Tsvwg Workgroup RFCs

Browse Tsvwg Workgroup RFCs by Number

RFC2861 - TCP Congestion Window Validation: This document describes a simple modification to TCP's congestion control algorithms to decay the congestion window cwnd after the transition from a sufficiently-long application-limited period, while using the slow-start threshold ssthresh to save information about the previous value of the congestion window. This memo defines an Experimental Protocol for the Internet community.
RFC2883 - An Extension to the Selective Acknowledgement (SACK) Option for TCP: This note defines an extension of the Selective Acknowledgement (SACK) Option for TCP. [STANDARDS-TRACK]
RFC2988 - Computing TCP's Retransmission Timer: This document defines the standard algorithm that Transmission Control Protocol (TCP) senders are required to use to compute and manage their retransmission timer. [STANDARDS-TRACK]
RFC3042 - Enhancing TCP's Loss Recovery Using Limited Transmit: This document proposes a new Transmission Control Protocol (TCP) mechanism that can be used to more effectively recover lost segments when a connection's congestion window is small, or when a large number of segments are lost in a single transmission window. [STANDARDS-TRACK]
RFC3168 - The Addition of Explicit Congestion Notification (ECN) to IP: This memo specifies the incorporation of ECN (Explicit Congestion Notification) to TCP and IP, including ECN's use of two bits in the IP header. [STANDARDS-TRACK]
RFC3309 - Stream Control Transmission Protocol (SCTP) Checksum Change
RFC3390 - Increasing TCP's Initial Window
RFC3436 - Transport Layer Security over Stream Control Transmission Protocol: This document describes the usage of the Transport Layer Security (TLS) protocol, as defined in RFC 2246, over the Stream Control Transmission Protocol (SCTP), as defined in RFC 2960 and RFC 3309. The user of TLS can take advantage of the features provided by SCTP, namely the support of multiple streams to avoid head of line blocking and the support of multi-homing to provide network level fault tolerance. Additionally, discussions of extensions of SCTP are also supported, meaning especially the support of dynamic reconfiguration of IP- addresses. [STANDARDS-TRACK]
RFC3448 - TCP Friendly Rate Control (TFRC): Protocol Specification: This document specifies TCP-Friendly Rate Control (TFRC). TFRC is a congestion control mechanism for unicast flows operating in a best- effort Internet environment. It is reasonably fair when competing for bandwidth with TCP flows, but has a much lower variation of throughput over time compared with TCP, making it more suitable for applications such as telephony or streaming media where a relatively smooth sending rate is of importance. [STANDARDS-TRACK]
RFC3517 - A Conservative Selective Acknowledgment (SACK)-based Loss Recovery Algorithm for TCP: This document presents a conservative loss recovery algorithm for TCP that is based on the use of the selective acknowledgment (SACK) TCP option. The algorithm presented in this document conforms to the spirit of the current congestion control specification (RFC 2581), but allows TCP senders to recover more effectively when multiple segments are lost from a single flight of data. [STANDARDS-TRACK]
RFC3522 - The Eifel Detection Algorithm for TCP: The Eifel detection algorithm allows a TCP sender to detect a posteriori whether it has entered loss recovery unnecessarily. It requires that the TCP Timestamps option defined in RFC 1323 be enabled for a connection. The Eifel detection algorithm makes use of the fact that the TCP Timestamps option eliminates the retransmission ambiguity in TCP. Based on the timestamp of the first acceptable ACK that arrives during loss recovery, it decides whether loss recovery was entered unnecessarily. The Eifel detection algorithm provides a basis for future TCP enhancements. This includes response algorithms to back out of loss recovery by restoring a TCP sender's congestion control state. This memo defines an Experimental Protocol for the Internet community.
RFC3540 - Robust Explicit Congestion Notification (ECN) Signaling with Nonces: This note describes the Explicit Congestion Notification (ECN)-nonce, an optional addition to ECN that protects against accidental or malicious concealment of marked packets from the TCP sender. It improves the robustness of congestion control by preventing receivers from exploiting ECN to gain an unfair share of network bandwidth. The ECN-nonce uses the two ECN-Capable Transport (ECT)codepoints in the ECN field of the IP header, and requires a flag in the TCP header. It is computationally efficient for both routers and hosts. This memo defines an Experimental Protocol for the Internet community.
RFC3649 - HighSpeed TCP for Large Congestion Windows: The proposals in this document are experimental. While they may be deployed in the current Internet, they do not represent a consensus that this is the best method for high-speed congestion control. In particular, we note that alternative experimental proposals are likely to be forthcoming, and it is not well understood how the proposals in this document will interact with such alternative proposals. This document proposes HighSpeed TCP, a modification to TCP's congestion control mechanism for use with TCP connections with large congestion windows. The congestion control mechanisms of the current Standard TCP constrains the congestion windows that can be achieved by TCP in realistic environments. For example, for a Standard TCP connection with 1500-byte packets and a 100 ms round-trip time, achieving a steady-state throughput of 10 Gbps would require an average congestion window of 83,333 segments, and a packet drop rate of at most one congestion event every 5,000,000,000 packets (or equivalently, at most one congestion event every 1 2/3 hours). This is widely acknowledged as an unrealistic constraint. To address his limitation of TCP, this document proposes HighSpeed TCP, and solicits experimentation and feedback from the wider community.
RFC3708 - Using TCP Duplicate Selective Acknowledgement (DSACKs) and Stream Control Transmission Protocol (SCTP) Duplicate Transmission Sequence Numbers (TSNs) to Detect Spurious Retransmissions: TCP and Stream Control Transmission Protocol (SCTP) provide notification of duplicate segment receipt through Duplicate Selective Acknowledgement (DSACKs) and Duplicate Transmission Sequence Number (TSN) notification, respectively. This document presents conservative methods of using this information to identify unnecessary retransmissions for various applications. This memo defines an Experimental Protocol for the Internet community.
RFC3742 - Limited Slow-Start for TCP with Large Congestion Windows: This document describes an optional modification for TCP's slow-start for use with TCP connections with large congestion windows. For TCP connections that are able to use congestion windows of thousands (or tens of thousands) of MSS-sized segments (for MSS the sender's MAXIMUM SEGMENT SIZE), the current slow-start procedure can result in increasing the congestion window by thousands of segments in a single round-trip time. Such an increase can easily result in thousands of packets being dropped in one round-trip time. This is often counter-productive for the TCP flow itself, and is also hard on the rest of the traffic sharing the congested link. This note describes Limited Slow-Start as an optional mechanism for limiting the number of segments by which the congestion window is increased for one window of data during slow-start, in order to improve performance for TCP connections with large congestion windows. This memo defines an Experimental Protocol for the Internet community.
RFC3758 - Stream Control Transmission Protocol (SCTP) Partial Reliability Extension: This memo describes an extension to the Stream Control Transmission Protocol (SCTP) that allows an SCTP endpoint to signal to its peer that it should move the cumulative ack point forward. When both sides of an SCTP association support this extension, it can be used by an SCTP implementation to provide partially reliable data transmission service to an upper layer protocol. This memo describes the protocol extensions, which consist of a new parameter for INIT and INIT ACK, and a new FORWARD TSN chunk type, and provides one example of a partially reliable service that can be provided to the upper layer via this mechanism. [STANDARDS-TRACK]
RFC3782 - The NewReno Modification to TCP's Fast Recovery Algorithm: The purpose of this document is to advance NewReno TCP's Fast Retransmit and Fast Recovery algorithms in RFC 2582 from Experimental to Standards Track status. The main change in this document relative to RFC 2582 is to specify the Careful variant of NewReno's Fast Retransmit and Fast Recovery algorithms. The base algorithm described in RFC 2582 did not attempt to avoid unnecessary multiple Fast Retransmits that can occur after a timeout. However, RFC 2582 also defined "Careful" and "Less Careful" variants that avoid these unnecessary Fast Retransmits, and recommended the Careful variant. This document specifies the previously-named "Careful" variant as the basic version of NewReno TCP. [STANDARDS-TRACK]
RFC3828 - The Lightweight User Datagram Protocol (UDP-Lite): This document describes the Lightweight User Datagram Protocol (UDP-Lite), which is similar to the User Datagram Protocol (UDP) (RFC 768), but can also serve applications in error-prone network environments that prefer to have partially damaged payloads delivered rather than discarded. If this feature is not used, UDP-Lite is semantically identical to UDP. [STANDARDS-TRACK]
RFC4015 - The Eifel Response Algorithm for TCP: Based on an appropriate detection algorithm, the Eifel response algorithm provides a way for a TCP sender to respond to a detected spurious timeout. It adapts the retransmission timer to avoid further spurious timeouts and (depending on the detection algorithm) can avoid the often unnecessary go-back-N retransmits that would otherwise be sent. In addition, the Eifel response algorithm restores the congestion control state in such a way that packet bursts are avoided. [STANDARDS-TRACK]
RFC4460 - Stream Control Transmission Protocol (SCTP) Specification Errata and Issues: This document is a compilation of issues found during six interoperability events and 5 years of experience with implementing, testing, and using SCTP along with the suggested fixes. This document provides deltas to RFC 2960 and is organized in a time-based way. The issues are listed in the order they were brought up. Because some text is changed several times, the last delta in the text is the one that should be applied. In addition to the delta, a description of the problem and the details of the solution are also provided. This memo provides information for the Internet community.
RFC4495 - A Resource Reservation Protocol (RSVP) Extension for the Reduction of Bandwidth of a Reservation Flow: This document proposes an extension to the Resource Reservation Protocol (RSVPv1) to reduce the guaranteed bandwidth allocated to an existing reservation. This mechanism can be used to affect individual reservations, aggregate reservations, or other forms of RSVP tunnels. This specification is an extension of RFC 2205. [STANDARDS-TRACK]
RFC4542 - Implementing an Emergency Telecommunications Service (ETS) for Real-Time Services in the Internet Protocol Suite: RFCs 3689 and 3690 detail requirements for an Emergency Telecommunications Service (ETS), of which an Internet Emergency Preparedness Service (IEPS) would be a part. Some of these types of services require call preemption; others require call queuing or other mechanisms. IEPS requires a Call Admission Control (CAC) procedure and a Per Hop Behavior (PHB) for the data that meet the needs of this architecture. Such a CAC procedure and PHB is appropriate to any service that might use H.323 or SIP to set up real-time sessions. The key requirement is to guarantee an elevated probability of call completion to an authorized user in time of crisis.; This document primarily discusses supporting ETS in the context of the US Government and NATO, because it focuses on the Multi-Level Precedence and Preemption (MLPP) and Government Emergency Telecommunication Service (GETS) standards. The architectures described here are applicable beyond these organizations. This memo provides information for the Internet community.
RFC4594 - Configuration Guidelines for DiffServ Service Classes: This document describes service classes configured with Diffserv and recommends how they can be used and how to construct them using Differentiated Services Code Points (DSCPs), traffic conditioners, Per-Hop Behaviors (PHBs), and Active Queue Management (AQM) mechanisms. There is no intrinsic requirement that particular DSCPs, traffic conditioners, PHBs, and AQM be used for a certain service class, but as a policy and for interoperability it is useful to apply them consistently. This memo provides information for the Internet community.
RFC4774 - Specifying Alternate Semantics for the Explicit Congestion Notification (ECN) Field: There have been a number of proposals for alternate semantics for the Explicit Congestion Notification (ECN) field in the IP header RFC 3168. This document discusses some of the issues in defining alternate semantics for the ECN field, and specifies requirements for a safe coexistence in an Internet that could include routers that do not understand the defined alternate semantics. This document evolved as a result of discussions with the authors of one recent proposal for such alternate semantics. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC4782 - Quick-Start for TCP and IP: This document specifies an optional Quick-Start mechanism for transport protocols, in cooperation with routers, to determine an allowed sending rate at the start and, at times, in the middle of a data transfer (e.g., after an idle period). While Quick-Start is designed to be used by a range of transport protocols, in this document we only specify its use with TCP. Quick-Start is designed to allow connections to use higher sending rates when there is significant unused bandwidth along the path, and the sender and all of the routers along the path approve the Quick-Start Request.; This document describes many paths where Quick-Start Requests would not be approved. These paths include all paths containing routers, IP tunnels, MPLS paths, and the like that do not support Quick- Start. These paths also include paths with routers or middleboxes that drop packets containing IP options. Quick-Start Requests could be difficult to approve over paths that include multi-access layer- two networks. This document also describes environments where the Quick-Start process could fail with false positives, with the sender incorrectly assuming that the Quick-Start Request had been approved by all of the routers along the path. As a result of these concerns, and as a result of the difficulties and seeming absence of motivation for routers, such as core routers to deploy Quick-Start, Quick-Start is being proposed as a mechanism that could be of use in controlled environments, and not as a mechanism that would be intended or appropriate for ubiquitous deployment in the global Internet. This memo defines an Experimental Protocol for the Internet community.
RFC4804 - Aggregation of Resource ReSerVation Protocol (RSVP) Reservations over MPLS TE/DS-TE Tunnels: RFC 3175 specifies aggregation of Resource ReSerVation Protocol (RSVP) end-to-end reservations over aggregate RSVP reservations. This document specifies aggregation of RSVP end-to-end reservations over MPLS Traffic Engineering (TE) tunnels or MPLS Diffserv-aware MPLS Traffic Engineering (DS-TE) tunnels. This approach is based on RFC 3175 and simply modifies the corresponding procedures for operations over MPLS TE tunnels instead of aggregate RSVP reservations. This approach can be used to achieve admission control of a very large number of flows in a scalable manner since the devices in the core of the network are unaware of the end-to-end RSVP reservations and are only aware of the MPLS TE tunnels. [STANDARDS-TRACK]
RFC4820 - Padding Chunk and Parameter for the Stream Control Transmission Protocol (SCTP): This document defines a padding chunk and a padding parameter and describes the required receiver side procedures. The padding chunk is used to pad a Stream Control Transmission Protocol (SCTP) packet to an arbitrary size. The padding parameter is used to pad an SCTP INIT chunk to an arbitrary size. [STANDARDS-TRACK]
RFC4860 - Generic Aggregate Resource ReSerVation Protocol (RSVP) Reservations: RFC 3175 defines aggregate Resource ReSerVation Protocol (RSVP) reservations allowing resources to be reserved in a Diffserv network for a given Per Hop Behavior (PHB), or given set of PHBs, from a given source to a given destination. RFC 3175 also defines how end-to-end RSVP reservations can be aggregated onto such aggregate reservations when transiting through a Diffserv cloud. There are situations where multiple such aggregate reservations are needed for the same source IP address, destination IP address, and PHB (or set of PHBs). However, this is not supported by the aggregate reservations defined in RFC 3175. In order to support this, the present document defines a more flexible type of aggregate RSVP reservations, referred to as generic aggregate reservation. Multiple such generic aggregate reservations can be established for a given PHB (or set of PHBs) from a given source IP address to a given destination IP address. The generic aggregate reservations may be used to aggregate end-to-end RSVP reservations. This document also defines the procedures for such aggregation. The generic aggregate reservations may also be used end-to-end directly by end-systems attached to a Diffserv network. [STANDARDS-TRACK]
RFC4895 - Authenticated Chunks for the Stream Control Transmission Protocol (SCTP): This document describes a new chunk type, several parameters, and procedures for the Stream Control Transmission Protocol (SCTP). This new chunk type can be used to authenticate SCTP chunks by using shared keys between the sender and receiver. The new parameters are used to establish the shared keys. [STANDARDS-TRACK]
RFC4898 - TCP Extended Statistics MIB: This document describes extended performance statistics for TCP. They are designed to use TCP's ideal vantage point to diagnose performance problems in both the network and the application. If a network-based application is performing poorly, TCP can determine if the bottleneck is in the sender, the receiver, or the network itself. If the bottleneck is in the network, TCP can provide specific information about its nature. [STANDARDS-TRACK]
RFC4923 - Quality of Service (QoS) Signaling in a Nested Virtual Private Network: Some networks require communication between an interior and exterior portion of a Virtual Private Network (VPN) or through a concatenation of such networks resulting in a nested VPN, but have sensitivities about what information is communicated across the boundary, especially while providing quality of service to communications with different precedence. This note seeks to outline the issues and the nature of the proposed solutions based on the framework for Integrated Services operation over Diffserv networks as described in RFC 2998. This memo provides information for the Internet community.
RFC4960 - Stream Control Transmission Protocol: This document obsoletes RFC 2960 and RFC 3309. It describes the Stream Control Transmission Protocol (SCTP). SCTP is designed to transport Public Switched Telephone Network (PSTN) signaling messages over IP networks, but is capable of broader applications.; SCTP is a reliable transport protocol operating on top of a connectionless packet network such as IP. It offers the following services to its users:; -- acknowledged error-free non-duplicated transfer of user data,; -- data fragmentation to conform to discovered path MTU size,; -- sequenced delivery of user messages within multiple streams, with an option for order-of-arrival delivery of individual user messages,; -- optional bundling of multiple user messages into a single SCTP packet, and; -- network-level fault tolerance through supporting of multi-homing at either or both ends of an association.; The design of SCTP includes appropriate congestion avoidance behavior and resistance to flooding and masquerade attacks. [STANDARDS-TRACK]
RFC5033 - Specifying New Congestion Control Algorithms: The IETF's standard congestion control schemes have been widely shown to be inadequate for various environments (e.g., high-speed networks). Recent research has yielded many alternate congestion control schemes that significantly differ from the IETF's congestion control principles. Using these new congestion control schemes in the global Internet has possible ramifications to both the traffic using the new congestion control and to traffic using the currently standardized congestion control. Therefore, the IETF must proceed with caution when dealing with alternate congestion control proposals. The goal of this document is to provide guidance for considering alternate congestion control algorithms within the IETF. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC5061 - Stream Control Transmission Protocol (SCTP) Dynamic Address Reconfiguration: A local host may have multiple points of attachment to the Internet, giving it a degree of fault tolerance from hardware failures. Stream Control Transmission Protocol (SCTP) (RFC 4960) was developed to take full advantage of such a multi-homed host to provide a fast failover and association survivability in the face of such hardware failures. This document describes an extension to SCTP that will allow an SCTP stack to dynamically add an IP address to an SCTP association, dynamically delete an IP address from an SCTP association, and to request to set the primary address the peer will use when sending to an endpoint. [STANDARDS-TRACK]
RFC5062 - Security Attacks Found Against the Stream Control Transmission Protocol (SCTP) and Current Countermeasures: This document describes certain security threats to SCTP. It also describes ways to mitigate these threats, in particular by using techniques from the SCTP Specification Errata and Issues memo (RFC 4460). These techniques are included in RFC 4960, which obsoletes RFC 2960. It is hoped that this information will provide some useful background information for many of the newest requirements spelled out in the SCTP Specification Errata and Issues and included in RFC 4960. This memo provides information for the Internet community.
RFC5097 - MIB for the UDP-Lite protocol: This document specifies a Management Information Base (MIB) module for the Lightweight User Datagram Protocol (UDP-Lite). It defines a set of new MIB objects to characterise the behaviour and performance of transport layer endpoints deploying UDP-Lite. UDP-Lite resembles UDP, but differs from the semantics of UDP by the addition of a single option. This adds the capability for variable-length data checksum coverage, which can benefit a class of applications that prefer delivery of (partially) corrupted datagram payload data in preference to discarding the datagram. [STANDARDS-TRACK]
RFC5127 - Aggregation of Diffserv Service Classes: In the core of a high-capacity network, service differentiation may still be needed to support applications' utilization of the network. Applications with similar traffic characteristics and performance requirements are mapped into Diffserv service classes based on end- to-end behavior requirements of the applications. However, some network segments may be configured in such a way that a single forwarding treatment may satisfy the traffic characteristics and performance requirements of two or more service classes. In these cases, it may be desirable to aggregate two or more Diffserv service classes into a single forwarding treatment. This document provides guidelines for the aggregation of Diffserv service classes into forwarding treatments. This memo provides information for the Internet community.
RFC5129 - Explicit Congestion Marking in MPLS: RFC 3270 defines how to support the Diffserv architecture in MPLS networks, including how to encode Diffserv Code Points (DSCPs) in an MPLS header. DSCPs may be encoded in the EXP field, while other uses of that field are not precluded. RFC 3270 makes no statement about how Explicit Congestion Notification (ECN) marking might be encoded in the MPLS header. This document defines how an operator might define some of the EXP codepoints for explicit congestion notification, without precluding other uses. [STANDARDS-TRACK]
RFC5284 - User-Defined Errors for RSVP: The Resource ReserVation Protocol (RSVP) defines an ERROR_SPEC object for communicating errors. That object has a defined format that permits the definition of 256 error codes. As RSVP has been developed and extended, the convention has been to be conservative in defining new error codes. Further, no provision for user-defined errors exists in RSVP.; This document defines a USER_ERROR_SPEC to be used in addition to the ERROR_SPEC to carry additional user information related to errors. [STANDARDS-TRACK]
RFC5405 - Unicast UDP Usage Guidelines for Application Designers: The User Datagram Protocol (UDP) provides a minimal message-passing transport that has no inherent congestion control mechanisms. Because congestion control is critical to the stable operation of the Internet, applications and upper-layer protocols that choose to use UDP as an Internet transport must employ mechanisms to prevent congestion collapse and to establish some degree of fairness with concurrent traffic. This document provides guidelines on the use of UDP for the designers of unicast applications and upper-layer protocols. Congestion control guidelines are a primary focus, but the document also provides guidance on other topics, including message sizes, reliability, checksums, and middlebox traversal. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC5865 - A Differentiated Services Code Point (DSCP) for Capacity-Admitted Traffic: This document requests one Differentiated Services Code Point (DSCP) from the Internet Assigned Numbers Authority (IANA) for a class of real-time traffic. This traffic class conforms to the Expedited Forwarding Per-Hop Behavior. This traffic is also admitted by the network using a Call Admission Control (CAC) procedure involving authentication, authorization, and capacity admission. This differs from a real-time traffic class that conforms to the Expedited Forwarding Per-Hop Behavior but is not subject to capacity admission or subject to very coarse capacity admission. [STANDARDS-TRACK]
RFC5945 - Resource Reservation Protocol (RSVP) Proxy Approaches: The Resource Reservation Protocol (RSVP) can be used to make end-to- end resource reservations in an IP network in order to guarantee the quality of service required by certain flows. RSVP assumes that both the data sender and receiver of a given flow take part in RSVP signaling. Yet, there are use cases where resource reservation is required, but the receiver, the sender, or both, is not RSVP-capable. This document presents RSVP proxy behaviors allowing RSVP routers to initiate or terminate RSVP signaling on behalf of a receiver or a sender that is not RSVP-capable. This allows resource reservations to be established on a critical subset of the end-to-end path. This document reviews conceptual approaches for deploying RSVP proxies and discusses how RSVP reservations can be synchronized with application requirements, despite the sender, receiver, or both not participating in RSVP. This document also points out where extensions to RSVP (or to other protocols) may be needed for deployment of a given RSVP proxy approach. However, such extensions are outside the scope of this document. Finally, practical use cases for RSVP proxy are described. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC5946 - Resource Reservation Protocol (RSVP) Extensions for Path-Triggered RSVP Receiver Proxy: Resource Reservation Protocol (RSVP) signaling can be used to make end-to-end resource reservations in an IP network in order to guarantee the Quality of Service (QoS) required by certain flows. With conventional RSVP, both the data sender and receiver of a given flow take part in RSVP signaling. Yet, there are many use cases where resource reservation is required, but the receiver, the sender, or both, is not RSVP-capable. Where the receiver is not RSVP- capable, an RSVP router may behave as an RSVP Receiver Proxy, thereby performing RSVP signaling on behalf of the receiver. This allows resource reservations to be established on the segment of the end-to- end path from the sender to the RSVP Receiver Proxy. However, as discussed in the companion document "RSVP Proxy Approaches", RSVP extensions are needed to facilitate operations with an RSVP Receiver Proxy whose signaling is triggered by receipt of RSVP Path messages from the sender. This document specifies these extensions. [STANDARDS-TRACK]
RFC6016 - Support for the Resource Reservation Protocol (RSVP) in Layer 3 VPNs: RFC 4364 and RFC 4659 define an approach to building provider-provisioned Layer 3 VPNs (L3VPNs) for IPv4 and IPv6. It may be desirable to use Resource Reservation Protocol (RSVP) to perform admission control on the links between Customer Edge (CE) routers and Provider Edge (PE) routers. This document specifies procedures by which RSVP messages traveling from CE to CE across an L3VPN may be appropriately handled by PE routers so that admission control can be performed on PE-CE links. Optionally, admission control across the provider's backbone may also be supported. [STANDARDS-TRACK]
RFC6040 - Tunnelling of Explicit Congestion Notification: This document redefines how the explicit congestion notification (ECN) field of the IP header should be constructed on entry to and exit from any IP-in-IP tunnel. On encapsulation, it updates RFC 3168 to bring all IP-in-IP tunnels (v4 or v6) into line with RFC 4301 IPsec ECN processing. On decapsulation, it updates both RFC 3168 and RFC 4301 to add new behaviours for previously unused combinations of inner and outer headers. The new rules ensure the ECN field is correctly propagated across a tunnel whether it is used to signal one or two severity levels of congestion; whereas before, only one severity level was supported. Tunnel endpoints can be updated in any order without affecting pre-existing uses of the ECN field, thus ensuring backward compatibility. Nonetheless, operators wanting to support two severity levels (e.g., for pre-congestion notification -- PCN) can require compliance with this new specification. A thorough analysis of the reasoning for these changes and the implications is included. In the unlikely event that the new rules do not meet a specific need, RFC 4774 gives guidance on designing alternate ECN semantics, and this document extends that to include tunnelling issues. [STANDARDS-TRACK]
RFC6056 - Recommendations for Transport-Protocol Port Randomization: During the last few years, awareness has been raised about a number of "blind" attacks that can be performed against the Transmission Control Protocol (TCP) and similar protocols. The consequences of these attacks range from throughput reduction to broken connections or data corruption. These attacks rely on the attacker's ability to guess or know the five-tuple (Protocol, Source Address, Destination Address, Source Port, Destination Port) that identifies the transport protocol instance to be attacked. This document describes a number of simple and efficient methods for the selection of the client port number, such that the possibility of an attacker guessing the exact value is reduced. While this is not a replacement for cryptographic methods for protecting the transport-protocol instance, the aforementioned port selection algorithms provide improved security with very little effort and without any key management overhead. The algorithms described in this document are local policies that may be incrementally deployed and that do not violate the specifications of any of the transport protocols that may benefit from them, such as TCP, UDP, UDP-lite, Stream Control Transmission Protocol (SCTP), Datagram Congestion Control Protocol (DCCP), and RTP (provided that the RTP application explicitly signals the RTP and RTCP port numbers). This memo documents an Internet Best Current Practice.
RFC6083 - Datagram Transport Layer Security (DTLS) for Stream Control Transmission Protocol (SCTP): This document describes the usage of the Datagram Transport Layer Security (DTLS) protocol over the Stream Control Transmission Protocol (SCTP).; DTLS over SCTP provides communications privacy for applications that use SCTP as their transport protocol and allows client/server applications to communicate in a way that is designed to prevent eavesdropping and detect tampering or message forgery.; Applications using DTLS over SCTP can use almost all transport features provided by SCTP and its extensions. [STANDARDS-TRACK]
RFC6096 - Stream Control Transmission Protocol (SCTP) Chunk Flags Registration: This document defines the procedure for registering chunk flags with the Internet Assigned Numbers Authority (IANA) for the Stream Control Transmission Protocol (SCTP). It updates RFC 4960 and also defines the IANA registry for contents for currently defined chunk types. It does not change SCTP in any other way. [STANDARDS-TRACK]
RFC6335 - Internet Assigned Numbers Authority (IANA) Procedures for the Management of the Service Name and Transport Protocol Port Number Registry: This document defines the procedures that the Internet Assigned Numbers Authority (IANA) uses when handling assignment and other requests related to the Service Name and Transport Protocol Port Number registry. It also discusses the rationale and principles behind these procedures and how they facilitate the long-term sustainability of the registry.; This document updates IANA's procedures by obsoleting the previous UDP and TCP port assignment procedures defined in Sections 8 and 9.1 of the IANA Allocation Guidelines, and it updates the IANA service name and port assignment procedures for UDP-Lite, the Datagram Congestion Control Protocol (DCCP), and the Stream Control Transmission Protocol (SCTP). It also updates the DNS SRV specification to clarify what a service name is and how it is registered. This memo documents an Internet Best Current Practice.
RFC6401 - RSVP Extensions for Admission Priority: Some applications require the ability to provide an elevated probability of session establishment to specific sessions in times of network congestion. When supported over the Internet Protocol suite, this may be facilitated through a network-layer admission control solution that supports prioritized access to resources (e.g., bandwidth). These resources may be explicitly set aside for prioritized sessions, or may be shared with other sessions. This document specifies extensions to the Resource reSerVation Protocol (RSVP) that can be used to support such an admission priority capability at the network layer.; Based on current security concerns, these extensions are intended for use in a single administrative domain. [STANDARDS-TRACK]
RFC6411 - Applicability of Keying Methods for RSVP Security: The Resource reSerVation Protocol (RSVP) allows hop-by-hop integrity protection of RSVP neighbors. This requires messages to be cryptographically protected using a shared secret between participating nodes. This document compares group keying for RSVP with per-neighbor or per-interface keying, and discusses the associated key provisioning methods as well as applicability and limitations of these approaches. This document also discusses applicability of encrypting RSVP messages. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC6458 - Sockets API Extensions for the Stream Control Transmission Protocol (SCTP): This document describes a mapping of the Stream Control Transmission Protocol (SCTP) into a sockets API. The benefits of this mapping include compatibility for TCP applications, access to new SCTP features, and a consolidated error and event notification scheme. This document is not an Internet Standards Track specification; it is published for informational purposes.
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]
RFC6633 - Deprecation of ICMP Source Quench Messages: This document formally deprecates the use of ICMP Source Quench messages by transport protocols, formally updating RFC 792, RFC 1122, and RFC 1812. [STANDARDS-TRACK]
RFC6951 - UDP Encapsulation of Stream Control Transmission Protocol (SCTP) Packets for End-Host to End-Host Communication: This document describes a simple method of encapsulating Stream Control Transmission Protocol (SCTP) packets into UDP packets and its limitations. This allows the usage of SCTP in networks with legacy NATs that do not support SCTP. It can also be used to implement SCTP on hosts without directly accessing the IP layer, for example, implementing it as part of the application without requiring special privileges.; Please note that this document only describes the functionality required within an SCTP stack to add on UDP encapsulation, providing only those mechanisms for two end-hosts to communicate with each other over UDP ports. In particular, it does not provide mechanisms to determine whether UDP encapsulation is being used by the peer, nor the mechanisms for determining which remote UDP port number can be used. These functions are out of scope for this document.; This document covers only end-hosts and not tunneling (egress or ingress) endpoints.
RFC7053 - SACK-IMMEDIATELY Extension for the Stream Control Transmission Protocol: This document updates RFC 4960 by defining a method for the sender of a DATA chunk to indicate that the corresponding Selective Acknowledgment (SACK) chunk should be sent back immediately and should not be delayed. It is done by specifying a bit in the DATA chunk header, called the (I)mmediate bit, which can get set by either the Stream Control Transmission Protocol (SCTP) implementation or the application using an SCTP stack. Since unknown flags in chunk headers are ignored by SCTP implementations, this extension does not introduce any interoperability problems.
RFC7141 - Byte and Packet Congestion Notification: This document provides recommendations of best current practice for dropping or marking packets using any active queue management (AQM) algorithm, including Random Early Detection (RED), BLUE, Pre- Congestion Notification (PCN), and newer schemes such as CoDel (Controlled Delay) and PIE (Proportional Integral controller Enhanced). We give three strong recommendations: (1) packet size should be taken into account when transports detect and respond to congestion indications, (2) packet size should not be taken into account when network equipment creates congestion signals (marking, dropping), and therefore (3) in the specific case of RED, the byte- mode packet drop variant that drops fewer small packets should not be used. This memo updates RFC 2309 to deprecate deliberate preferential treatment of small packets in AQM algorithms.
RFC7417 - Extensions to Generic Aggregate RSVP for IPv4 and IPv6 Reservations over Pre-Congestion Notification (PCN) Domains: This document specifies extensions to Generic Aggregate RSVP (RFC 4860) for support of the Pre-Congestion Notification (PCN) Controlled Load (CL) and Single Marking (SM) edge behaviors over a Diffserv cloud using PCN.
RFC7496 - Additional Policies for the Partially Reliable Stream Control Transmission Protocol Extension: This document defines two additional policies for the Partially Reliable Stream Control Transmission Protocol (PR-SCTP) extension. These policies allow limitation of the number of retransmissions and prioritization of user messages for more efficient usage of the send buffer.
RFC7605 - Recommendations on Using Assigned Transport Port Numbers: This document provides recommendations to designers of application and service protocols on how to use the transport protocol port number space and when to request a port assignment from IANA. It provides designer guidance to requesters or users of port numbers on how to interact with IANA using the processes defined in RFC 6335; thus, this document complements (but does not update) that document.
RFC7829 - SCTP-PF: A Quick Failover Algorithm for the Stream Control Transmission Protocol: The Stream Control Transmission Protocol (SCTP) supports multihoming. However, when the failover operation specified in RFC 4960 is followed, there can be significant delay and performance degradation in the data transfer path failover. This document specifies a quick failover algorithm and introduces the SCTP Potentially Failed (SCTP-PF) destination state in SCTP Path Management.; This document also specifies a dormant state operation of SCTP that is required to be followed by an SCTP-PF implementation, but it may equally well be applied by a standard SCTP implementation, as described in RFC 4960.; Additionally, this document introduces an alternative switchback operation mode called "Primary Path Switchover" that will be beneficial in certain situations. This mode of operation applies to both a standard SCTP implementation and an SCTP-PF implementation.; The procedures defined in the document require only minimal modifications to the specification in RFC 4960. The procedures are sender-side only and do not impact the SCTP receiver.
RFC7857 - Updates to Network Address Translation (NAT) Behavioral Requirements: This document clarifies and updates several requirements of RFCs 4787, 5382, and 5508 based on operational and development experience. The focus of this document is Network Address Translation from IPv4 to IPv4 (NAT44).; This document updates RFCs 4787, 5382, and 5508.
RFC8084 - Network Transport Circuit Breakers: This document explains what is meant by the term "network transport Circuit Breaker". It describes the need for Circuit Breakers (CBs) for network tunnels and applications when using non-congestion- controlled traffic and explains where CBs are, and are not, needed. It also defines requirements for building a CB and the expected outcomes of using a CB within the Internet.
RFC8085 - UDP Usage Guidelines: The User Datagram Protocol (UDP) provides a minimal message-passing transport that has no inherent congestion control mechanisms. This document provides guidelines on the use of UDP for the designers of applications, tunnels, and other protocols that use UDP. Congestion control guidelines are a primary focus, but the document also provides guidance on other topics, including message sizes, reliability, checksums, middlebox traversal, the use of Explicit Congestion Notification (ECN), Differentiated Services Code Points (DSCPs), and ports.; Because congestion control is critical to the stable operation of the Internet, applications and other protocols that choose to use UDP as an Internet transport must employ mechanisms to prevent congestion collapse and to establish some degree of fairness with concurrent traffic. They may also need to implement additional mechanisms, depending on how they use UDP.; Some guidance is also applicable to the design of other protocols (e.g., protocols layered directly on IP or via IP-based tunnels), especially when these protocols do not themselves provide congestion control.; This document obsoletes RFC 5405 and adds guidelines for multicast UDP usage.
RFC8086 - GRE-in-UDP Encapsulation: This document specifies a method of encapsulating network protocol packets within GRE and UDP headers. This GRE-in-UDP encapsulation allows the UDP source port field to be used as an entropy field. This may be used for load-balancing of GRE traffic in transit networks using existing Equal-Cost Multipath (ECMP) mechanisms. There are two applicability scenarios for GRE-in-UDP with different requirements: (1) general Internet and (2) a traffic-managed controlled environment. The controlled environment has less restrictive requirements than the general Internet.
RFC8100 - Diffserv-Interconnection Classes and Practice: This document defines a limited common set of Diffserv Per-Hop Behaviors (PHBs) and Diffserv Codepoints (DSCPs) to be applied at (inter)connections of two separately administered and operated networks, and it explains how this approach can simplify network configuration and operation. Many network providers operate Multiprotocol Label Switching (MPLS) using Treatment Aggregates for traffic marked with different Diffserv Per-Hop Behaviors and use MPLS for interconnection with other networks. This document offers a simple interconnection approach that may simplify operation of Diffserv for network interconnection among providers that use MPLS and apply the Short Pipe Model. While motivated by the requirements of MPLS network operators that use Short Pipe Model tunnels, this document is applicable to other networks, both MPLS and non-MPLS.
RFC8260 - Stream Schedulers and User Message Interleaving for the Stream Control Transmission Protocol: The Stream Control Transmission Protocol (SCTP) is a message-oriented transport protocol supporting arbitrarily large user messages. This document adds a new chunk to SCTP for carrying payload data. This allows a sender to interleave different user messages that would otherwise result in head-of-line blocking at the sender. The interleaving of user messages is required for WebRTC data channels.; Whenever an SCTP sender is allowed to send user data, it may choose from multiple outgoing SCTP streams. Multiple ways for performing this selection, called stream schedulers, are defined in this document. A stream scheduler can choose to either implement, or not implement, user message interleaving.
RFC8261 - Datagram Transport Layer Security (DTLS) Encapsulation of SCTP Packets: The Stream Control Transmission Protocol (SCTP) is a transport protocol originally defined to run on top of the network protocols IPv4 or IPv6. This document specifies how SCTP can be used on top of the Datagram Transport Layer Security (DTLS) protocol. Using the encapsulation method described in this document, SCTP is unaware of the protocols being used below DTLS; hence, explicit IP addresses cannot be used in the SCTP control chunks. As a consequence, the SCTP associations carried over DTLS can only be single-homed.
RFC8311 - Relaxing Restrictions on Explicit Congestion Notification (ECN) Experimentation: This memo updates RFC 3168, which specifies Explicit Congestion Notification (ECN) as an alternative to packet drops for indicating network congestion to endpoints. It relaxes restrictions in RFC 3168 that hinder experimentation towards benefits beyond just removal of loss. This memo summarizes the anticipated areas of experimentation and updates RFC 3168 to enable experimentation in these areas. An Experimental RFC in the IETF document stream is required to take advantage of any of these enabling updates. In addition, this memo makes related updates to the ECN specifications for RTP in RFC 6679 and for the Datagram Congestion Control Protocol (DCCP) in RFCs 4341, 4342, and 5622. This memo also records the conclusion of the ECN nonce experiment in RFC 3540 and provides the rationale for reclassification of RFC 3540 from Experimental to Historic; this reclassification enables new experimental use of the ECT(1) codepoint.
RFC8325 - Mapping Diffserv to IEEE 802.11: As Internet traffic is increasingly sourced from and destined to wireless endpoints, it is crucial that Quality of Service (QoS) be aligned between wired and wireless networks; however, this is not always the case by default. This document specifies a set of mappings from Differentiated Services Code Point (DSCP) to IEEE 802.11 User Priority (UP) to reconcile the marking recommendations offered by the IETF and the IEEE so as to maintain consistent QoS treatment between wired and IEEE 802.11 wireless networks.
RFC8436 - Update to IANA Registration Procedures for Pool 3 Values in the Differentiated Services Field Codepoints (DSCP) Registry: The Differentiated Services (Diffserv) architecture specifies use of the DS field in the IPv4 and IPv6 packet headers to carry one of 64 distinct differentiated services field codepoint (DSCP) values. The Internet Assigned Numbers Authority (IANA) maintains a registry of assigned DSCP values.; This update to RFC 2474 changes the IANA registration policy for Pool 3 of the registry (i.e., DSCP values of the form xxxx01) to Standards Action, i.e., values are assigned through a Standards Track or Best Current Practice RFC. The update also removes permission for experimental and local use of the codepoints that form Pool 3 of the DSCP registry; Pool 2 Codepoints (i.e., DSCP values of the form xxxx11) remain available for these purposes.
RFC8540 - Stream Control Transmission Protocol: Errata and Issues in RFC 4960: This document is a compilation of issues found since the publication of RFC 4960 in September 2007, based on experience with implementing, testing, and using the Stream Control Transmission Protocol (SCTP) along with the suggested fixes. This document provides deltas to RFC 4960 and is organized in a time-ordered way. The issues are listed in the order in which they were brought up. Because some text is changed several times, the last delta in the text is the one that should be applied. In addition to the deltas, a description of each problem and the details of the solution for each are also provided.
RFC8622 - A Lower-Effort Per-Hop Behavior (LE PHB) for Differentiated Services: This document specifies properties and characteristics of a Lower- Effort Per-Hop Behavior (LE PHB). The primary objective of this LE PHB is to protect Best-Effort (BE) traffic (packets forwarded with the default PHB) from LE traffic in congestion situations, i.e., when resources become scarce, BE traffic has precedence over LE traffic and may preempt it. Alternatively, packets forwarded by the LE PHB can be associated with a scavenger service class, i.e., they scavenge otherwise-unused resources only. There are numerous uses for this PHB, e.g., for background traffic of low precedence, such as bulk data transfers with low priority in time, non-time-critical backups, larger software updates, web search engines while gathering information from web servers and so on. This document recommends a standard Differentiated Services Code Point (DSCP) value for the LE PHB.; This specification obsoletes RFC 3662 and updates the DSCP recommended in RFCs 4594 and 8325 to use the DSCP assigned in this specification.
RFC8680 - Forward Error Correction (FEC) Framework Extension to Sliding Window Codes: RFC 6363 describes a framework for using Forward Error Correction (FEC) codes to provide protection against packet loss. The framework supports applying FEC to arbitrary packet flows over unreliable transport and is primarily intended for real-time, or streaming, media. However, FECFRAME as per RFC 6363 is restricted to block FEC codes. This document updates RFC 6363 to support FEC codes based on a sliding encoding window, in addition to block FEC codes, in a backward-compatible way. During multicast/broadcast real-time content delivery, the use of sliding window codes significantly improves robustness in harsh environments, with less repair traffic and lower FEC-related added latency.
RFC8681 - Sliding Window Random Linear Code (RLC) Forward Erasure Correction (FEC) Schemes for FECFRAME: This document describes two fully specified Forward Erasure Correction (FEC) Schemes for Sliding Window Random Linear Codes (RLC), one for RLC over the Galois Field (a.k.a., Finite Field) GF(2), a second one for RLC over the Galois Field GF(2), each time with the possibility of controlling the code density. They can protect arbitrary media streams along the lines defined by FECFRAME extended to Sliding Window FEC Codes. These Sliding Window FEC Codes rely on an encoding window that slides over the source symbols, generating new repair symbols whenever needed. Compared to block FEC codes, these Sliding Window FEC Codes offer key advantages with real-time flows in terms of reduced FEC-related latency while often providing improved packet erasure recovery capabilities.
RFC8682 - TinyMT32 Pseudorandom Number Generator (PRNG): This document describes the TinyMT32 Pseudorandom Number Generator (PRNG), which produces 32-bit pseudorandom unsigned integers and aims at having a simple-to-use and deterministic solution. This PRNG is a small-sized variant of the Mersenne Twister (MT) PRNG. The main advantage of TinyMT32 over MT is the use of a small internal state, compatible with most target platforms that include embedded devices, while keeping reasonably good randomness that represents a significant improvement compared to the Park-Miller Linear Congruential PRNG. However, neither the TinyMT nor MT PRNG is meant to be used for cryptographic applications.
RFC8837 - Differentiated Services Code Point (DSCP) Packet Markings for WebRTC QoS: Networks can provide different forwarding treatments for individual packets based on Differentiated Services Code Point (DSCP) values on a per-hop basis. This document provides the recommended DSCP values for web browsers to use for various classes of Web Real-Time Communication (WebRTC) traffic.
RFC8899 - Packetization Layer Path MTU Discovery for Datagram Transports: This document specifies Datagram Packetization Layer Path MTU Discovery (DPLPMTUD). This is a robust method for Path MTU Discovery (PMTUD) for datagram Packetization Layers (PLs). It allows a PL, or a datagram application that uses a PL, to discover whether a network path can support the current size of datagram. This can be used to detect and reduce the message size when a sender encounters a packet black hole. It can also probe a network path to discover whether the maximum packet size can be increased. This provides functionality for datagram transports that is equivalent to the PLPMTUD specification for TCP, specified in RFC 4821, which it updates. It also updates the UDP Usage Guidelines to refer to this method for use with UDP datagrams and updates SCTP.; The document provides implementation notes for incorporating Datagram PMTUD into IETF datagram transports or applications that use datagram transports.; This specification updates RFC 4960, RFC 4821, RFC 6951, RFC 8085, and RFC 8261.
RFC9065 - Considerations around Transport Header Confidentiality, Network Operations, and the Evolution of Internet Transport Protocols: To protect user data and privacy, Internet transport protocols have supported payload encryption and authentication for some time. Such encryption and authentication are now also starting to be applied to the transport protocol headers. This helps avoid transport protocol ossification by middleboxes, mitigate attacks against the transport protocol, and protect metadata about the communication. Current operational practice in some networks inspect transport header information within the network, but this is no longer possible when those transport headers are encrypted.; This document discusses the possible impact when network traffic uses a protocol with an encrypted transport header. It suggests issues to consider when designing new transport protocols or features.
RFC9260 - Stream Control Transmission Protocol: This document describes the Stream Control Transmission Protocol (SCTP) and obsoletes RFC 4960. It incorporates the specification of the chunk flags registry from RFC 6096 and the specification of the I bit of DATA chunks from RFC 7053. Therefore, RFCs 6096 and 7053 are also obsoleted by this document. In addition, RFCs 4460 and 8540, which describe errata for SCTP, are obsoleted by this document.; SCTP was originally designed to transport Public Switched Telephone Network (PSTN) signaling messages over IP networks. It is also suited to be used for other applications, for example, WebRTC.; SCTP is a reliable transport protocol operating on top of a connectionless packet network, such as IP. It offers the following services to its users:; The design of SCTP includes appropriate congestion avoidance behavior and resistance to flooding and masquerade attacks.
RFC9330 - Low Latency, Low Loss, and Scalable Throughput (L4S) Internet Service: Architecture: This document describes the L4S architecture, which enables Internet applications to achieve low queuing latency, low congestion loss, and scalable throughput control. L4S is based on the insight that the root cause of queuing delay is in the capacity-seeking congestion controllers of senders, not in the queue itself. With the L4S architecture, all Internet applications could (but do not have to) transition away from congestion control algorithms that cause substantial queuing delay and instead adopt a new class of congestion controls that can seek capacity with very little queuing. These are aided by a modified form of Explicit Congestion Notification (ECN) from the network. With this new architecture, applications can have both low latency and high throughput.; The architecture primarily concerns incremental deployment. It defines mechanisms that allow the new class of L4S congestion controls to coexist with 'Classic' congestion controls in a shared network. The aim is for L4S latency and throughput to be usually much better (and rarely worse) while typically not impacting Classic performance.
RFC9331 - The Explicit Congestion Notification (ECN) Protocol for Low Latency, Low Loss, and Scalable Throughput (L4S): This specification defines the protocol to be used for a new network service called Low Latency, Low Loss, and Scalable throughput (L4S). L4S uses an Explicit Congestion Notification (ECN) scheme at the IP layer that is similar to the original (or 'Classic') ECN approach, except as specified within. L4S uses 'Scalable' congestion control, which induces much more frequent control signals from the network, and it responds to them with much more fine-grained adjustments so that very low (typically sub-millisecond on average) and consistently low queuing delay becomes possible for L4S traffic without compromising link utilization. Thus, even capacity-seeking (TCP-like) traffic can have high bandwidth and very low delay at the same time, even during periods of high traffic load.; The L4S identifier defined in this document distinguishes L4S from 'Classic' (e.g., TCP-Reno-friendly) traffic. Then, network bottlenecks can be incrementally modified to distinguish and isolate existing traffic that still follows the Classic behaviour, to prevent it from degrading the low queuing delay and low loss of L4S traffic. This Experimental specification defines the rules that L4S transports and network elements need to follow, with the intention that L4S flows neither harm each other's performance nor that of Classic traffic. It also suggests open questions to be investigated during experimentation. Examples of new Active Queue Management (AQM) marking algorithms and new transports (whether TCP-like or real time) are specified separately.
RFC9332 - Dual-Queue Coupled Active Queue Management (AQM) for Low Latency, Low Loss, and Scalable Throughput (L4S): This specification defines a framework for coupling the Active Queue Management (AQM) algorithms in two queues intended for flows with different responses to congestion. This provides a way for the Internet to transition from the scaling problems of standard TCP-Reno-friendly ('Classic') congestion controls to the family of 'Scalable' congestion controls. These are designed for consistently very low queuing latency, very low congestion loss, and scaling of per-flow throughput by using Explicit Congestion Notification (ECN) in a modified way. Until the Coupled Dual Queue (DualQ), these Scalable L4S congestion controls could only be deployed where a clean-slate environment could be arranged, such as in private data centres.; This specification first explains how a Coupled DualQ works. It then gives the normative requirements that are necessary for it to work well. All this is independent of which two AQMs are used, but pseudocode examples of specific AQMs are given in appendices.
RFC9435 - Considerations for Assigning a New Recommended Differentiated Services Code Point (DSCP): This document discusses considerations for assigning a new recommended Differentiated Services Code Point (DSCP) for a standard Per-Hop Behavior (PHB). It considers the common observed re-marking behaviors that the Diffserv field might be subjected to along an Internet path. It also notes some implications of using a specific DSCP.