PIM

This document describes limitations of the existing range of dynamic IPv6 multicast addresses specified in "Allocation Guidelines for IPv6 Multicast Addresses" (RFC 3307). It updates RFC 3307 by replacing these allocations with a new IANA registry in the "IPv6 Multicast Address Space" registry group. The document also defines initial contents of the new registry: a reduced allocation for the Multicast Address Dynamic Client Allocation Protocol (MADCAP) (RFC 2730), a range for Source-Specific Multicast (SSM), a Private Use range, a range for Experimental Use, and Solicited-Node multicast addresses (which were not previously noted in RFC 3307).

This document surveys current problems with existing protocols for automatically assigning multicast IP addresses in zero-configuration (zeroconf) networking environments. It addresses key challenges, such as link-layer address collisions, hardware limitations, multicast snooping inefficiencies, and the need to avoid manual configuration. Based on these challenges, it derives requirements for a lightweight, decentralized solution for dynamically allocating unique multicast group addresses without central coordination.

The document presents explicit requirements covering discovery, allocation, conflict detection and resolution, and lease management. It also evaluates considerations specific to IPv6 and IPv4 multicast address ranges, and identifies approaches that are unsuited for zeroconf deployment. This foundation serves as a reference for developing future solutions for multicast address allocation that operate autonomously within local networks.

The Point-to-Multipoint (P2MP) Policy enables creation of P2MP trees for efficient multipoint packet delivery in a Segment Routing (SR) domain. This document specifies the architecture, signaling, and procedures for SR P2MP Policies with Segment Routing over MPLS (SR-MPLS) and Segment Routing over IPv6 (SRv6). It defines the SR P2MP Policy construct, candidate paths (CPs) of an SR P2MP Policy, and the instantiation of the P2MP tree instances (PTIs) of a CP using Replication segments. Additionally, it describes the required extensions for a controller to support P2MP path computation and provisioning. This document updates RFC 9524.

Segment Routing (SR) Point-to-Multipoint (P2MP) Policies are used to define and manage explicit P2MP paths within a network. These policies are typically calculated via a controller-based mechanism and installed via, e.g., a Path Computation Element (PCE). In other cases, these policies can be installed using the Network Configuration Protocol (NETCONF) / YANG or a Command Line Interface (CLI). They are used to steer Multicast traffic along optimized paths from a Root to a set of Leaf routers.

This document defines extensions to ping and traceroute mechanisms for an SR P2MP Policy with MPLS encapsulation to provide Operations, Administration, and Maintenance (OAM) capabilities. The extensions enable operators to verify connectivity, diagnose failures, and troubleshoot forwarding issues within SR P2MP Policy Multicast trees.

By introducing new mechanisms for detecting failures and validating path integrity, this document enhances the operational robustness of P2MP Multicast deployments. Additionally, it ensures that existing MPLS and SR-based OAM tools can be effectively applied to networks utilizing SR P2MP Policies.

This document specifies the use of Topology Independent Loop-Free Alternate (TI-LFA) mechanisms with Multicast-only Fast Reroute (MoFRR) for Protocol Independent Multicast (PIM). The TI-LFA provides Fast Reroute (FRR) protection for unicast traffic in IP networks by precomputing backup paths that avoid potential failures. By integrating TI-LFA with MoFRR, this document extends the benefits of FRR mechanisms to multicast traffic, enabling enhanced resilience and minimized packet loss in multicast networks. The document outlines an optional approach to implement TI-LFA in conjunction with MoFRR for PIM, ensuring that multicast traffic is rapidly rerouted in the event of a failure.

This document specifies an update to the Receiver RLOC (Routing Locator) field of the PIM Join/Prune attribute that supports the construction of multicast distribution trees where the source and receivers are located in different Locator/ID Separation Protocol (LISP) sites and are connected using underlay IP multicast. This attribute allows the receiver site to signal the underlay multicast group to the control plane of the root Ingress Tunnel Router (ITR). This document updates RFC 8059.

The Internet Group Management Protocol (IGMP) is the protocol used by IPv4 systems to report their IP multicast group memberships to neighboring multicast routers. Version 3 of IGMP (IGMPv3) adds support for source filtering, that is, the ability for a system to report interest in receiving packets only from specific source addresses, or from all but specific source addresses, sent to a particular multicast address. That information may be used by multicast routing protocols to avoid delivering multicast packets from specific sources to networks where there are no interested receivers.

This document specifies IGMPv3. It is a revised version of RFC 3376 that includes clarifications and fixes for errata, and it is backward compatible with RFC 3376.

This document updates RFC 2236 and obsoletes RFC 3376.

This document specifies the Multicast Listener Discovery version 2 (MLDv2) protocol. MLD is used by an IPv6 router to discover the presence of multicast listeners on directly attached links and to discover which multicast addresses are of interest to those neighboring nodes. MLDv2 is designed to be interoperable with MLDv1. MLDv2 adds the ability for a node to report interest in listening to packets with a particular multicast address only from specific source addresses or from all sources except for specific source addresses.

This document updates RFC 2710 and obsoletes RFC 3810.

This document specifies revised IANA considerations for the Internet Group Management Protocol (IGMP) and the Multicast Listener Discovery (MLD) protocol. This document specifies the guidance provided to IANA to manage values associated with various fields within the protocol headers of the group management protocols.

This document obsoletes RFC 3228 and unifies guidelines for IPv4 and IPv6 group management protocols.

This document specifies Protocol Independent Multicast Light (PIM Light) and the PIM Light Interface (PLI). A PLI does not need a PIM Hello message to accept PIM Join/Prune messages, and it can signal multicast states over networks that cannot support full PIM neighbor discovery, such as Bit Index Explicit Replication (BIER) networks that connect two or more PIM domains. This document outlines the PIM Light protocol and procedures to ensure loop-free multicast traffic between two or more PIM Light routers.

As Internet audience sizes for high-interest live events reach unprecedented levels and bitrates climb to support formats and applications such as 4K, 8K, and Augmented Reality (AR), live streaming can place a unique type of stress upon network resources. TreeDN is a tree-based Content Delivery Network (CDN) architecture designed to address the distinctive scaling challenges of live streaming to mass audiences. TreeDN enables operators to offer Replication-as-a-Service (RaaS) at a fraction of the cost of traditional, unicast-based CDNs -- in some cases, at no additional cost to the infrastructure. In addition to efficiently utilizing network resources to deliver existing multi-destination traffic, this architecture also enables new types of content and use cases that previously were not possible or economically viable using traditional CDN approaches. Finally, TreeDN is a decentralized architecture and a democratizing technology that makes content distribution more accessible to more people by dramatically reducing the costs of replication.

When PIM Sparse Mode (PIM-SM), including PIM Source-Specific Multicast (PIM-SSM), is used in shared LAN networks, there is often more than one upstream router. This can lead to duplicate IP multicast packets being forwarded by these PIM routers. PIM Assert messages are used to elect a single forwarder for each IP multicast traffic flow between these routers.

This document defines a mechanism to send and receive information for multiple IP multicast flows in a single PackedAssert message. This optimization reduces the total number of PIM packets on the LAN and can therefore speed up the election of the single forwarder, reducing the number of duplicate IP multicast packets incurred.

In PIM Sparse Mode (PIM-SM) networks, PIM Null-Register messages are sent by the Designated Router (DR) to the Rendezvous Point (RP) to signal the presence of multicast sources in the network. There are periodic PIM Null-Registers sent from the DR to the RP to keep the state alive at the RP as long as the source is active. The PIM Null-Register message carries information about a single multicast source and group.

This document defines a standard to send information about multiple multicast sources and groups in a single PIM message. This document refers to the new messages as the "PIM Packed Null-Register message" and "PIM Packed Register-Stop message".

The PIM version 2 messages share a common message header format. The common header definition contains eight reserved bits. This document specifies how these bits may be used by individual message types and extends the PIM type space.

This document updates RFCs 7761 and 3973 by defining the use of the Reserved field in the PIM common header. This document further updates RFCs 7761 and 3973, along with RFCs 5015, 5059, 6754, and 8364, by specifying the use of the bits for each PIM message.

This document obsoletes RFC 8736.

This document defines a YANG data model that can be used to configure and manage Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) Proxy devices. The YANG module in this document conforms to the Network Management Datastore Architecture (NMDA).

This document defines a YANG data model that can be used to configure and manage devices supporting Protocol Independent Multicast (PIM). The model covers the PIM protocol configuration, operational state, and event notifications data.

This document specifies a generic mechanism to extend IGMPv3 and Multicast Listener Discovery Version 2 (MLDv2) by using a list of TLVs (Type, Length, and Value).

This document defines a YANG data model that can be used to configure and manage Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) snooping devices. The YANG module in this document conforms to the Network Management Datastore Architecture (NMDA).

This document defines a YANG data model for the configuration and management of Multicast Source Discovery Protocol (MSDP) protocol operations.

On a multi-access network, one of the PIM-SM (PIM Sparse Mode) routers is elected as a Designated Router. One of the responsibilities of the Designated Router is to track local multicast listeners and forward data to these listeners if the group is operating in PIM-SM. This document specifies a modification to the PIM-SM protocol that allows more than one of the PIM-SM routers to take on this responsibility so that the forwarding load can be distributed among multiple routers.

This document defines a YANG data model that can be used to configure and manage Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) devices.

This document describes the IP multicast traceroute facility, named Mtrace version 2 (Mtrace2). Unlike unicast traceroute, Mtrace2 requires special implementations on the part of routers. This specification describes the required functionality in multicast routers, as well as how an Mtrace2 client invokes a Query and receives a Reply.

Protocol Independent Multicast - Sparse Mode (PIM-SM) uses a Rendezvous Point (RP) and shared trees to forward multicast packets from new sources. Once Last-Hop Routers (LHRs) receive packets from a new source, they may join the Shortest Path Tree (SPT) for the source for optimal forwarding. This document defines a new mechanism that provides a way to support PIM-SM without the need for PIM registers, RPs, or shared trees. Multicast source information is flooded throughout the multicast domain using a new generic PIM Flooding Mechanism (PFM). This allows LHRs to learn about new sources without receiving initial data packets.

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.

This document describes the procedures and recommendations for Virtual Private LAN Service (VPLS) Provider Edges (PEs) to facilitate replication of multicast traffic to only certain ports (behind which there are interested Protocol Independent Multicast (PIM) routers and/or Internet Group Management Protocol (IGMP) hosts) via PIM snooping and proxying.

With PIM snooping, PEs passively listen to certain PIM control messages to build control and forwarding states while transparently flooding those messages. With PIM proxying, PEs do not flood PIM Join/Prune messages but only generate their own and send them out of certain ports, based on the control states built from downstream Join/Prune messages. PIM proxying is required when PIM Join suppression is enabled on the Customer Edge (CE) devices and is useful for reducing PIM control traffic in a VPLS domain.

This document also describes PIM relay, which can be viewed as lightweight proxying, where all downstream Join/Prune messages are simply forwarded out of certain ports and are not flooded, thereby avoiding the triggering of PIM Join suppression on CE devices.

This document specifies a solution for the delivery of IPv4 multicast services to IPv4 clients over an IPv6 multicast network. The solution relies upon a stateless IPv4-in-IPv6 encapsulation scheme and uses an IPv6 multicast distribution tree to deliver IPv4 multicast traffic. The solution is particularly useful for the delivery of multicast service offerings to customers serviced by Dual-Stack Lite (DS-Lite).

This document defines a Dynamic Host Configuration Protocol version 6 (DHCPv6) Option for multicast IPv4 service continuity solutions, which is used to carry the IPv6 prefixes to be used to build unicast and multicast IPv4-embedded IPv6 addresses.

This document defines two PIM Join/Prune attributes that support the construction of multicast distribution trees where the root and receivers are located in different Locator/ID Separation Protocol (LISP) sites. These attributes allow the receiver site to select between unicast and multicast underlying transport and to convey the RLOC (Routing Locator) address of the receiver ETR (Egress Tunnel Router) to the control plane of the root ITR (Ingress Tunnel Router).

This document describes procedures to damp Multicast VPN (MVPN) routing state changes and control the effect of the churn due to the multicast dynamicity in customer sites. The procedures described in this document are applicable to BGP-based multicast VPN and help avoid uncontrolled control-plane load increase in the core routing infrastructure. The new procedures proposed were inspired by BGP unicast route damping principles that have been adapted to multicast.

This document introduces VRRP-aware PIM, a redundancy mechanism for the Protocol Independent Multicast (PIM) to interoperate with the Virtual Router Redundancy Protocol (VRRP). It allows PIM to track VRRP state and to preserve multicast traffic upon failover in a redundant network with virtual routing groups enabled. The mechanism described in this document is based on Cisco IOS software implementation.

The PIM Reverse Path Forwarding (RPF) Vector TLV defined in RFC 5496 can be included in a PIM Join Attribute such that the RPF neighbor is selected based on the unicast reachability of the RPF Vector instead of the source or Rendezvous Point associated with the multicast tree.

This document defines a new RPF Vector Attribute type such that an explicit RPF neighbor list can be encoded in the PIM Join Attribute, thus bypassing the unicast route lookup.

This document defines a hierarchical method of encoding Join/Prune attributes that provides a more efficient encoding when the same attribute values need to be specified for multiple sources in a PIM Join/Prune message. This document updates RFC 5384 by renaming the encoding type registry specified there.

Fast handover protocols for Mobile IPv6 (MIPv6) and Proxy Mobile IPv6 (PMIPv6) define mobility management procedures that support unicast communication at reduced handover latency. Fast handover base operations do not affect multicast communication and, hence, do not accelerate handover management for native multicast listeners. Many multicast applications like IPTV or conferencing, though, comprise delay-sensitive, real-time traffic and will benefit from fast handover completion. This document specifies extension of the Mobile IPv6 Fast Handovers (FMIPv6) and the Fast Handovers for Proxy Mobile IPv6 (PFMIPv6) protocols to include multicast traffic management in fast handover operations. This multicast support is provided first at the control plane by management of rapid context transfer between access routers and second at the data plane by optional fast traffic forwarding that may include buffering. An FMIPv6 access router indicates support for multicast using an updated Proxy Router Advertisements message format.

This document updates RFC 5568, "Mobile IPv6 Fast Handovers".

This specification defines "jCard", a JSON format for vCard data. The vCard data format is a text format for representing and exchanging information about individuals and other entities, for example, telephone numbers, email addresses, structured names, and delivery addresses. JSON is a lightweight, text-based, language- independent data interchange format commonly used in Internet applications.

This specification defines a method for providing multicast distribution-tree accounting data. Simple extensions to the Protocol Independent Multicast (PIM) protocol allow a rough approximation of tree-based data in a scalable fashion. This document defines an Experimental Protocol for the Internet community.

A Protocol Independent Multicast (PIM) router uses the Reverse Path Forwarding (RPF) procedure to select an upstream interface and router in order to build forwarding state. When there are equal cost multipaths (ECMPs), existing implementations often use hash algorithms to select a path. Such algorithms do not allow the spread of traffic among the ECMPs according to administrative metrics. This usually leads to inefficient or ineffective use of network resources. This document introduces the ECMP Redirect, a mechanism to improve the RPF procedure over ECMPs. It allows ECMP selection to be based on administratively selected metrics, such as data transmission delays, path preferences, and routing metrics. [STANDARDS-TRACK]

This document defines a reliable transport mechanism for the PIM protocol for transmission of Join/Prune messages. This eliminates the need for periodic Join/Prune message transmission and processing. The reliable transport mechanism can use either TCP or SCTP as the transport protocol. This document defines an Experimental Protocol for the Internet community.

The specification for Multicast Virtual Private Networks (MVPNs) contains an option that allows the use of PIM as the control protocol between provider edge routers. It also contains an option that allows UDP-based messages, known as Selective Provider Multicast Service Interface (S-PMSI) Join messages, to be used to bind particular customer multicast flows to particular tunnels through a service provider's network. This document extends the MVPN specification (RFC 6513) so that these options can be used when the customer multicast flows are IPv6 flows. [STANDARDS-TRACK]

More that one set of mechanisms to support multicast in a layer 3 BGP/MPLS VPN has been defined. These are presented in the documents that define them as optional building blocks.

To enable interoperability between implementations, this document defines a subset of features that is considered mandatory for a multicast BGP/MPLS VPN implementation. This will help implementers and deployers understand which L3VPN multicast requirements are best satisfied by each option. This document is not an Internet Standards Track specification; it is published for informational purposes.

This document introduces a new type of PIM Join Attribute that extends PIM signaling to identify a topology that should be used when constructing a particular multicast distribution tree. [STANDARDS-TRACK]

This document defines a new PIM Hello option to advertise an Interface Identifier that can be used by PIM protocols to uniquely identify an interface of a neighboring router. [STANDARDS-TRACK]

Each Protocol Independent Multicast - Sparse Mode (PIM-SM) router in a PIM domain that supports Any Source Multicast (ASM) maintains Group-to-RP mappings that are used to identify a Rendezvous Point (RP) for a specific multicast group. PIM-SM has defined an algorithm to choose a RP from the Group-to-RP mappings learned using various mechanisms. This algorithm does not consider the PIM mode and the mechanism through which a Group-to-RP mapping was learned.

This document defines a standard algorithm to deterministically choose between several Group-to-RP mappings for a specific group. This document first explains the requirements to extend the Group-to-RP mapping algorithm and then proposes the new algorithm. [STANDARDS-TRACK]

This document describes a use of the Protocol Independent Multicast (PIM) Join Attribute as defined in RFC 5384, which enables PIM to build multicast trees through an MPLS-enabled network, even if that network's IGP does not have a route to the source of the tree. [STANDARDS-TRACK]

This document provides functional requirements for network solutions that support multicast over Virtual Private LAN Service (VPLS). It specifies requirements both from the end user and service provider standpoints. It is intended that potential solutions will use these requirements as guidelines. This memo provides information for the Internet community.

This memo complements the list of multicast infrastructure security threat analysis documents by describing Protocol Independent Multicast (PIM) threats specific to router interfaces connecting hosts. This memo provides information for the Internet community.

This document defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used for managing the Bootstrap Router (BSR) mechanism for PIM (Protocol Independent Multicast). [STANDARDS-TRACK]

This document specifies the Bootstrap Router (BSR) mechanism for the class of multicast routing protocols in the PIM (Protocol Independent Multicast) family that use the concept of a Rendezvous Point as a means for receivers to discover the sources that send to a particular multicast group. BSR is one way that a multicast router can learn the set of group-to-RP mappings required in order to function. The mechanism is dynamic, largely self-configuring, and robust to router failure. [STANDARDS-TRACK]

This document discusses Bidirectional PIM (BIDIR-PIM), a variant of PIM Sparse-Mode that builds bidirectional shared trees connecting multicast sources and receivers. Bidirectional trees are built using a fail-safe Designated Forwarder (DF) election mechanism operating on each link of a multicast topology. With the assistance of the DF, multicast data is natively forwarded from sources to the Rendezvous-Point (RP) and hence along the shared tree to receivers without requiring source-specific state. The DF election takes place at RP discovery time and provides the route to the RP, thus eliminating the requirement for data-driven protocol events. [STANDARDS-TRACK]

IP Multicast group addresses in the 232/8 (232.0.0.0 to 232.255.255.255) range are designated as source-specific multicast destination addresses and are reserved for use by source-specific multicast applications and protocols. This document defines operational recommendations to ensure source-specific behavior within the 232/8 range. 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 document specifies Protocol Independent Multicast - Dense Mode (PIM-DM). PIM-DM is a multicast routing protocol that uses the underlying unicast routing information base to flood multicast datagrams to all multicast routers. Prune messages are used to prevent future messages from propagating to routers without group membership information. This memo defines an Experimental Protocol for the Internet community.

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 memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used for managing the Protocol Independent Multicast (PIM) protocol for IPv4. This memo defines an Experimental Protocol for the Internet community.

This document describes how intra-LIS IP multicast can be efficiently supported among routers over ATM without using the Multicast Address Resolution Server (MARS). This memo defines an Experimental Protocol for the Internet community. It does not specify an Internet standard of any kind. Discussion and suggestions for improvement are requested.