concepts are independent of a particular network protocol, but IPv6 allows those concepts to be implemented and deployed on existing infrastructure.

To facilitate clean, incremental deployment and backwards compatibility, ILNP:

• Works as a superset of IPv6, using IANA-allocated codepoints for extensions to IPv6.
• Uses no proxies.
• Requires no tunnels or overlays.
• Does not require NAT or other address translation.
• Works with existing routing protocols.
• Does not require any new functionality in existing routers or swicthes.
• Can with work with existing applications that already use IPv6.

In RFC6115(I), the IRTF Routing Research Group (RRG) co-chairs recommended that ILNP be pursued within the IETF.

The particular approach to addressing used in ILNP allows harmonious integration of various different functions that were developed over different timescales and retro-fitted to IP, and so might not work well together today:

• Dynamic site and node multihoming without increasing entropy in the Default-Free Zone (DFZ) Routing Information Base (RIB).
• Native support for multipath transport protocols.
• Identity (node) privacy and location (topological) privacy.
• Native, scalable support for mobile nodes and mobile networks.
• Localised addressing (NAT-like networking) for managing site addressing, by decoupling location from identity.
• Packet-level IP security and privacy working natively with multihoming, mobility, and localised addressing.
• Support for traffic engineering (TE) capability through naming.
• For the future, a simpler, cleaner Networking API for distributed applications.

A good starting point to find out more is to read the (short) paper from JSAC (2010) (preprint) and then RFC6740 (2012).

Background

Thinking on ILNP started was driven by actual problems with the Internet Architecture (RFC4984(I)) at the time: many of those issues still remain today. For example, an operational issue that directed initial thinking at an early stage was the concern over the growing size of the Internet routing table, specifically the Routing Information Base (RIB) (RFC4098) of the Default-Free Zone (DFZ).

The practical work was influenced by Mike O'Dell's prior work on the GSE / 8+8 proposal for IPv6 (specfically the 8-byte/8-byte partition for addressing), and by work undertaken in the IRTF Namespace Research Group (NSRG). However, ILNP takes a different direction in various ways from those earlier proposals and discussions, and has an in-kernel code-base that works on today's Internet.

Internet RFC documents

The following Experimental status RFC documents were reviewed and discussed within the IRTF Routing Research Group (RRG). The authors are extremely grateful to the IRTF RRG particpants, the IRTF RRG Chair (Tony Li), the IRTF Chair (Lars Eggert) and the RFC Editor team for all their help. (Please see the RFCs, linked below, for other acknowledgements.)

RFC6740(E) Identifier-Locator Network Protocol (ILNP) Architectural Description (Nov 2012)
RFC6741(E) Identifier-Locator Network Protocol (ILNP) Engineering Considerations (Nov 2012)
RFC6742(E) DNS Resource Records for the Identifier-Locator Network Protocol (ILNP) (Nov 2012)
RFC6743(E) ICMP Locator Update Message for the Identifier-Locator Network Protocol for IPv6 (ILNPv6) (Nov 2012)
RFC6744(E) IPv6 Nonce Destination Option for the Identifier-Locator Network Protocol for IPv6 (ILNPv6) (Nov 2012)
RFC6745(E) ICMP Locator Update Message for the Identifier-Locator Network Protocol for IPv4 (ILNPv4) (Nov 2012)
RFC6746(E) IPv4 Options for the Identifier-Locator Network Protocol (ILNP) (Nov 2012)
RFC6747(E) Address Resolution Protocol (ARP) for the Identifier-Locator Network Protocol for IPv4 (ILNPv4) (Nov 2012)
RFC6748(E) Optional Advanced Deployment Scenarios for the Identifier-Locator Network Protocol (ILNP) (Nov 2012)

Talks

• Miscellaneous
  • End-system controlled, dynamic multihoming and multipath transport.
    NANOG96, San Francisco, USA, 01-04 Feb 2026.
  • Are we stuck with the current Internet Protocol (IP)? (And does it matter if we are?).
    University of Cambridge Computer Laboratory, Systems Research Group Seminar. 09 Jun 2022.
    
• Media
  • A demonstration of video-streaming on a mobile node, using the ilnp-public-1 codebase (11 December 2019).
  • History of Networking: ILNP, Rule 11 Tech (formerly "Network Collective" podcast). 30 January 2019.
    Expand the section "Control Planes (other than BGP)".
    audio
• Tutorials
  • IETF102, Montreal, Canada (21 June 2018), with thanks to Joel Halpern.
• Security, Privacy and Resilience
  • Dagstuhl Seminar 15151 (April 2015)
  • Fast, Secure Failover for IP (MILCOM 2014)
• Overview of ILNP ("IP Without IP addresses")
  • Italian Networking Workshop (January 2015)
  • Global Future Internet (GFI) Summit (November 2013)
  • IIT Mandi (March 2013)
  • JANET (July 2012)
• Reducing DNS caching: Running on Zero:
  • GI2011 (April 2011)
  • NANOG50 (October 2010)
  • IETF79 Name Based Sockets BoF session (November 2010)
• ILNP: a whirlwind tour:
  • NANOG50 (October 2010)
  • T-Labs, Berlin (November 2010)
• Enabling mobile systems with ILNP, Ericsson Research Labs, San Jose, 18 August 2010.
• Developing ILNP, Keynote Talk at FIRE workshop, Identifying Enabling Technologies for Future Internet Experimentation, Chania, Crete, 16 July 2010.
• Evolving The Internet Architecture Through Naming:
  • NEC Labs Europe (Mar 2010);
  • Queen Mary University of London (Apr 2010);
  • University of Sao Paulo (May 2010);
  • University of California Davis (May 2010);
  • Swinburne University (November 2010).
• Reducing DNS caching or "How low can we go?", Networkshop38, Manchester, UK, 31 March 2010.
• Handle with Care: Naming, Layering and Caching "Broken" on the Internet, Seminar at University of St Andrews, 20 October 2009.
• DNS Caching: Running on Zero, MSN2009 - Multi-Service Networks Workshop 2009, Cosener's House, RAL, UK. 09 July 2009.
• What's in a name?, Seminar at BBN Technologies, Cambridge, Massachusetts, USA. 21 November 2008.
• Thoughts on a New Namespace (Overview of ILNP), Presentation to the IRTF Routing Research Group, Dublin, Ireland. July 2008.
• Naming for Networking, Seminar at ICU, Daejeon, Chungghongdo. Republic of Korea. 18 June 2008.

Datasets

• G. T. Haywood, S. N. Bhatti. Ephemeral Node Identifiers for Enhanced Flow Privacy (dataset). April 2025.
• R. Yanagida, S. N. Bhatti. Mobility Multihoming Duality (dataset). October 2024.
• G. T. Haywood, S. N. Bhatti. Defence against side-channel attacks for encrypted network communication using multiple paths (dataset). May 2024.
• G. T. Haywood, S. N. Bhatti, R. Yanagida. ILNP - Identifier-Locator Network Protocol : FreeBSD 14.0 @ IETF118/Prague (dataset). January 2024.
• S. N. Bhatti. dns-2009-q4-count : data files for paper, "Reducing DNS Caching". December 2022.

Papers

• G. T. Haywood, S. N. Bhatti, Ephemeral Node Identifiers for Enhanced Flow Privacy. Future Internet, vol. 17, no. 5, pages 1-27. April 2025. Dataset is here.
• R. Yanagida, S. N. Bhatti, Mobility-Multihoming Duality. Future Internet, vol. 16, no. 10, pages 1-42. October 2024. Dataset is here.
• G. T. Haywood, S. N. Bhatti, Defence against side-channel attacks for encrypted network communication using multiple paths. Cryptography, vol. 8, no. 2, pages 1-26. May 2024. Dataset is here.
• S. N. Bhatti, G. Haywood, R. Yanagida End-to-End Privacy for Identity & Location with IP. NIPAA21 - 2nd Workshop on New Internetworking Protocols, Architecture and Algorithms (ICNP 2021 - 29th IEEE International Conference on Network Protocols). Virtual event (COVID-19). Nov 2021.
• R. Yanagida, S. N. Bhatti. Seamless Internet connectivity for ubiquitous communication. PURBA2019, Pervasive Urban Applications Workshop (UBICOMP 2019). London, UK. Sep 2019.
• D. Phoomikiattisak, S. N. Bhatti. End-To-End Mobility for the Internet Using ILNP, Wireless Communications and Mobile Computing (WCMC), vol. 2019, Article ID 7464179, pages 29. Apr 2019.
• R. Yanagida, S. N. Bhatti. End-to-end networking with ILNP in Linux. netdev0x13 Technical Conference on Linux Networking, Prague, Czech Republic. Mar 2019.
• S. N. Bhatti, D. Phoomikiattisak, B. Simpson. IP without IP addresses. AINTEC 2016 - 12th Asian Internet Engineering Conf.. Bangkok, Thailand. Nov/Dec 2016.
• D. Phoomikiattisak, S. N. Bhatti. Control Plane Handoff Analysis for IP Mobility. WMNC 2016 - 9th IFIP Wireless and Mobile Networking Conf. Colmar, France. Jul 2016.
• D. Phoomikiatissak, S. N. Bhatti. Mobility as a First Class Function. WiMob 2015 - 11th IEEE Intl. Conf. Wireless and Mobile Computing, Networking and Communications. Abu Dhabi, UAE. Oct 2015.
• S. N. Bhatti, D. Phoomikiatissak, R. J. Atkinson. Fast, Secure Failover for IP. MILCOM 2014 - 33rd IEEE Military Communications Conf.. Baltimore, MD, USA. Oct 2014.
• D. Phoomikiatissak, S. N. Bhatti. IP-Layer Soft Handoff Implementation in ILNP. MobiArch 2014 - ACM Wkshp. Mobility in the Evolving Internet Architecture. Hawaii, USA. Sep 2014.
• B. Simpson, S. N. Bhatti. An identifier-locator approach to host multihoming. AINA 2014 - IEEE 28th Intl. Conf. Advanced Information Networking and Applications. Victoria, Canada. May 2014.
• D. Phoomikiattisak, S. N. Bhatti, Network Layer Soft Handoff for IP Mobility. PM2HW2N 2013 - 8th ACM Intl. Wkshp. Performance Monitoring, Measurement and Evaluation of Heterogeneous Wireless and Wired Networks. Barcelona, Spain. 03 Nov 2013.
• S. N. Bhatti, R. Atkinson, Secure & Agile Wide-Area Virtual Machine Mobility, 31st IEEE Military Communications Conference (MILCOM2012), Orlando, FL, USA 29 Oct - 01 Nov 2012 (cancelled due to Hurricane Sandy).
• S. N. Bhatti, R. Atkinson, J. Klemets, Integrating Challenged Networks, 30th IEEE Military Communcations Conference (MILCOM2011), Baltimore, USA 09-12 Nov 2011.
• S. Bhatti, R. Atkinson, Reducing DNS Caching, 14th IEEE Global Internet Symposium (GI2011), Shanghai, China. 15 April 2011.
• R. Atkinson, S. Bhatti, S. Hailes, Evolving the Internet Architecture Through Naming, IEEE Journal on Selected Areas in Communication (JSAC), vol. 28, no. 8, pp1319-1325, [IEEE] Oct 2010.
• D. Rehunathan, S. Bhatti A Comparative Assessment of Routing for Mobile Networks, 6th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob2010), Niagara Falls, Canada, 11-13 October 2010.
• R. Atkinson, S. Bhatti, S. Hailes, ILNP: Mobility, Multi-Homing, Localised Addressing and Security Through Naming, Telecommunication Systems, vol. 42, no. 3-4 pp273-291. [Springer] Dec 2009. ISSN 1018-4864 print / 1572-9451 online.
• R. Atkinson, S. Bhatti, Site-Controlled Secure Multi-homing and Traffic Engineering for IP, 28th IEEE Military Communications Conference (MILCOM), Boston, MA, USA, October 2009
• D. Rehunthan, R. Atkinson, S. Bhatti, Enabling Mobile Networks Through Secure Naming, 28th IEEE Military Communications Conference (MILCOM), Boston, MA, USA, October 2009
• R. Atkinson, S. Bhatti, and S. Hailes, Harmonised Resilience, Multi-homing and Mobility Capability for IP, 27th IEEE Military Communications Conference (MILCOM), San Diego, CA, USA, November 2008.
• R. Atkinson, S. Bhatti, and S. Hailes, Mobility Through Naming: Impact on DNS, 3rd ACM International Workshop on Mobility in the Evolving Internet (MobiArch), Seatlle, USA, August 2008.
• R. Atkinson, S. Bhatti, and S. Hailes, A Proposal for Unifying Mobility with Multi-Homing, NAT, and Security, 5th ACM International Workshop on Mobility Management and Wireless Access (MobiWAC), Chania, Crete, October 2007.
• R. Atkinson, S. Bhatti, and S. Hailes, Mobility as an Integrated Service through the Use of Naming, 2nd ACM International Workshop on Mobility in the Evolving Internet (MobiArch), Kyoto, Japan, August 2007.
• R. Atkinson, M. Lad, S. Bhatti, and S. Hailes, A Proposal for Coalition Networking in Dynamic Operational Environments, 25th IEEE Military Communications Conference (MILCOM), Washington, DC, USA, November 2006.
• R. Atkinson, S. Bhatti, An Introduction to the Identifier-Locator Network Protocol (ILNP), IEEE London Communications Symposium (LCS), September 2006.
• R. Atkinson, S. Bhatti, Naming Enhancements for the Internet, IEEE London Communications Symposium (LCS), September 2004.

Contact

Saleem Bhatti