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Internet Area Working Group                                     J. Thain
Internet-Draft                                               One Limited
Intended status: Standards Track                           17 April 2026
Expires: 19 October 2026


                   Internet Protocol Version 8 (IPv8)
                          draft-thain-ipv8-02

Abstract

   Internet Protocol Version 8 (IPv8) is a managed network protocol
   suite that transforms how networks of every scale -- from home
   networks to the global internet -- are operated, secured, and
   monitored.  Every manageable element in an IPv8 network is authorised
   via OAuth2 JWT tokens served from a local cache.  Every service a
   device requires is delivered in a single DHCP8 lease response.  Every
   packet transiting to the internet is validated at egress against a
   DNS8 lookup and a WHOIS8 registered active route.  Network telemetry,
   authentication, name resolution, time synchronisation, access
   control, and translation are unified into a single coherent Zone
   Server platform.

   IPv4 is a proper subset of IPv8.  An IPv8 address with the routing
   prefix field set to zero is an IPv4 address.  No existing device,
   application, or network requires modification.  The suite is 100%
   backward compatible.  There is no flag day and no forced migration at
   any layer.

   IPv8 also resolves IPv4 address exhaustion.  Each Autonomous System
   Number (ASN) holder receives 4,294,967,296 host addresses.  The
   global BGP8 routing table is structurally bounded by ASN count rather
   than prefix count.  WHOIS8 is a critical infrastructure service
   underpinning this model.

   This document is one of the companion specifications:

   *  draft-thain-ipv8-02 Core protocol (this document)
   *  draft-thain-routing-protocols-00 BGP8, IBGP8, OSPF8, IS-IS8, CF
   *  draft-thain-rine-00 Regional Inter-Network Exchange
   *  draft-thain-zoneserver-00 Zone Server Architecture
   *  draft-thain-whois8-00 WHOIS8 Protocol
   *  draft-thain-netlog8-00 NetLog8 Protocol
   *  draft-thain-support8-00 ARP8, ICMPv8, Route8
   *  draft-thain-ipv8-mib-00 IPv8 MIB and SNMPv8
   *  draft-thain-wifi8-00 WiFi8 Protocol
   *  draft-thain-update8-00 Update8 and NIC Certification




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Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 19 October 2026.

Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
     1.2.  The Network Management Problem  . . . . . . . . . . . . .   4
     1.3.  The IPv8 Management Philosophy  . . . . . . . . . . . . .   5
     1.4.  Zone Server Redundancy and Even/Odd Addressing  . . . . .   6
     1.5.  East-West and North-South Security  . . . . . . . . . . .   6
     1.6.  Address Exhaustion  . . . . . . . . . . . . . . . . . . .   7
     1.7.  Routing Protocol Improvements . . . . . . . . . . . . . .   8
     1.8.  Backward Compatibility and Transition . . . . . . . . . .   9
   2.  ARP8-Driven Version Selection . . . . . . . . . . . . . . . .   9
     2.1.  The Foundational Rule . . . . . . . . . . . . . . . . . .   9
     2.2.  Neighbor Capability Discovery . . . . . . . . . . . . . .   9
     2.3.  Version Selection at Transmit Time  . . . . . . . . . . .  10
     2.4.  Router Forwarding . . . . . . . . . . . . . . . . . . . .  10
     2.5.  Attribution at IPv4 Hops  . . . . . . . . . . . . . . . .  11



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     2.6.  Transition Properties . . . . . . . . . . . . . . . . . .  11
   3.  Motivation and Problem Statement  . . . . . . . . . . . . . .  11
     3.1.  Management Fragmentation  . . . . . . . . . . . . . . . .  11
     3.2.  Address Exhaustion  . . . . . . . . . . . . . . . . . . .  12
     3.3.  Routing Table Growth  . . . . . . . . . . . . . . . . . .  12
     3.4.  Requirements for a Viable Successor . . . . . . . . . . .  13
   4.  IPv8 Address Format . . . . . . . . . . . . . . . . . . . . .  13
     4.1.  Structure . . . . . . . . . . . . . . . . . . . . . . . .  13
     4.2.  Address Space . . . . . . . . . . . . . . . . . . . . . .  13
     4.3.  IPv4 Representation in IPv8 . . . . . . . . . . . . . . .  13
     4.4.  ASN Encoding in r.r.r.r . . . . . . . . . . . . . . . . .  14
     4.5.  Internal Zone Prefix (127.0.0.0/8)  . . . . . . . . . . .  14
     4.6.  Inter-Company Interop Prefix (127.127.0.0)  . . . . . . .  15
     4.7.  Two-XLATE8 Interop Model  . . . . . . . . . . . . . . . .  15
     4.8.  Private Interop ASN (ASN 65534) . . . . . . . . . . . . .  15
     4.9.  RINE Peering Prefix (100.0.0.0/8) . . . . . . . . . . . .  15
     4.10. Interior Link Convention (222.0.0.0/8)  . . . . . . . . .  16
     4.11. Address Usage Model . . . . . . . . . . . . . . . . . . .  16
   5.  Address Classes . . . . . . . . . . . . . . . . . . . . . . .  16
     5.1.  Anycast . . . . . . . . . . . . . . . . . . . . . . . . .  18
   6.  IPv8 Packet Header  . . . . . . . . . . . . . . . . . . . . .  18
     6.1.  Header Format . . . . . . . . . . . . . . . . . . . . . .  18
     6.2.  Socket API Compatibility  . . . . . . . . . . . . . . . .  19
   7.  ASN Dot Notation  . . . . . . . . . . . . . . . . . . . . . .  19
   8.  DNS A8 Record Type  . . . . . . . . . . . . . . . . . . . . .  20
   9.  Routing Protocol Behaviour  . . . . . . . . . . . . . . . . .  20
     9.1.  Mandatory Routing Protocols . . . . . . . . . . . . . . .  20
     9.2.  Deprecated Routing Protocols  . . . . . . . . . . . . . .  21
     9.3.  eBGP8 - Mandatory Exterior Gateway Protocol . . . . . . .  21
     9.4.  IBGP8 - Inter-Zone Routing  . . . . . . . . . . . . . . .  21
     9.5.  OSPF8 - Intra-Zone Routing  . . . . . . . . . . . . . . .  21
     9.6.  IS-IS8 - Optional Interior Gateway Protocol . . . . . . .  21
     9.7.  Two-Tier Routing Table  . . . . . . . . . . . . . . . . .  22
     9.8.  VRF - Virtual Routing and Forwarding  . . . . . . . . . .  22
   10. ICMPv8  . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
   11. Multicast . . . . . . . . . . . . . . . . . . . . . . . . . .  22
     11.1.  Intra-ASN Multicast  . . . . . . . . . . . . . . . . . .  22
     11.2.  Cross-ASN Multicast  . . . . . . . . . . . . . . . . . .  22
     11.3.  Cross-ASN Multicast Group Assignments  . . . . . . . . .  23
   12. Anycast . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
   13. Broadcast . . . . . . . . . . . . . . . . . . . . . . . . . .  23
   14. Compatibility and Transition  . . . . . . . . . . . . . . . .  23
     14.1.  Single Stack Operation . . . . . . . . . . . . . . . . .  23
     14.2.  IPv4 Network Compatibility . . . . . . . . . . . . . . .  23
     14.3.  8to4 - IPv8 Across IPv4-Only Networks  . . . . . . . . .  24
     14.4.  Transition Sequence  . . . . . . . . . . . . . . . . . .  24
   15. CGNAT Behaviour . . . . . . . . . . . . . . . . . . . . . . .  24
     15.1.  XLATE8 Even/Odd Load Balancing . . . . . . . . . . . . .  25



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   16. Application Compatibility . . . . . . . . . . . . . . . . . .  25
   17. Cloud Provider Applicability  . . . . . . . . . . . . . . . .  25
   18. Device Compliance Tiers . . . . . . . . . . . . . . . . . . .  25
     18.1.  Tier 1 - End Device  . . . . . . . . . . . . . . . . . .  25
     18.2.  Tier 2 - L2 Network Device . . . . . . . . . . . . . . .  26
     18.3.  Tier 3 - L3 Network Device . . . . . . . . . . . . . . .  26
     18.4.  Spanning Tree - PVRST Mandatory  . . . . . . . . . . . .  26
     18.5.  NIC Broadcast Rate Limits  . . . . . . . . . . . . . . .  26
   19. Security Considerations . . . . . . . . . . . . . . . . . . .  26
     19.1.  ASN Prefix Spoofing  . . . . . . . . . . . . . . . . . .  26
     19.2.  Internal Zone Prefix Protection  . . . . . . . . . . . .  27
     19.3.  RINE Prefix Protection . . . . . . . . . . . . . . . . .  27
     19.4.  Interior Link Convention Protection  . . . . . . . . . .  27
     19.5.  RFC 1918 Address Privacy . . . . . . . . . . . . . . . .  27
     19.6.  Cross-ASN Multicast Filtering  . . . . . . . . . . . . .  27
     19.7.  /16 Minimum Prefix Enforcement . . . . . . . . . . . . .  27
   20. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  27
     20.1.  IP Version Number  . . . . . . . . . . . . . . . . . . .  27
     20.2.  Internal Zone Prefix Reservation . . . . . . . . . . . .  27
     20.3.  RINE Prefix Reservation  . . . . . . . . . . . . . . . .  28
     20.4.  Interior Link Convention . . . . . . . . . . . . . . . .  28
     20.5.  Cross-ASN Multicast Range  . . . . . . . . . . . . . . .  28
     20.6.  Broadcast Reservation  . . . . . . . . . . . . . . . . .  28
     20.7.  DNS A8 Record Type . . . . . . . . . . . . . . . . . . .  28
     20.8.  Multicast Group Assignments  . . . . . . . . . . . . . .  28
     20.9.  Private ASN Reservations . . . . . . . . . . . . . . . .  28
   21. Informative References  . . . . . . . . . . . . . . . . . . .  28
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  30

1.  Introduction

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

1.2.  The Network Management Problem

   Modern network management is characterised by fragmentation.  DHCP,
   DNS, NTP, logging, monitoring, and authentication are separate
   products, separately licensed, separately configured, and separately
   maintained with no shared awareness of network state.  A device
   connecting to a network may require manual configuration of a dozen
   independent services before it is operational.  Security is
   inconsistent -- some services are authenticated, others are not.



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   Failures require correlating data across systems that were never
   designed to work together.

   This fragmentation scales with every device added.  Small networks
   cannot afford the operational complexity.  Large networks cannot
   afford the inconsistency.  The global internet has no coherent
   mechanism to validate that advertised routes are legitimately held by
   their advertisers, or that packets transiting to external
   destinations have been validated against any registry of active
   routes.

   IPv6 [RFC8200] addressed address exhaustion but did not address
   management fragmentation.  After 25 years of deployment effort IPv6
   carries a minority of global internet traffic.  The operational cost
   of the dual-stack transition model, combined with the absence of
   management improvement, proved commercially unacceptable.

   IPv8 addresses both problems simultaneously.

1.3.  The IPv8 Management Philosophy

   The central operational concept in IPv8 is the Zone Server -- a
   paired active/active platform that runs every service a network
   segment requires: address assignment (DHCP8), name resolution (DNS8),
   time synchronisation (NTP8), telemetry collection (NetLog8),
   authentication caching (OAuth8), route validation (WHOIS8 resolver),
   access control enforcement (ACL8), and IPv4/IPv8 translation
   (XLATE8).

   A device connecting to an IPv8 network sends one DHCP8 Discover and
   receives one response containing every service endpoint it requires.
   No subsequent manual configuration is needed for any service.  The
   device is fully operational -- authenticated, logged, time-
   synchronised, zone-policy-enforced -- before its first user
   interaction.

   Every manageable element in an IPv8 network is authorised via OAuth2
   JWT tokens [RFC7519].  Tokens are validated locally by the OAuth8
   cache on the Zone Server without round trips to external identity
   providers.  A device in a remote location with a temporarily
   unreachable cloud identity provider continues to authenticate
   normally -- the OAuth8 cache holds all public keys and validates
   signatures locally in sub- millisecond time.  JWT tokens may be
   served by a local OAuth2 authority (home router operating in local
   authority mode) or by a cached enterprise OAuth2 provider.
   Authentication is universal, consistent, and requires no per-service
   credential management.




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   Firmware and software updates for L1-L4 stack components are managed
   via the Update8 protocol [UPDATE8].  Update8 defines a standard
   vendor feed format, Zone Server validated proxy, optional local
   caching, device criticality-based scheduling, and rollback prevention
   enforced in NIC hardware.  Devices receive updates only from DNS-
   named sources validated by the Zone Server.  Connection to an update
   source identified by IP address is blocked by default.

   The 127.0.0.0/8 r.r.r.r range is permanently reserved as the IPv8
   internal zone prefix space.  Organisations assign internal zone
   prefixes (127.1.0.0, 127.2.0.0 etc) to network zones and regions.
   Internal zone addresses are never routed externally.  No address
   conflict between zones is possible.  An organisation may build a
   network of arbitrary geographic and organisational scale -- with
   dozens of regional zones, each containing thousands of devices --
   using familiar routing protocols without any external address
   coordination.

1.4.  Zone Server Redundancy and Even/Odd Addressing

   Every IPv8 network segment operates with two Zone Servers, assigned
   the two highest addresses in the subnet: .254 (even) and .253 (odd).
   These are the two default gateways issued to every device in the
   DHCP8 lease response.

   IPv8 traffic follows an even/odd affinity model: even-addressed hosts
   route via the even Zone Server (.254) and odd-addressed hosts route
   via the odd Zone Server (.253).  Each Zone Server is the PVRST root
   for its respective VLANs.  Under normal operation the load is
   distributed across both Zone Servers with no single point of failure.
   On Zone Server failure, traffic fails over to the surviving gateway
   automatically.

   Hosts SHOULD be assigned addresses matching their primary traffic
   path.  Dual-NIC hosts SHOULD be issued one even and one odd address
   by DHCP8 -- one per NIC -- enabling full simultaneous use of both
   gateway paths and both physical links.  Full redundancy is achieved
   with no additional configuration: loss of either NIC or either Zone
   Server results in automatic failover on the surviving path.
   Administrators MAY deviate from even/odd assignment where operational
   requirements justify it.

1.5.  East-West and North-South Security

   IPv8 addresses two distinct traffic security problems:






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   *East-west security* -- traffic between devices within a network --
   is enforced by ACL8 zone isolation.  Devices communicate only with
   their designated service gateway.  The service gateway communicates
   only with the designated cloud service.  Lateral movement between
   devices or zones is architecturally prevented by the absence of any
   permitted route to any other destination.  Three independent
   enforcement layers provide defence in depth: NIC firmware ACL8, Zone
   Server gateway ACL8, and switch port OAuth2 hardware VLAN
   enforcement.

   *North-south security* -- traffic from internal devices to the
   internet -- is enforced at the Zone Server egress by two mandatory
   validation steps.  First, every outbound connection must have a
   corresponding DNS8 lookup -- no DNS lookup means no XLATE8 state
   table entry means the connection is blocked.  Second, the destination
   ASN is validated against the WHOIS8 registry -- if the destination
   prefix is not registered as an active route by a legitimately
   registered ASN holder the packet is dropped.  These two steps
   together eliminate the primary malware command-and-control channel:
   connection to hardcoded IP addresses without DNS resolution.

   At the global routing level, BGP8 route advertisements are validated
   against WHOIS8 before installation in the routing table.  A route
   that cannot be validated is not installed.  Manual bogon filter list
   maintenance is eliminated.  Prefix hijacking is architecturally
   difficult -- an attacker must compromise both an RIR registry entry
   and produce a validly signed WHOIS8 record.

1.6.  Address Exhaustion

   IANA completed allocation of the IPv4 unicast address space in
   February 2011.  CGNAT has extended IPv4 life but introduces latency,
   breaks peer-to-peer protocols, and complicates troubleshooting.  The
   address exhaustion problem is architectural and cannot be resolved
   within the 32-bit IPv4 address space.

   IPv8 resolves address exhaustion as a consequence of its addressing
   architecture, not as a primary design goal.  The 64-bit IPv8 address
   space provides 2^64 unique addresses.  Each ASN holder receives 2^32
   host addresses -- 4,294,967,296 addresses -- sufficient for any
   organisation at any scale without address exhaustion, CGNAT, or
   renumbering.









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   IPv4 is a proper subset of IPv8.  An IPv8 address with r.r.r.r =
   0.0.0.0 is an IPv4 address, processed by standard IPv4 rules.  No
   existing device, application, or network requires modification to
   participate in an IPv8 network.  The suite is 100% backward
   compatible.  There is no flag day and no forced migration at any
   layer.

   The global BGP8 routing table is structurally bounded by ASN count.
   The /16 minimum injectable prefix rule prevents deaggregation -- an
   ASN may advertise multiple /16 prefixes but never more specific.
   Route acceptance is validated against WHOIS8, which serves as a
   critical infrastructure service for the global routing system.  The
   BGP4 routing table exceeded 900,000 prefixes with no architectural
   bound.  The BGP8 routing table is bounded by the number of /16
   prefixes held across all ASNs -- a structurally finite and manageable
   set.

1.7.  Routing Protocol Improvements

   IPv8 extends OSPF8 [RFC2328], BGP8 [RFC4271] (both iBGP8 and eBGP8),
   and IS-IS8 with a unified path quality metric -- the Cost Factor
   (CF).

   CF is a 32-bit accumulated metric derived from seven components
   measured from TCP session telemetry: round trip time, packet loss,
   congestion window state, session stability, link capacity, economic
   policy, and geographic distance as a physics floor.  CF accumulates
   across every BGP8 hop from source to destination.  Every router
   independently selects the path with the lowest accumulated CF without
   coordination.

   CF combines the dynamic composite path quality of EIGRP, the
   accumulated cost model of OSPF, and proportional load balancing
   across multiple paths -- in a single open versioned algorithm that
   operates end-to-end across AS boundaries.  OSPF and EIGRP stop at the
   AS boundary.  CF does not.

   The geographic component of CF sets a physics floor -- no path can
   appear better than the speed of light over the great circle distance
   allows.  A path that measures faster than physics permits is flagged
   immediately as a CF anomaly.

   CF is an open versioned algorithm.  CFv1 is the mandatory baseline.
   Future versions may add carbon cost, jitter, time of day, and
   application layer latency signals through the IETF process.






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   CF contribution for an IPv4-only hop is zero -- neither a positive
   nor a negative weight -- unless an operator explicitly assigns a CF
   policy weight to that hop.  IPv4 hops are invisible to CF path
   optimisation by default.  This ensures IPv4 transit paths are neither
   preferred nor penalised in CF path selection solely by virtue of
   their protocol version.

1.8.  Backward Compatibility and Transition

   IPv4 is a proper subset of IPv8:

   IPv8 address with r.r.r.r = 0.0.0.0 = IPv4 address
   Processed by standard IPv4 rules
   No modification to IPv4 device required
   No modification to IPv4 application required
   No modification to IPv4 internal network required

   IPv8 does not require dual-stack operation.  There is no flag day.
   8to4 tunnelling enables IPv8 islands separated by IPv4- only transit
   networks to communicate immediately.  CF naturally incentivises IPv4
   transit ASNs to upgrade by measuring higher latency on 8to4 paths --
   an automatic economic signal without any mandate.

   Transition phases are independent.  Tier 1 ISPs, cloud providers,
   enterprises, and consumer ISPs may adopt IPv8 in any order and at any
   pace. 8to4 ensures interoperability throughout.

2.  ARP8-Driven Version Selection

2.1.  The Foundational Rule

   An IPv8 host or router transmitting to a neighbor on a shared segment
   MUST use the IP protocol version matching that neighbor's capability
   as recorded in the ARP8 cache.  Capability is discovered at first
   contact via ARP8 dual probe and recorded permanently for the lifetime
   of the cache entry.

2.2.  Neighbor Capability Discovery

   On first contact with a neighbor, an IPv8 host issues two probes in
   parallel:

   t=0ms    ARP8 probe  (IPv8 capable neighbor expected)
   t=50ms   ARP4 probe  (IPv4 fallback if no ARP8 response)

   The first response received determines the neighbor's recorded
   capability.  Once recorded, the capability entry persists for the
   lifetime of the ARP8 cache entry.  No per-packet probing is required.



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2.3.  Version Selection at Transmit Time

   The key rule of IPv8 backward compatibility: an IPv8 device SHALL
   transmit only IPv4 packets to IPv4 devices.  There are no exceptions.
   An IPv4 device on any segment with IPv8 devices will never receive a
   packet it cannot process.

   For a neighbor recorded as IPv8-capable, the sender constructs a full
   IPv8 packet:

   Version field:       8
   Source address:      r.r.r.r.n.n.n.n  (64-bit, full prefix)
   Destination address: r.r.r.r.n.n.n.n  (64-bit, full prefix)

   For a neighbor recorded as IPv4-only, the sender constructs a
   standard IPv4 packet:

   Version field:       4
   Source address:      n.n.n.n  (32-bit, host portion only)
   Destination address: n.n.n.n  (32-bit, host portion only)

   The r.r.r.r prefix is not present on the wire for that hop.  The IPv4
   neighbor receives a packet indistinguishable from normal IPv4.  An
   IPv4-only device on a shared segment with IPv8-capable devices never
   receives a packet with version 8 in the IP header.  The mismatched-
   version drop case never arises because the IPv8 sender constructs the
   packet in the version the neighbor understands.

2.4.  Router Forwarding

   An IPv8 router forwarding to a next-hop IPv4-only neighbor applies
   the same rule.  If a packet arrived as IPv8 on the inbound interface
   and the next hop is recorded as IPv4-only, the router MUST downgrade
   at the outgoing interface:

   Inbound:   version 8, r.r.r.r.n.n.n.n source and destination
   Outbound:  version 4, n.n.n.n source and destination

   The r.r.r.r prefix is stripped from the source address.  Session
   state is preserved via XLATE8 on the Zone Server for return traffic
   reconstruction.  The IPv4 device on the outgoing segment receives a
   standard IPv4 packet and has no knowledge of IPv8 upstream.

   A single IPv8 router MAY serve IPv8-capable and IPv4-only devices on
   different interfaces simultaneously, applying version selection
   independently per outgoing interface based on the ARP8-recorded
   capability of each next-hop neighbor.




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2.5.  Attribution at IPv4 Hops

   When a packet is transmitted as IPv4 -- either host-to-IPv4- neighbor
   or router-downgraded at an IPv4 boundary -- the r.r.r.r prefix is not
   on the wire for that hop.  ASN attribution and WHOIS8 validation
   apply only to hops where both endpoints are IPv8-capable.  This is an
   accepted and correct property of the transition model: IPv4
   communications do not carry IPv8 properties, in the same way that
   IPv4 communications today do not carry RPKI validation unless both
   endpoints support it.

2.6.  Transition Properties

   This model produces the following transition properties:

   *  IPv4-only endpoints never require modification.
   *  IPv4 devices on a shared segment with IPv8 devices continue to
      operate without configuration change.
   *  IPv4 devices behind IPv8 routers continue to operate because the
      router downgrades at the boundary.
   *  IPv4 applications on IPv8 hosts continue to operate because XLATE8
      handles version translation on their behalf.
   *  No IPv4 device ever receives a packet with version 8 in the IP
      header.
   *  Transition is per-device and per-router, on each operator's own
      schedule, with no flag day and no coordination requirement between
      operators.

   Four lines of configuration enable IPv8 on a router.  No existing
   IPv4 device, application, or network requires any modification.

3.  Motivation and Problem Statement

3.1.  Management Fragmentation

   IPv4 network management has no coherent integrated model.  The
   protocols that operate a network -- DHCP, DNS, NTP, syslog, SNMP,
   authentication -- were specified independently over four decades,
   share no common identity model, no common authentication mechanism,
   and no common telemetry format.

   The consequences are operational: networks require specialist
   knowledge of each protocol independently.  Security is inconsistent
   -- some services require authentication, others accept
   unauthenticated requests from any source.  Failures require
   correlating logs across systems with different timestamp formats,
   different severity models, and different identity representations.
   Management scales with operational burden, not with network size.



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   IPv8 addresses this by defining a coherent management suite in which
   every service shares a common identity model (OAuth2 JWT), a common
   delivery mechanism (DHCP8), a common telemetry format (NetLog8), and
   a common authentication cache (OAuth8).

3.2.  Address Exhaustion

   IANA completed allocation of the IPv4 unicast address space in
   February 2011.  Regional Internet Registries exhausted their
   allocations between 2011 and 2020.  CGNAT extended IPv4 life at the
   cost of latency, peer-to-peer protocol breakage, and troubleshooting
   complexity.

   IPv6 [RFC8200] was developed to address exhaustion.  After 25 years
   of standardisation and deployment effort IPv6 carries a minority of
   global internet traffic.  The dual-stack transition model --
   requiring every device, application, and network to simultaneously
   support both protocols -- proved commercially unacceptable.  The
   absence of a forcing function meant organisations could continue with
   CGNAT indefinitely.

   IPv8 resolves address exhaustion without dual-stack operation.  IPv4
   is a proper subset of IPv8.  The transition requires no flag day and
   creates no operational discontinuity.

3.3.  Routing Table Growth

   The BGP4 global routing table exceeded 900,000 prefixes in 2024 and
   grows without architectural bound.  Prefix deaggregation --
   advertising more specific prefixes to influence traffic engineering
   -- is the primary driver of growth.  No protocol mechanism prevents
   it.

   BGP4 has no binding relationship between what an ASN advertises and
   what it is authorised to advertise.  Prefix hijacking, route leaks,
   and bogon injection are possible because there is no route ownership
   registry that border routers enforce as a condition of route
   acceptance.

   IPv8 addresses both problems.  The /16 minimum injectable prefix rule
   prevents deaggregation at inter-AS boundaries.  WHOIS8 mandatory
   route validation creates a binding relationship between BGP8
   advertisements and registered route ownership -- WHOIS8 is a critical
   infrastructure service for the global routing system.  The global
   BGP8 routing table is bounded by the number of /16 prefixes held
   across all active ASNs, a structurally finite set.





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3.4.  Requirements for a Viable Successor

   *  R1.  Integrated management -- common identity, authentication,
      telemetry, and service delivery across all network services.
   *  R2.  Single stack operation -- no dual-stack requirement.
   *  R3.  Full backward compatibility -- existing IPv4 applications
      unchanged.  IPv4 is a proper subset of IPv8.
   *  R4.  Full backward compatibility -- RFC 1918 internal networks
      unchanged.
   *  R5.  Full backward compatibility -- CGNAT deployments unchanged.
   *  R6.  Vastly expanded address space.
   *  R7.  Implementable as a software update without hardware
      replacement.
   *  R8.  Human readable addressing consistent with IPv4 operator
      familiarity.
   *  R9.  East-west and north-south traffic security enforced by
      protocol, not by manual configuration.
   *  R10.  Structurally bounded global routing table.

   IPv8 satisfies all ten requirements.

4.  IPv8 Address Format

4.1.  Structure

   An IPv8 address is a 64-bit value:

   r.r.r.r.n.n.n.n

   *  *r.r.r.r* -- 32-bit ASN Routing Prefix
   *  *n.n.n.n* -- 32-bit Host Address (identical semantics to IPv4)

4.2.  Address Space

   2^64 = 18,446,744,073,709,551,616 unique addresses.
   2^32 ASN prefixes x 2^32 host addresses per ASN.

4.3.  IPv4 Representation in IPv8

   0.0.0.0.n.n.n.n

   Packets with r.r.r.r = 0.0.0.0 MUST be routed using standard IPv4
   rules applied to the n.n.n.n field.  IPv4 is a proper subset of IPv8.
   No modification to IPv4 devices, applications, or networks is
   required.






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4.4.  ASN Encoding in r.r.r.r

   The 32-bit ASN is encoded directly into r.r.r.r as a 32-bit unsigned
   integer in network byte order:

   ASN 64496 (Example-A)   = 0.0.251.240
   ASN 64497 (Example-B)   = 0.0.251.241
   ASN 64498 (Example-C)   = 0.0.251.242

4.5.  Internal Zone Prefix (127.0.0.0/8)

   The 127.0.0.0/8 range of the r.r.r.r field is permanently reserved
   for internal IPv8 zone prefixes.  Internal zone prefixes identify
   network zones within an organisation's private addressing space.

   127.x.x.x.n.n.n.n

   Where x.x.x identifies the internal zone.  Examples:

   127.1.0.0.n.n.n.n   Internal zone 1 (e.g. Americas)
   127.2.0.0.n.n.n.n   Internal zone 2 (e.g. Europe)
   127.3.0.0.n.n.n.n   Internal zone 3 (e.g. Asia Pacific)

   Internal zone prefix rules:

   *  MUST NOT be routed externally beyond the organisation's AS
      boundary.
   *  MUST NOT appear on WAN interfaces or public internet links.
   *  MUST NOT be used in eBGP8 advertisements.
   *  MAY be used freely within an organisation's internal routing
      infrastructure via OSPF8, IS-IS8, and IBGP8.
   *  Provides 2^56 effective internal addresses across all zone
      prefixes.  No internal address conflict is possible between zones.
   *  Enables organisations to build geographically distributed, region-
      routed private networks of arbitrary scale without external
      address coordination.

   ASN numbers that encode to the 127.0.0.0/8 range in the r.r.r.r field
   (ASN 2130706432 through ASN 2147483647) are reserved for internal
   zone use and MUST NOT be allocated by IANA for public internet
   routing.










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4.6.  Inter-Company Interop Prefix (127.127.0.0)

   The 127.127.0.0 prefix is reserved as the standard inter- company
   interoperability DMZ.  When two organisations need to interconnect
   without exposing their internal zone addressing, both deploy XLATE8
   engines facing a shared 127.127.0.0 address space.  Full
   specification in [ZONESERVER] Section 16.9.

4.7.  Two-XLATE8 Interop Model

   Company A                          Company B
   ---------                          ---------
   127.1.0.0.x   XLATE8-A  127.127.0.0  XLATE8-B  127.2.0.0.x

   Properties:

   *  Company A never sees Company B's 127.2.0.0 addresses.
   *  Company B never sees Company A's 127.1.0.0 addresses.
   *  Each company controls exactly what it exposes.
   *  No address overlap possible.  No NAT complexity.
   *  Setup time: minutes per service exposed.

4.8.  Private Interop ASN (ASN 65534)

   ASN 65534 is reserved for private inter-company BGP8 peering
   consistent with [RFC6996]:

   0.0.255.254.x.x.x.x

   ASN 65533 (0.0.255.253.x.x.x.x) is reserved for documentation and
   testing purposes.

4.9.  RINE Peering Prefix (100.0.0.0/8)

   The 100.0.0.0/8 range of the r.r.r.r field is permanently reserved
   for the Regional Inter-Network Exchange (RINE) peering fabric.  RINE
   addresses are used exclusively for AS-to-AS peering link addressing
   at IXPs and private interconnect facilities.  Full specification in
   [RINE].

   RINE addresses:

   *  MUST NOT be advertised in the global BGP8 routing table.
   *  MUST NOT be assigned to end devices.
   *  MUST be filtered at all eBGP8 border routers.






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4.10.  Interior Link Convention (222.0.0.0/8)

   The n.n.n.n range 222.0.0.0/8 is the well-known IPv8 interior link
   address convention.  Every AS MAY use <own-asn>.222.x.x.x for router-
   to-router interior link addressing within their AS.

   This convention is analogous to RFC 1918 [RFC1918] for IPv4 --
   universally recognised, universally filtered, never routed
   externally, never an endpoint.

4.11.  Address Usage Model

    +=====================+===============================+===========+
    | Address Space       | Usage                         | Routable  |
    +=====================+===============================+===========+
    | 127.x.x.x.n.n.n.n   | Internal devices (all zones)  | Never     |
    +---------------------+-------------------------------+-----------+
    | 127.127.0.0.n.n.n.n | Inter-company interop DMZ     | Private   |
    +---------------------+-------------------------------+-----------+
    | 100.x.x.x.n.n.n.n   | RINE peering links only       | Never     |
    +---------------------+-------------------------------+-----------+
    | <asn>.222.x.x.x     | Interior router links         | Never     |
    +---------------------+-------------------------------+-----------+
    | 0.0.255.254.n.n.n.n | Private BGP8 peering          | Private   |
    +---------------------+-------------------------------+-----------+
    | <own-asn>.n.n.n.n   | Explicit public services only | Global    |
    +---------------------+-------------------------------+-----------+
    | 0.0.0.0.n.n.n.n     | IPv4 compatible (r.r.r.r = 0) | IPv4 only |
    +---------------------+-------------------------------+-----------+

                                  Table 1

   Most devices on most networks use 127.x.x.x internal addressing.
   Public ASN addresses are used only for explicitly public-facing
   services.

5.  Address Classes

      +=================+=================+========================+
      | r.r.r.r Value   | Class           | Description            |
      +=================+=================+========================+
      | 0.0.0.0         | IPv4 Compatible | Route on n.n.n.n using |
      |                 |                 | IPv4 rules             |
      +-----------------+-----------------+------------------------+
      | 0.0.0.1 through | ASN Unicast     | Route to ASN, deliver  |
      |                 |                 | to n.n.n.n             |
      +-----------------+-----------------+------------------------+
      | 99.255.255.255  |                 | Public internet        |



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      |                 |                 | routing via eBGP8      |
      +-----------------+-----------------+------------------------+
      | 100.0.0.0       | RINE Peering    | AS-to-AS peering link  |
      | through         |                 | addressing             |
      +-----------------+-----------------+------------------------+
      | 100.255.255.255 |                 | MUST NOT be globally   |
      |                 |                 | routed                 |
      +-----------------+-----------------+------------------------+
      | 101.0.0.0       | ASN Unicast     | Route to ASN, deliver  |
      | through         |                 | to n.n.n.n             |
      +-----------------+-----------------+------------------------+
      | 126.255.255.255 |                 | Public internet        |
      |                 |                 | routing via eBGP8      |
      +-----------------+-----------------+------------------------+
      | 127.0.0.0       | Internal Zone   | Internal zone          |
      | through         | Prefix          | identifier             |
      +-----------------+-----------------+------------------------+
      | 127.255.255.255 |                 | MUST NOT be routed     |
      |                 |                 | externally             |
      +-----------------+-----------------+------------------------+
      | 128.0.0.0       | ASN Unicast     | Route to ASN, deliver  |
      | through         |                 | to n.n.n.n             |
      +-----------------+-----------------+------------------------+
      | ff.fe.ff.ff     |                 | Public internet        |
      |                 |                 | routing via eBGP8      |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.00     | Cross-ASN       | General cross-ASN      |
      |                 | Multicast       | multicast              |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.01     | OSPF8 Reserved  | OSPF8 protocol         |
      |                 |                 | multicast traffic      |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.02     | BGP8 Reserved   | BGP8 peer discovery    |
      |                 |                 | multicast              |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.03     | EIGRP Reserved  | Reserved.  Deprecated. |
      |                 |                 | Vendor ext.            |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.04     | RIP Reserved    | Reserved.  Deprecated. |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.05     | IS-IS8 Reserved | IS-IS8.  Vendor        |
      |                 |                 | extensible.            |
      +-----------------+-----------------+------------------------+
      | ff.ff.00.06     | Cross-ASN       | Available for future   |
      | through         | Multicast       | IANA                   |
      +-----------------+-----------------+------------------------+
      | ff.ff.ef.ff     | (available)     | assignment.            |
      +-----------------+-----------------+------------------------+



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      | ff.ff.f0.00     | Reserved        | Future use.            |
      | through         |                 |                        |
      +-----------------+-----------------+------------------------+
      | ff.ff.fe.ff     |                 |                        |
      +-----------------+-----------------+------------------------+
      | ff.ff.ff.ff     | Broadcast       | Maps to L2 broadcast.  |
      +-----------------+-----------------+------------------------+
      |                 |                 | MUST NOT be routed.    |
      +-----------------+-----------------+------------------------+

                                 Table 2

   The n.n.n.n range 222.0.0.0/8 is reserved by convention for interior
   link addressing per Section 3.10.

5.1.  Anycast

   Anycast is not a separate address class in IPv8.  Anycast is a
   routing property implemented via eBGP8.  The Cost Factor (CF) metric
   defined in [ROUTING-PROTOCOLS] routes each packet to the nearest BGP8
   instance by measured cost automatically.

6.  IPv8 Packet Header

6.1.  Header Format

   IPv8 uses IP version number 8 in the Version field.  The header
   extends IPv4 by replacing the 32-bit src/dst address fields with
   64-bit equivalents.

   <CODE BEGINS>




















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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Version|  IHL  |Type of Service|          Total Length         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         Identification        |Flags|      Fragment Offset    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Time to Live |    Protocol   |         Header Checksum       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Source ASN Prefix (r.r.r.r)                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Source Host Address (n.n.n.n)              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 Destination ASN Prefix (r.r.r.r)              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 Destination Host Address (n.n.n.n)            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   <CODE ENDS>

   The IPv8 header is 8 octets longer than the IPv4 header.

6.2.  Socket API Compatibility

   Existing IPv4 applications use the standard BSD socket API with
   AF_INET and sockaddr_in.  The IPv8 compatibility layer intercepts
   socket calls transparently -- the application has zero IPv8
   awareness.  New applications MAY use AF_INET8 with sockaddr_in8:

   struct sockaddr_in8 {
       sa_family_t    sin8_family;   /* AF_INET8 */
       in_port_t      sin8_port;     /* port number */
       uint32_t       sin8_asn;      /* r.r.r.r ASN prefix */
       struct in_addr sin8_addr;     /* n.n.n.n host address */
   };

7.  ASN Dot Notation

   Format: <ASN>.<n>.<n>.<n>.<n>

   Where ASN is the autonomous system number and n.n.n.n is the host
   address.  Example ASNs 64496-64511 are reserved for documentation per
   [RFC5398].

   64496.192.0.2.1  = 0.0.251.240.192.0.2.1  (Example-A)
   64497.192.0.2.1  = 0.0.251.241.192.0.2.1  (Example-B)





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   All IPv8-compliant implementations MUST accept ASN Dot Notation in
   all contexts where an IPv8 address is accepted.

8.  DNS A8 Record Type

   *  *Type:* A8 (IANA assignment pending)
   *  *Format:* 64-bit IPv8 address in network byte order
   *  RFC 1918 addresses MUST NOT be published as A8 records in public
      DNS.
   *  An IPv8 resolver SHOULD request both A and A8 records.
   *  For IPv4 applications on IPv8 hosts, the resolver returns the
      n.n.n.n portion; the stack prepends r.r.r.r transparently.
   *  A8 responses SHOULD be an even/odd pair -- one even address and
      one odd address.  Even addresses are served via the even Zone
      Server gateway (.254) and odd addresses via the odd Zone Server
      gateway (.253).  This enables clients to open parallel streams to
      the same host across independent gateway paths, providing load
      distribution and redundancy without stateful load balancer
      infrastructure.  Administrators MAY deviate from this convention
      where operational requirements justify it.

   Example records:

   ns1.example.com.  IN  A8  0.0.59.65.192.0.2.1
   ns1.example.com.  IN  A8  0.0.59.65.192.0.2.2

9.  Routing Protocol Behaviour

9.1.  Mandatory Routing Protocols

      +==========+============+=======================+============+
      | Protocol | Scope      | Function              | Status     |
      +==========+============+=======================+============+
      | eBGP8    | Inter-AS   | Mandatory EGP for     | MANDATORY  |
      |          |            | public internet       |            |
      +----------+------------+-----------------------+------------+
      | IBGP8    | Inter-zone | Mandatory for         | MANDATORY  |
      |          |            | internal zone routing |            |
      +----------+------------+-----------------------+------------+
      | OSPF8    | Intra-zone | Mandatory for intra-  | MANDATORY  |
      |          |            | zone routing          |            |
      +----------+------------+-----------------------+------------+
      | IS-IS8   | Intra-AS   | Available in all L3   | MUST BE    |
      |          |            | stacks                | AVAIL.     |
      +----------+------------+-----------------------+------------+
      | Static   | All scopes | Mandatory for legacy  | MANDATORY  |
      |          |            | and VRF routing       |            |
      +----------+------------+-----------------------+------------+



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      | BGP4     | Transition | IPv4 AS compatibility | TRANSITION |
      +----------+------------+-----------------------+------------+

                                 Table 3

9.2.  Deprecated Routing Protocols

            +===========+================+===================+
            | Protocol  | Status in IPv8 | Notes             |
            +===========+================+===================+
            | RIP/RIPv2 | DEPRECATED     | Replaced by OSPF8 |
            +-----------+----------------+-------------------+
            | EIGRP     | DEPRECATED     | Vendor extensible |
            +-----------+----------------+-------------------+

                                 Table 4

9.3.  eBGP8 - Mandatory Exterior Gateway Protocol

   eBGP8 is the mandatory exterior gateway protocol.  All L3 devices
   MUST implement eBGP8. eBGP8 is 100% backward compatible with BGP4
   [RFC4271].  Full specification in [ROUTING-PROTOCOLS].

   The minimum injectable prefix at inter-AS boundaries is /16.
   Prefixes more specific than /16 MUST NOT be advertised across AS
   boundaries.

9.4.  IBGP8 - Inter-Zone Routing

   IBGP8 distributes WHOIS8-validated external routes throughout an
   autonomous system with full CF metric awareness.

   CF_total = CF_external + CF_intrazone

9.5.  OSPF8 - Intra-Zone Routing

   OSPF8 is OSPFv2 [RFC2328] extended with a CF export interface.  All
   L3 devices MUST implement OSPF8.  Full specification in
   [ROUTING-PROTOCOLS] Section 10.3.

9.6.  IS-IS8 - Optional Interior Gateway Protocol

   IS-IS8 MUST be available in all IPv8 L3 routing stacks.  Carriers and
   operators MAY deploy IS-IS8 at their discretion.  IPv8 makes no
   recommendation regarding IGP selection.  Full specification in
   [ROUTING-PROTOCOLS] Section 10.4.





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9.7.  Two-Tier Routing Table

     +======+========+=========+====================================+
     | Tier | Scope  | Index   | Description                        |
     +======+========+=========+====================================+
     | 1    | Global | r.r.r.r | Routes to correct AS border router |
     +------+--------+---------+------------------------------------+
     | 2    | Local  | n.n.n.n | Identical to existing IPv4 routing |
     |      |        |         | table                              |
     +------+--------+---------+------------------------------------+

                                 Table 5

   When r.r.r.r = 0.0.0.0 the Tier 1 lookup is bypassed.

9.8.  VRF - Virtual Routing and Forwarding

   VRF is mandatory for all IPv8 L3 devices.  The management VRF (VLAN
   4090) and OOB VRF (VLAN 4091) MUST be implemented on all
   IPv8-compliant devices.  VRF isolation is a routing table property
   that cannot be bypassed by software misconfiguration.

10.  ICMPv8

   ICMPv8 extends ICMP [RFC792] to support 64-bit IPv8 addresses.
   ICMPv8 is backward compatible with ICMPv4.  Both versions MUST be
   supported simultaneously.  ICMPv8 carries full 64-bit IPv8 addresses
   in Echo, Destination Unreachable, Time Exceeded, Redirect, and
   Parameter Problem messages.  Path MTU Discovery is extended for the
   larger IPv8 header.

   ICMPv8 version selection follows the ARP8 rule defined in Section 2:
   ICMPv8 messages transmitted to an IPv4-only neighbor MUST be
   constructed as ICMPv4 with 32-bit addresses.  An IPv4-only device
   never receives an ICMPv8 message.  Full specification in [SUPPORT8].

11.  Multicast

11.1.  Intra-ASN Multicast

   0.0.0.0.224.0.0.0/4   All intra-ASN multicast
   0.0.0.0.239.0.0.0/8   Administratively scoped intra-ASN

   Packets with r.r.r.r = 0.0.0.0 and n.n.n.n in the multicast range
   MUST NOT be forwarded beyond the local AS boundary.

11.2.  Cross-ASN Multicast




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   ff.ff.00.00.n.n.n.n   General cross-ASN multicast
   ff.ff.00.01.n.n.n.n   OSPF8 protocol traffic
   ff.ff.00.02.n.n.n.n   BGP8 peer discovery
   ff.ff.00.03.n.n.n.n   EIGRP (reserved, deprecated)
   ff.ff.00.04.n.n.n.n   RIP (reserved, deprecated)
   ff.ff.00.05.n.n.n.n   IS-IS8 (reserved, vendor ext.)

11.3.  Cross-ASN Multicast Group Assignments

   ff.ff.00.00.224.0.0.1    All IPv8 routers
   ff.ff.00.00.224.0.0.2    All IPv8 Zone Servers
   ff.ff.00.00.224.0.0.5    OSPF8 all routers
   ff.ff.00.00.224.0.0.6    OSPF8 designated routers
   ff.ff.00.00.224.0.0.10   IBGP8 peer discovery
   ff.ff.00.00.239.0.0.0/8  Administratively scoped

12.  Anycast

   Anycast in IPv8 is a routing property implemented via eBGP8 and the
   Cost Factor (CF) metric.  No special r.r.r.r prefix is required.  CF
   routes each packet to the nearest instance by measured path cost.

13.  Broadcast

   The r.r.r.r value ff.ff.ff.ff is permanently reserved for broadcast
   and maps to the Layer 2 broadcast address.  Packets with r.r.r.r =
   ff.ff.ff.ff MUST NOT be routed beyond the local network segment.

14.  Compatibility and Transition

14.1.  Single Stack Operation

   IPv8 does not require dual-stack operation.  IPv4 is a proper subset
   of IPv8 with r.r.r.r = 0.0.0.0.  There is no flag day and no forced
   migration.

14.2.  IPv4 Network Compatibility

   Networks that have not deployed IPv8 continue to operate unchanged.
   IPv8 border routers apply ARP8-driven version selection at each
   outgoing interface: the r.r.r.r prefix is stripped and the packet is
   downgraded to IPv4 for any next-hop neighbor recorded as IPv4-only in
   the ARP8 cache.  No configuration is required on the IPv4 side.








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14.3.  8to4 - IPv8 Across IPv4-Only Networks

   IPv8 traverses IPv4-only networks without pre-configured tunnels.  A
   large service provider MAY leave their entire IPv4 core unchanged for
   20 years.  IPv8 traffic traverses it automatically using per-hop
   anycast encapsulation.

   Every ASN publishes an IPv4 anycast address in its WHOIS8 record.
   All BGP8 edge routers in that ASN advertise this address into the
   surrounding BGP4 fabric as a normal IPv4 route.  The global BGP4
   table carries it with zero modification.  When a BGP8 router needs to
   reach a destination ASN across IPv4-only hops, it looks up the
   destination ASN in its WHOIS8 cache, gets the anycast address,
   encapsulates the IPv8 packet in a standard IPv4 envelope addressed to
   that anycast address, and forwards it.  IPv4-only routers in the core
   forward the outer IPv4 packet using normal routing.  The nearest BGP8
   edge router for the destination ASN decapsulates and delivers.

   This model requires zero tunnel configuration on any device.  All
   available paths through the IPv4 core are used by normal BGP4 path
   selection.  A network that would have required 100,000 pre-configured
   tunnels under the tunnel model requires zero under the anycast model.

   Full specification in [ROUTING-PROTOCOLS] Section 11.

14.4.  Transition Sequence

   Phase 1: Tier 1/2 ISP routers deploy IPv8 via software update.
   Phase 2: Cloud providers deploy IPv8 internally.
   Phase 3: Enterprise networks optionally adopt ASN prefixes.
   Phase 4: Consumer ISPs deploy IPv8.

   8to4 tunnelling enables each phase to interoperate with phases not
   yet completed.  There is no dependency between phases.

15.  CGNAT Behaviour

   CGNAT devices require no modification.  IPv8-aware CGNAT MUST NOT
   modify the r.r.r.r field during translation.  Only the n.n.n.n field
   is subject to NAT translation.  CGNAT operators without an ASN MUST
   use r.r.r.r = 0.0.0.0.










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15.1.  XLATE8 Even/Odd Load Balancing

   When an IPv4 client connects to an IPv8 host via an XLATE8 gateway,
   the destination host may have both an even and an odd A8 address.
   The XLATE8 gateway SHOULD pass both addresses through to the IPv4
   client where the client is capable of using both.  Where the IPv4
   client is not capable, the XLATE8 gateway MAY perform load balancing
   internally, distributing connections across the even and odd
   addresses of the destination host.  This provides IPv4 clients with
   the benefit of IPv8 even/odd load distribution transparently.

16.  Application Compatibility

   Existing IPv4 applications require no modification.  The IPv8 socket
   compatibility layer transparently manages r.r.r.r via DNS8
   interception and XLATE8.  New applications MAY use AF_INET8 and
   sockaddr_in8 as defined in Section 5.2.

17.  Cloud Provider Applicability

   IPv8 resolves VPC address overlap, VPC peering complexity, and multi-
   cloud routing through ASN-based disambiguation.  The 127.x.x.x
   internal zone prefix enables cloud providers to assign unique zone
   prefixes to customer VPCs without address renumbering.  Each customer
   VPC receives a unique 127.x.x.x zone prefix -- no two customer
   networks can overlap regardless of RFC 1918 address reuse within each
   VPC.

18.  Device Compliance Tiers

18.1.  Tier 1 - End Device

   End devices MUST implement: Route8 unified routing table, static
   routes, VRF (management plane), two default gateways (even Zone
   Server .254, odd Zone Server .253), DHCP8 client, ARP8, ICMPv8,
   TCP/443 persistent connection to Zone Server, NetLog8 client, ACL8
   client-side enforcement, management VRF (VLAN 4090), OOB VRF (VLAN
   4091), gratuitous ARP8 on boot.

   End devices SHOULD use the even gateway for even-addressed traffic
   and the odd gateway for odd-addressed traffic, failing over to the
   surviving gateway on failure.  Dual-NIC end devices SHOULD request
   one even and one odd address from DHCP8.

   End devices MAY implement: OSPF8, IS-IS8, eBGP8, IBGP8.

   End devices DO NOT require any routing protocol to reach their
   default gateway.



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18.2.  Tier 2 - L2 Network Device

   L2 devices MUST implement: 802.1Q trunking, VLAN auto- creation on
   tagged traffic, management VRF (VLAN 4090), OOB VRF (VLAN 4091),
   switch port OAuth2 binding, LLDP, NetLog8 client, ARP8 (management
   plane only), ICMPv8 (management plane only), PVRST, Zone Server as
   PVRST root capability, sticky MAC binding, Zone Server MAC
   notification.

18.3.  Tier 3 - L3 Network Device

   L3 devices MUST implement: All Tier 1 requirements, eBGP8, IBGP8,
   OSPF8, IS-IS8 (available), static routes, VRF (full), XLATE8
   (mandatory on edge devices), WHOIS8 resolver, ACL8 gateway
   enforcement, Zone Server services (if Zone Server role), PVRST root
   capability, switch port OAuth2 binding support.

18.4.  Spanning Tree - PVRST Mandatory

   PVRST is mandatory for all IPv8 L2 and L3 devices.  MST is not
   recommended.  Zone Servers are PVRST roots by default:

   *  Primary Zone Server (.254): PVRST root for even VLANs, priority
      4096.
   *  Secondary Zone Server (.253): PVRST root for odd VLANs, priority
      4096.

18.5.  NIC Broadcast Rate Limits

   IPv8 certified NIC firmware enforces broadcast and control packet
   rate limits that cannot be overridden by software.  These limits
   apply to broadcast and unauthenticated traffic only and do not
   constrain unicast data throughput:

   Broadcasts:            10 per second maximum
   User unauthenticated:  10 per second, max 30 per minute
   User authenticated:    100 per second, max 300 per minute

   The DHCP8 Zone Server is the sole authority for rate limit elevation.
   Full NIC certification specification in [UPDATE8].

19.  Security Considerations

19.1.  ASN Prefix Spoofing

   IPv8 border routers MUST implement ingress filtering validating that
   the source r.r.r.r of received packets matches the ASN of the BGP8
   peer.  Consistent with BCP 38 [RFC2827].



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19.2.  Internal Zone Prefix Protection

   The 127.x.x.x internal zone prefix MUST NOT appear on WAN interfaces.
   Border routers MUST drop packets with 127.x.x.x source or destination
   r.r.r.r on external interfaces.  NetLog8 SEC-ALERT MUST be generated
   for each violation.

19.3.  RINE Prefix Protection

   The 100.x.x.x RINE prefix MUST NOT appear in eBGP8 advertisements or
   on non-peering interfaces.  NetLog8 SEC-ALERT MUST be generated for
   each violation.

19.4.  Interior Link Convention Protection

   Border routers MUST filter received BGP8 advertisements containing
   n.n.n.n addresses in the 222.0.0.0/8 range.  NetLog8 E3 trap MUST be
   generated for each violation.

19.5.  RFC 1918 Address Privacy

   RFC 1918 private addresses in n.n.n.n remain non-routable on the
   public internet consistent with IPv4 behaviour.

19.6.  Cross-ASN Multicast Filtering

   Routing protocol reserved prefixes ff.ff.00.01 through ff.ff.00.05
   MUST be filtered at all border routers.

19.7.  /16 Minimum Prefix Enforcement

   Prefixes more specific than /16 MUST NOT be accepted from external
   BGP8 peers.  Such advertisements MUST be rejected and logged via
   NetLog8 as SEC-ALERT.

20.  IANA Considerations

20.1.  IP Version Number

   IANA is requested to assign version number 8 in the IP Version Number
   registry to Internet Protocol Version 8.

20.2.  Internal Zone Prefix Reservation

   IANA is requested to reserve the r.r.r.r range 127.0.0.0 through
   127.255.255.255 as the IPv8 internal zone prefix space.  ASN numbers
   2130706432 through 2147483647 MUST NOT be allocated for public
   internet routing.



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20.3.  RINE Prefix Reservation

   IANA is requested to reserve the r.r.r.r range 100.0.0.0 through
   100.255.255.255 as the IPv8 RINE peering fabric range.  ASN numbers
   1677721600 through 1694498815 MUST NOT be allocated for public
   internet routing.

20.4.  Interior Link Convention

   IANA is requested to document the n.n.n.n range 222.0.0.0/8 as the
   IPv8 interior link address convention.

20.5.  Cross-ASN Multicast Range

   IANA is requested to establish a registry for IPv8 cross-ASN
   multicast prefixes within ff.ff.00.00 through ff.ff.ef.ff.

20.6.  Broadcast Reservation

   IANA is requested to reserve r.r.r.r value ff.ff.ff.ff as the IPv8
   broadcast address.

20.7.  DNS A8 Record Type

   IANA is requested to assign a DNS resource record type number for the
   A8 record type defined in Section 7.

20.8.  Multicast Group Assignments

   IANA is requested to assign multicast groups within
   ff.ff.00.00.224.0.0.0/24 as defined in Section 10.3.

20.9.  Private ASN Reservations

   IANA is requested to reserve ASN 65534 for private inter- company
   BGP8 peering and ASN 65533 for documentation and testing purposes
   consistent with [RFC6996].

21.  Informative References

   [RFC1918]  Rekhter, Y., "Address Allocation for Private Internets",
              BCP 5, RFC 1918, February 1996,
              <https://www.rfc-editor.org/info/rfc1918>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.




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   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998,
              <https://www.rfc-editor.org/info/rfc2328>.

   [RFC2827]  Ferguson, P. and D. Senie, "Network Ingress Filtering",
              BCP 38, RFC 2827, May 2000,
              <https://www.rfc-editor.org/info/rfc2827>.

   [RFC4271]  Rekhter, Y., "A Border Gateway Protocol 4 (BGP-4)",
              RFC 4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [RFC5398]  Huston, G., "Autonomous System (AS) Numbers Reserved for
              Documentation Use", RFC 5398, December 2008,
              <https://www.rfc-editor.org/info/rfc5398>.

   [RFC6996]  Mitchell, J., "Autonomous System (AS) Reservation for
              Private Use", BCP 6, RFC 6996, July 2013,
              <https://www.rfc-editor.org/info/rfc6996>.

   [RFC7519]  Jones, M., "JSON Web Token (JWT)", RFC 7519, May 2015,
              <https://www.rfc-editor.org/info/rfc7519>.

   [RFC792]   Postel, J., "Internet Control Message Protocol", STD 5,
              RFC 792, September 1981,
              <https://www.rfc-editor.org/info/rfc792>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, May 2017,
              <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8200]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", STD 86, RFC 8200, July 2017,
              <https://www.rfc-editor.org/info/rfc8200>.

   [RINE]     Thain, J., "Regional Inter-Network Exchange", Work in
              Progress, Internet-Draft, draft-thain-rine-00, April 2026,
              <https://datatracker.ietf.org/doc/html/draft-thain-rine-
              00>.

   [ROUTING-PROTOCOLS]
              Thain, J., "IPv8 Routing Protocols", Work in Progress,
              Internet-Draft, draft-thain-routing-protocols-00, April
              2026, <https://datatracker.ietf.org/doc/html/draft-thain-
              routing-protocols-00>.







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   [SUPPORT8] Thain, J., "IPv8 Support Protocols -- ARP8, ICMPv8, and
              Route8", Work in Progress, Internet-Draft, draft-thain-
              support8-00, April 2026,
              <https://datatracker.ietf.org/doc/html/draft-thain-
              support8-00>.

   [UPDATE8]  Thain, J., "Update8 and NIC Certification", Work in
              Progress, Internet-Draft, draft-thain-update8-00, April
              2026, <https://datatracker.ietf.org/doc/html/draft-thain-
              update8-00>.

   [ZONESERVER]
              Thain, J., "IPv8 Zone Server Architecture", Work in
              Progress, Internet-Draft, draft-thain-zoneserver-00, April
              2026, <https://datatracker.ietf.org/doc/html/draft-thain-
              zoneserver-00>.

Author's Address

   Jamie Thain
   One Limited
   Hamilton
   Bermuda
   Email: jamie@one.bm



























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