RFC Abstracts

RFC6562 - Guidelines for the Use of Variable Bit Rate Audio with Secure RTP
This memo discusses potential security issues that arise when using variable bit rate (VBR) audio with the secure RTP profile. Guidelines to mitigate these issues are suggested. [STANDARDS-TRACK]
RFC6561 - Recommendations for the Remediation of Bots in ISP Networks
This document contains recommendations on how Internet Service Providers can use various remediation techniques to manage the effects of malicious bot infestations on computers used by their subscribers. Internet users with infected computers are exposed to risks such as loss of personal data and increased susceptibility to online fraud. Such computers can also become inadvertent participants in or components of an online crime network, spam network, and/or phishing network as well as be used as a part of a distributed denial-of-service attack. Mitigating the effects of and remediating the installations of malicious bots will make it more difficult for botnets to operate and could reduce the level of online crime on the Internet in general and/or on a particular Internet Service Provider's network. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6560 - One-Time Password (OTP) Pre-Authentication
The Kerberos protocol provides a framework authenticating a client using the exchange of pre-authentication data. This document describes the use of this framework to carry out One-Time Password (OTP) authentication. [STANDARDS-TRACK]
RFC6559 - A Reliable Transport Mechanism for PIM
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.
RFC6558 - Sieve Extension for Converting Messages before Delivery
This document describes how the "CONVERT" IMAP extension can be used within the Sieve mail filtering language to transform messages before final delivery. [STANDARDS-TRACK]
RFC6557 - Procedures for Maintaining the Time Zone Database
Time zone information serves as a basic protocol element in protocols, such as the calendaring suite and DHCP. The Time Zone (TZ) Database specifies the indices used in various protocols, as well as their semantic meanings, for all localities throughout the world. This database has been meticulously maintained and distributed free of charge by a group of volunteers, coordinated by a single volunteer who is now planning to retire. This memo specifies procedures involved with maintenance of the TZ database and associated code, including how to submit proposed updates, how decisions for inclusion of those updates are made, and the selection of a designated expert by and for the time zone community. The intent of this memo is, to the extent possible, to document existing practice and provide a means to ease succession of the database maintainers. This memo documents an Internet Best Current Practice.
RFC6556 - Testing Eyeball Happiness
The amount of time it takes to establish a session using common transport APIs in dual-stack networks and networks with filtering such as proposed in BCP 38 is a barrier to IPv6 deployment. This note describes a test that can be used to determine whether an application can reliably establish sessions quickly in a complex environment such as dual-stack (IPv4+IPv6) deployment or IPv6 deployment with multiple prefixes and upstream ingress filtering. This test is not a test of a specific algorithm, but of the external behavior of the system as a black box. Any algorithm that has the intended external behavior will be accepted by it. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6555 - Happy Eyeballs: Success with Dual-Stack Hosts
When a server's IPv4 path and protocol are working, but the server's IPv6 path and protocol are not working, a dual-stack client application experiences significant connection delay compared to an IPv4-only client. This is undesirable because it causes the dual- stack client to have a worse user experience. This document specifies requirements for algorithms that reduce this user-visible delay and provides an algorithm. [STANDARDS-TRACK]
RFC6554 - An IPv6 Routing Header for Source Routes with the Routing Protocol for Low-Power and Lossy Networks (RPL)
In Low-Power and Lossy Networks (LLNs), memory constraints on routers may limit them to maintaining, at most, a few routes. In some configurations, it is necessary to use these memory-constrained routers to deliver datagrams to nodes within the LLN. The Routing Protocol for Low-Power and Lossy Networks (RPL) can be used in some deployments to store most, if not all, routes on one (e.g., the Directed Acyclic Graph (DAG) root) or a few routers and forward the IPv6 datagram using a source routing technique to avoid large routing tables on memory-constrained routers. This document specifies a new IPv6 Routing header type for delivering datagrams within a RPL routing domain. [STANDARDS-TRACK]
RFC6553 - The Routing Protocol for Low-Power and Lossy Networks (RPL) Option for Carrying RPL Information in Data-Plane Datagrams
The Routing Protocol for Low-Power and Lossy Networks (RPL) includes routing information in data-plane datagrams to quickly identify inconsistencies in the routing topology. This document describes the RPL Option for use among RPL routers to include such routing information. [STANDARDS-TRACK]
RFC6552 - Objective Function Zero for the Routing Protocol for Low-Power and Lossy Networks (RPL)
The Routing Protocol for Low-Power and Lossy Networks (RPL) specification defines a generic Distance Vector protocol that is adapted to a variety of network types by the application of specific Objective Functions (OFs). An OF states the outcome of the process used by a RPL node to select and optimize routes within a RPL Instance based on the Information Objects available; an OF is not an algorithm.
RFC6551 - Routing Metrics Used for Path Calculation in Low-Power and Lossy Networks
Low-Power and Lossy Networks (LLNs) have unique characteristics compared with traditional wired and ad hoc networks that require the specification of new routing metrics and constraints. By contrast, with typical Interior Gateway Protocol (IGP) routing metrics using hop counts or link metrics, this document specifies a set of link and node routing metrics and constraints suitable to LLNs to be used by the Routing Protocol for Low-Power and Lossy Networks (RPL). [STANDARDS-TRACK]
RFC6550 - RPL: IPv6 Routing Protocol for Low-Power and Lossy Networks
Low-Power and Lossy Networks (LLNs) are a class of network in which both the routers and their interconnect are constrained. LLN routers typically operate with constraints on processing power, memory, and energy (battery power). Their interconnects are characterized by high loss rates, low data rates, and instability. LLNs are comprised of anything from a few dozen to thousands of routers. Supported traffic flows include point-to-point (between devices inside the LLN), point-to-multipoint (from a central control point to a subset of devices inside the LLN), and multipoint-to-point (from devices inside the LLN towards a central control point). This document specifies the IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL), which provides a mechanism whereby multipoint-to-point traffic from devices inside the LLN towards a central control point as well as point-to-multipoint traffic from the central control point to the devices inside the LLN are supported. Support for point-to-point traffic is also available. [STANDARDS-TRACK]
RFC6549 - OSPFv2 Multi-Instance Extensions
OSPFv3 includes a mechanism to support multiple instances of the protocol running on the same interface. OSPFv2 can utilize such a mechanism in order to support multiple routing domains on the same subnet.
RFC6548 - Independent Submission Editor Model
This document describes the function and responsibilities of the RFC Independent Submission Editor (ISE). The Independent Submission stream is one of the stream producers that create draft RFCs, with the ISE as its stream approver. The ISE is overall responsible for activities within the Independent Submission stream, working with draft editors and reviewers, and interacts with the RFC Production Center and Publisher, and the RFC Series Editor (RSE). The ISE is appointed by the IAB, and also interacts with the IETF Administrative Oversight Committee (IAOC). This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6547 - RFC 3627 to Historic Status
This document moves "Use of /127 Prefix Length Between Routers Considered Harmful" (RFC 3627) to Historic status to reflect the updated guidance contained in "Using 127-Bit IPv6 Prefixes on Inter- Router Links" (RFC 6164). A Standards Track document supersedes an informational document; therefore, guidance provided in RFC 6164 is to be followed when the two documents are in conflict. This document links the two RFCs so that the IETF's updated guidance on this topic is clearer. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6546 - Transport of Real-time Inter-network Defense (RID) Messages over HTTP/TLS
The Incident Object Description Exchange Format (IODEF) defines a common XML format for document exchange, and Real-time Inter-network Defense (RID) defines extensions to IODEF intended for the cooperative handling of security incidents within consortia of network operators and enterprises. This document specifies an application-layer protocol for RID based upon the passing of RID messages over HTTP/TLS. [STANDARDS-TRACK]
RFC6545 - Real-time Inter-network Defense (RID)
Security incidents, such as system compromises, worms, viruses, phishing incidents, and denial of service, typically result in the loss of service, data, and resources both human and system. Service providers and Computer Security Incident Response Teams need to be equipped and ready to assist in communicating and tracing security incidents with tools and procedures in place before the occurrence of an attack. Real-time Inter-network Defense (RID) outlines a proactive inter-network communication method to facilitate sharing incident-handling data while integrating existing detection, tracing, source identification, and mitigation mechanisms for a complete incident-handling solution. Combining these capabilities in a communication system provides a way to achieve higher security levels on networks. Policy guidelines for handling incidents are recommended and can be agreed upon by a consortium using the security recommendations and considerations. This document obsoletes RFC 6045. [STANDARDS-TRACK]
RFC6544 - TCP Candidates with Interactive Connectivity Establishment (ICE)
Interactive Connectivity Establishment (ICE) defines a mechanism for NAT traversal for multimedia communication protocols based on the offer/answer model of session negotiation. ICE works by providing a set of candidate transport addresses for each media stream, which are then validated with peer-to-peer connectivity checks based on Session Traversal Utilities for NAT (STUN). ICE provides a general framework for describing candidates but only defines UDP-based media streams. This specification extends ICE to TCP-based media, including the ability to offer a mix of TCP and UDP-based candidates for a single stream. [STANDARDS-TRACK]
RFC6543 - Reserved IPv6 Interface Identifier for Proxy Mobile IPv6
Proxy Mobile IPv6 (RFC 5213) requires that all mobile access gateways use a fixed link-local address and a fixed link-layer address on any of their access links that they share with mobile nodes. This requirement was intended to ensure that a mobile node does not detect any change with respect to its Layer 3 attachment, even after it roams from one mobile access gateway to another. In the absence of any reserved addresses for this use, coordination across vendors and manual configuration of these addresses on all of the mobility elements in a Proxy Mobile IPv6 domain are required. This document attempts to simplify this operational requirement by making a reservation for special addresses that can be used for this purpose. This document also updates RFC 5213. [STANDARDS-TRACK]
RFC6542 - Kerberos Version 5 Generic Security Service Application Program Interface (GSS-API) Channel Binding Hash Agility
Currently, channel bindings are implemented using an MD5 hash in the Kerberos Version 5 Generic Security Service Application Programming Interface (GSS-API) mechanism (RFC 4121). This document updates RFC 4121 to allow channel bindings using algorithms negotiated based on Kerberos crypto framework as defined in RFC 3961. In addition, because this update makes use of the last extensible field in the Kerberos client-server exchange message, extensions are defined to allow future protocol extensions. [STANDARDS-TRACK]
RFC6541 - DomainKeys Identified Mail (DKIM) Authorized Third-Party Signatures
This experimental specification proposes a modification to DomainKeys Identified Mail (DKIM) allowing advertisement of third-party signature authorizations that are to be interpreted as equivalent to a signature added by the administrative domain of the message's author. This document defines an Experimental Protocol for the Internet community.
RFC6540 - IPv6 Support Required for All IP-Capable Nodes
Given the global lack of available IPv4 space, and limitations in IPv4 extension and transition technologies, this document advises that IPv6 support is no longer considered optional. It also cautions that there are places in existing IETF documents where the term "IP" is used in a way that could be misunderstood by implementers as the term "IP" becomes a generic that can mean IPv4 + IPv6, IPv6-only, or IPv4-only, depending on context and application. This memo documents an Internet Best Current Practice.
RFC6539 - IBAKE: Identity-Based Authenticated Key Exchange
Cryptographic protocols based on public-key methods have been traditionally based on certificates and Public Key Infrastructure (PKI) to support certificate management. The emerging field of Identity-Based Encryption (IBE) protocols allows simplification of infrastructure requirements via a Private-Key Generator (PKG) while providing the same flexibility. However, one significant limitation of IBE methods is that the PKG can end up being a de facto key escrow server, with undesirable consequences. Another observed deficiency is a lack of mutual authentication of communicating parties. This document specifies the Identity-Based Authenticated Key Exchange (IBAKE) protocol. IBAKE does not suffer from the key escrow problem and in addition provides mutual authentication as well as perfect forward and backward secrecy. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6538 - The Host Identity Protocol (HIP) Experiment Report
This document is a report from the IRTF Host Identity Protocol (HIP) research group documenting the collective experiences and lessons learned from studies, related experimentation, and designs completed by the research group. The document summarizes implications of adding HIP to host protocol stacks, Internet infrastructure, and applications. The perspective of a network operator, as well as a list of HIP experiments, are presented as well. Portions of this report may be relevant also to other network overlay-based architectures or to attempts to deploy alternative networking architectures. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6537 - Host Identity Protocol Distributed Hash Table Interface
This document specifies a common interface for using the Host Identity Protocol (HIP) with a Distributed Hash Table (DHT) service to provide a name-to-Host-Identity-Tag lookup service and a Host- Identity-Tag-to-address lookup service. This document defines an Experimental Protocol for the Internet community.
RFC6536 - Network Configuration Protocol (NETCONF) Access Control Model
The standardization of network configuration interfaces for use with the Network Configuration Protocol (NETCONF) requires a structured and secure operating environment that promotes human usability and multi-vendor interoperability. There is a need for standard mechanisms to restrict NETCONF protocol access for particular users to a pre-configured subset of all available NETCONF protocol operations and content. This document defines such an access control model. [STANDARDS-TRACK]
RFC6535 - Dual-Stack Hosts Using "Bump-in-the-Host" (BIH)
Bump-in-the-Host (BIH) is a host-based IPv4 to IPv6 protocol translation mechanism that allows a class of IPv4-only applications that work through NATs to communicate with IPv6-only peers. The host on which applications are running may be connected to IPv6-only or dual-stack access networks. BIH hides IPv6 and makes the IPv4-only applications think they are talking with IPv4 peers by local synthesis of IPv4 addresses. This document obsoletes RFC 2767 and RFC 3338. [STANDARDS-TRACK]
RFC6534 - Loss Episode Metrics for IP Performance Metrics (IPPM)
The IETF has developed a one-way packet loss metric that measures the loss rate on a Poisson and Periodic probe streams between two hosts. However, the impact of packet loss on applications is, in general, sensitive not just to the average loss rate but also to the way in which packet losses are distributed in loss episodes (i.e., maximal sets of consecutively lost probe packets). This document defines one-way packet loss episode metrics, specifically, the frequency and average duration of loss episodes and a probing methodology under which the loss episode metrics are to be measured. [STANDARDS-TRACK]
RFC6533 - Internationalized Delivery Status and Disposition Notifications
Delivery status notifications (DSNs) are critical to the correct operation of an email system. However, the existing Draft Standards (RFC 3461, RFC 3464, RFC 6522) are presently limited to ASCII text in the machine-readable portions of the protocol. This specification adds a new address type for international email addresses so an original recipient address with non-ASCII characters can be correctly preserved even after downgrading. This also provides updated content return media types for delivery status notifications and message disposition notifications to support use of the new address type.
RFC6532 - Internationalized Email Headers
Internet mail was originally limited to 7-bit ASCII. MIME added support for the use of 8-bit character sets in body parts, and also defined an encoded-word construct so other character sets could be used in certain header field values. However, full internationalization of electronic mail requires additional enhancements to allow the use of Unicode, including characters outside the ASCII repertoire, in mail addresses as well as direct use of Unicode in header fields like "From:", "To:", and "Subject:", without requiring the use of complex encoded-word constructs. This document specifies an enhancement to the Internet Message Format and to MIME that allows use of Unicode in mail addresses and most header field content.
RFC6531 - SMTP Extension for Internationalized Email
This document specifies an SMTP extension for transport and delivery of email messages with internationalized email addresses or header information. [STANDARDS-TRACK]
RFC6530 - Overview and Framework for Internationalized Email
Full use of electronic mail throughout the world requires that (subject to other constraints) people be able to use close variations on their own names (written correctly in their own languages and scripts) as mailbox names in email addresses. This document introduces a series of specifications that define mechanisms and protocol extensions needed to fully support internationalized email addresses. These changes include an SMTP extension and extension of email header syntax to accommodate UTF-8 data. The document set also includes discussion of key assumptions and issues in deploying fully internationalized email. This document is a replacement for RFC 4952; it reflects additional issues identified since that document was published. [STANDARDS-TRACK]
RFC6529 - Host/Host Protocol for the ARPA Network
This document reproduces the Host/Host Protocol developed by the ARPA Network Working Group during 1969, 1970, and 1971. It describes a protocol used to manage communication between processes residing on independent Hosts. It addresses issues of multiplexing multiple streams of communication (including addressing, flow control, connection establishment/disestablishment, and other signaling) over a single hardware interface. It was the official protocol of the ARPA Network from January 1972 until the switch to TCP/IP in January 1983. It is offered as an RFC at this late date to help complete the historical record available through the RFC series. This document is not an Internet Standards Track specification; it is published for the historical record.
RFC6528 - Defending against Sequence Number Attacks
This document specifies an algorithm for the generation of TCP Initial Sequence Numbers (ISNs), such that the chances of an off-path attacker guessing the sequence numbers in use by a target connection are reduced. This document revises (and formally obsoletes) RFC 1948, and takes the ISN generation algorithm originally proposed in that document to Standards Track, formally updating RFC 793. [STANDARDS-TRACK]
RFC6527 - Definitions of Managed Objects for Virtual Router Redundancy Protocol Version 3 (VRRPv3)
This specification defines a portion of the Management Information Base (MIB) for use with network management based on the Simple Network Management Protocol (SNMP). In particular, it defines objects for configuring, monitoring, and controlling routers that employ the Virtual Router Redundancy Protocol Version 3 (VRRPv3) for both IPv4 and IPv6 as defined in RFC 5798. This memo obsoletes RFC 2787. [STANDARDS-TRACK]
RFC6526 - IP Flow Information Export (IPFIX) Per Stream Control Transmission Protocol (SCTP) Stream
This document specifies an extension to the specifications in RFC 5101, IP Flow Information Export (IPFIX), when using the Partial Reliability extension of SCTP (PR-SCTP, Partial Reliability Stream Control Transmission Protocol).
RFC6525 - Stream Control Transmission Protocol (SCTP) Stream Reconfiguration
Many applications that use the Stream Control Transmission Protocol (SCTP) want the ability to "reset" a stream. The intention of resetting a stream is to set the numbering sequence of the stream back to 'zero' with a corresponding notification to the application layer that the reset has been performed. Applications requiring this feature want it so that they can "reuse" streams for different purposes but still utilize the stream sequence number so that the application can track the message flows. Thus, without this feature, a new use of an old stream would result in message numbers greater than expected, unless there is a protocol mechanism to "reset the streams back to zero". This document also includes methods for resetting the transmission sequence numbers, adding additional streams, and resetting all stream sequence numbers. [STANDARDS-TRACK]
RFC6522 - The Multipart/Report Media Type for the Reporting of Mail System Administrative Messages
The multipart/report Multipurpose Internet Mail Extensions (MIME) media type is a general "family" or "container" type for electronic mail reports of any kind. Although this memo defines only the use of the multipart/report media type with respect to delivery status reports, mail processing programs will benefit if a single media type is used for all kinds of reports.
RFC6521 - Home Agent-Assisted Route Optimization between Mobile IPv4 Networks
This document describes a home agent-assisted route optimization functionality for the IPv4 Network Mobility Protocol. The function is designed to facilitate optimal routing in cases where all nodes are connected to a single home agent; thus, the use case is route optimization within a single organization or similar entity. The functionality enables the discovery of eligible peer nodes (based on information received from the home agent) and their network prefixes, and the establishment of a direct tunnel between such nodes. This document defines an Experimental Protocol for the Internet community.
RFC6520 - Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS) Heartbeat Extension
This document describes the Heartbeat Extension for the Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS) protocols.
RFC6519 - RADIUS Extensions for Dual-Stack Lite
Dual-Stack Lite is a solution to offer both IPv4 and IPv6 connectivity to customers that are addressed only with an IPv6 prefix. Dual-Stack Lite requires pre-configuration of the Dual-Stack Lite Address Family Transition Router (AFTR) tunnel information on the Basic Bridging BroadBand (B4) element. In many networks, the customer profile information may be stored in Authentication, Authorization, and Accounting (AAA) servers, while client configurations are mainly provided through the Dynamic Host Configuration Protocol (DHCP). This document specifies a new Remote Authentication Dial-In User Service (RADIUS) attribute to carry the Dual-Stack Lite AFTR tunnel name; the RADIUS attribute is defined based on the equivalent DHCPv6 OPTION_AFTR_NAME option. This RADIUS attribute is meant to be used between the RADIUS server and the Network Access Server (NAS); it is not intended to be used directly between the B4 element and the RADIUS server. [STANDARDS-TRACK]
RFC6518 - Keying and Authentication for Routing Protocols (KARP) Design Guidelines
This document is one of a series concerned with defining a roadmap of protocol specification work for the use of modern cryptographic mechanisms and algorithms for message authentication in routing protocols. In particular, it defines the framework for a key management protocol that may be used to create and manage session keys for message authentication and integrity. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6517 - Mandatory Features in a Layer 3 Multicast BGP/MPLS VPN Solution
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.
RFC6516 - IPv6 Multicast VPN (MVPN) Support Using PIM Control Plane and Selective Provider Multicast Service Interface (S-PMSI) Join Messages
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]
RFC6515 - IPv4 and IPv6 Infrastructure Addresses in BGP Updates for Multicast VPN
To provide Multicast VPN (MVPN) service, Provider Edge routers originate BGP Update messages that carry Multicast-VPN ("MCAST-VPN") BGP routes; they also originate unicast VPN routes that carry MVPN-specific attributes. These routes encode addresses from the customer's address space, as well as addresses from the provider's address space. These two address spaces are independent, and the address family (IPv4 or IPv6) of the two spaces may or may not be the same. These routes always contain an "address family" field that specifies whether the customer addresses are IPv4 addresses or whether they are IPv6 addresses. However, there is no field that explicitly specifies the address family of the provider addresses. To ensure interoperability, this document specifies that provider IPv4 addresses are always encoded in these update messages as 4-octet addresses, and that the distinction between IPv4 and IPv6 is signaled solely by the length of the address field. Specific cases are explained in detail. This document updates RFC 6514. [STANDARDS-TRACK]
RFC6514 - BGP Encodings and Procedures for Multicast in MPLS/BGP IP VPNs
This document describes the BGP encodings and procedures for exchanging the information elements required by Multicast in MPLS/BGP IP VPNs, as specified in RFC 6513. [STANDARDS-TRACK]
RFC6513 - Multicast in MPLS/BGP IP VPNs
In order for IP multicast traffic within a BGP/MPLS IP VPN (Virtual Private Network) to travel from one VPN site to another, special protocols and procedures must be implemented by the VPN Service Provider. These protocols and procedures are specified in this document. [STANDARDS-TRACK]
RFC6512 - Using Multipoint LDP When the Backbone Has No Route to the Root
The control protocol used for constructing Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths ("MP LSPs") contains a field that identifies the address of a "root node". Intermediate nodes are expected to be able to look up that address in their routing tables. However, this is not possible if the route to the root node is a BGP route and the intermediate nodes are part of a BGP-free core. This document specifies procedures that enable an MP LSP to be constructed through a BGP-free core. In these procedures, the root node address is temporarily replaced by an address that is known to the intermediate nodes and is on the path to the true root node. [STANDARDS-TRACK]
RFC6511 - Non-Penultimate Hop Popping Behavior and Out-of-Band Mapping for RSVP-TE Label Switched Paths
There are many deployment scenarios that require an egress Label Switching Router (LSR) to receive binding of the Resource Reservation Protocol - Traffic Engineering (RSVP-TE) Label Switched Path (LSP) to an application and a payload identifier using some "out-of-band" (OOB) mechanism. This document defines protocol mechanisms to address this requirement. The procedures described in this document are equally applicable for point-to-point (P2P) and point-to-multipoint (P2MP) LSPs. [STANDARDS-TRACK]