anycast

An IP prefix may be configured as anycast and, as such, the same value can be advertised by multiple routers. It is useful for other routers to know that the advertisement is for an anycast prefix.

This document defines a new flag in the OSPFv2 Extended Prefix TLV Flags to advertise the anycast property. The document also specifies a companion YANG module for managing this function.

This document updates the 6LoWPAN extensions to IPv6 Neighbor Discovery (specified in RFCs 4861 and 8505) to enable a listener to subscribe to an IPv6 anycast or multicast address. This document also updates the Routing Protocol for Low-Power and Lossy Networks (RPL) (specified in RFCs 6550 and 6553) to add a new Non-Storing multicast mode and new support for anycast addresses in Storing and Non-Storing modes. This document extends RFC 9010 to enable a 6LoWPAN Router (6LR) to inject the anycast and multicast addresses in RPL.

Recent research work has explored the deployment characteristics and configuration of the Domain Name System (DNS). This document summarizes the conclusions from these research efforts and offers specific, tangible considerations or advice to authoritative DNS server operators. Authoritative server operators may wish to follow these considerations to improve their DNS services.

It is possible that the results presented in this document could be applicable in a wider context than just the DNS protocol, as some of the results may generically apply to any stateless/short-duration anycasted service.

This document is not an IETF consensus document: it is published for informational purposes.

This document examines the use of Source-Specific Multicast (SSM) across inter-domain peering points for a specified set of deployment scenarios. The objectives are to (1) describe the setup process for multicast-based delivery across administrative domains for these scenarios and (2) document supporting functionality to enable this process.

The Port Control Protocol (PCP) anycast addresses enable PCP clients to transmit signaling messages to their closest PCP-aware on-path NAT, firewall, or other middlebox without having to learn the IP address of that middlebox via some external channel. This document establishes one well-known IPv4 address and one well-known IPv6 address to be used as PCP anycast addresses.

Experience with the 6to4 transition mechanism defined in RFC 3056 ("Connection of IPv6 Domains via IPv4 Clouds") has shown that the mechanism is unsuitable for widespread deployment and use in the Internet when used in its anycast mode. Therefore, this document requests that RFC 3068 ("An Anycast Prefix for 6to4 Relay Routers") and RFC 6732 ("6to4 Provider Managed Tunnels") be made obsolete and moved to Historic status. It recommends that future products should not support 6to4 anycast and that existing deployments should be reviewed. This complements the guidelines in RFC 6343.

Many sites connected to the Internet make use of IPv4 addresses that are not globally unique. Examples are the addresses designated in RFC 1918 for private use within individual sites.

Devices in such environments may occasionally originate Domain Name System (DNS) queries (so-called "reverse lookups") corresponding to those private-use addresses. Since the addresses concerned have only local significance, it is good practice for site administrators to ensure that such queries are answered locally. However, it is not uncommon for such queries to follow the normal delegation path in the public DNS instead of being answered within the site.

It is not possible for public DNS servers to give useful answers to such queries. In addition, due to the wide deployment of private-use addresses and the continuing growth of the Internet, the volume of such queries is large and growing. The AS112 project aims to provide a distributed sink for such queries in order to reduce the load on the corresponding authoritative servers. The AS112 project is named after the Autonomous System Number (ASN) that was assigned to it.

This document describes the steps required to install a new AS112 node and offers advice relating to such a node's operation.

This document obsoletes RFC 6304.

This memo discusses architectural implications of IP anycast and provides some historical analysis of anycast use by various IETF protocols.

Anycast is a deployment technique commonly employed for authoritative-only servers in the Domain Name System (DNS). L-Root, one of the thirteen root servers, is deployed in this fashion.

Various techniques have been used to map deployed anycast infrastructure externally, i.e., without reference to inside knowledge about where and how such infrastructure has been deployed. Motivations for performing such measurement exercises include operational troubleshooting and infrastructure risk assessment. In the specific case of L-Root, the ability to measure and map anycast infrastructure using the techniques mentioned in this document is provided for reasons of operational transparency.

This document describes all facilities deployed at L-Root to facilitate mapping of its infrastructure and serves as documentation for L-Root as a measurable service.

This document makes recommendations regarding the use of unique origin autonomous system numbers (ASNs) per node for globally anycasted critical infrastructure services in order to provide routing system discriminators for a given anycasted prefix. Network management and monitoring techniques, or other operational mechanisms, may employ this new discriminator in whatever manner best accommodates their operating environment. This memo documents an Internet Best Current Practice.

The Internet Key Exchange Protocol version 2 (IKEv2) is a protocol for setting up Virtual Private Network (VPN) tunnels from a remote location to a gateway so that the VPN client can access services in the network behind the gateway. This document defines an IKEv2 extension that allows an overloaded VPN gateway or a VPN gateway that is being shut down for maintenance to redirect the VPN client to attach to another gateway. The proposed mechanism can also be used in Mobile IPv6 to enable the home agent to redirect the mobile node to another home agent. [STANDARDS-TRACK]

As the Internet has grown, and as systems and networked services within enterprises have become more pervasive, many services with high availability requirements have emerged. These requirements have increased the demands on the reliability of the infrastructure on which those services rely.

Various techniques have been employed to increase the availability of services deployed on the Internet. This document presents commentary and recommendations for distribution of services using anycast. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.

This specification allows Anycast-RP (Rendezvous Point) to be used inside a domain that runs Protocol Independent Multicast (PIM) only. Other multicast protocols (such as Multicast Source Discovery Protocol (MSDP), which has been used traditionally to solve this problem) are not required to support Anycast-RP. [STANDARDS-TRACK]

This specification defines the addressing architecture of the IP Version 6 (IPv6) protocol. The document includes the IPv6 addressing model, text representations of IPv6 addresses, definition of IPv6 unicast addresses, anycast addresses, and multicast addresses, and an IPv6 node's required addresses.

This document obsoletes RFC 3513, "IP Version 6 Addressing Architecture". [STANDARDS-TRACK]

This document describes a mechanism to allow for an arbitrary number of Rendevous Points (RPs) per group in a single shared-tree Protocol Independent Multicast-Sparse Mode (PIM-SM) domain. This memo provides information for the Internet community.

This document defines a set of reserved anycast addresses within each subnet prefix, and lists the initial allocation of these reserved subnet anycast addresses. [STANDARDS-TRACK]

This RFC describes an internet anycasting service for IP. The primary purpose of this memo is to establish the semantics of an anycasting service within an IP internet. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.