--- 1/draft-ietf-taps-transports-usage-01.txt 2016-10-31 02:16:21.448442654 -0700 +++ 2/draft-ietf-taps-transports-usage-02.txt 2016-10-31 02:16:21.528444624 -0700 @@ -1,90 +1,91 @@ TAPS M. Welzl Internet-Draft University of Oslo Intended status: Informational M. Tuexen -Expires: January 9, 2017 Muenster Univ. of Appl. Sciences +Expires: May 4, 2017 Muenster Univ. of Appl. Sciences N. Khademi University of Oslo - July 8, 2016 + October 31, 2016 On the Usage of Transport Service Features Provided by IETF Transport Protocols - draft-ietf-taps-transports-usage-01 + draft-ietf-taps-transports-usage-02 Abstract This document describes how transport protocols expose services to applications and how an application can configure and use the features of a transport service. -Status of This Memo +Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on January 9, 2017. + This Internet-Draft will expire on May 4, 2017. Copyright Notice Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents - 1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 - 3. Pass 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 3.1. Primitives Provided by TCP . . . . . . . . . . . . . . . 4 - 3.1.1. Excluded Primitives . . . . . . . . . . . . . . . . . 7 - 3.2. Primitives Provided by MPTCP . . . . . . . . . . . . . . 8 + 1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 + 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 + 3. Pass 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 + 3.1. Primitives Provided by TCP . . . . . . . . . . . . . . . . 5 + 3.1.1. Excluded Primitives or Parameters . . . . . . . . . . 7 + 3.2. Primitives Provided by MPTCP . . . . . . . . . . . . . . . 8 3.3. Primitives Provided by SCTP . . . . . . . . . . . . . . . 9 - 3.3.1. Excluded Primitives . . . . . . . . . . . . . . . . . 12 - 4. Pass 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 4.1. CONNECTION Related Primitives . . . . . . . . . . . . . . 13 - 4.2. DATA Transfer Related Primitives . . . . . . . . . . . . 19 - 5. Pass 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 - 5.1. CONNECTION Related Transport Service Features . . . . . . 21 - 5.2. DATA Transfer Related Transport Service Features . . . . 25 - 5.2.1. Sending Data . . . . . . . . . . . . . . . . . . . . 25 - 5.2.2. Receiving Data . . . . . . . . . . . . . . . . . . . 26 - 5.2.3. Errors . . . . . . . . . . . . . . . . . . . . . . . 27 - 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 27 - 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 27 - 8. Security Considerations . . . . . . . . . . . . . . . . . . . 27 - 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 27 - 9.1. Normative References . . . . . . . . . . . . . . . . . . 27 - 9.2. Informative References . . . . . . . . . . . . . . . . . 28 - Appendix A. Overview of RFCs used as input for pass 1 . . . . . 29 - Appendix B. How to contribute . . . . . . . . . . . . . . . . . 29 - Appendix C. Revision information . . . . . . . . . . . . . . . . 31 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32 + 3.3.1. Excluded Primitives or Parameters . . . . . . . . . . 13 + 3.4. Primitives Provided by UDP and UDP-Lite . . . . . . . . . 14 + 4. Pass 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 + 4.1. CONNECTION Related Primitives . . . . . . . . . . . . . . 14 + 4.2. DATA Transfer Related Primitives . . . . . . . . . . . . . 23 + 5. Pass 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 + 5.1. CONNECTION Related Transport Service Features . . . . . . 25 + 5.2. DATA Transfer Related Transport Service Features . . . . . 30 + 5.2.1. Sending Data . . . . . . . . . . . . . . . . . . . . . 30 + 5.2.2. Receiving Data . . . . . . . . . . . . . . . . . . . . 31 + 5.2.3. Errors . . . . . . . . . . . . . . . . . . . . . . . . 31 + 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 32 + 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 32 + 8. Security Considerations . . . . . . . . . . . . . . . . . . . 32 + 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 32 + 9.1. Normative References . . . . . . . . . . . . . . . . . . . 32 + 9.2. Informative References . . . . . . . . . . . . . . . . . . 33 + Appendix A. Overview of RFCs used as input for pass 1 . . . . . . 35 + Appendix B. How to contribute . . . . . . . . . . . . . . . . . . 36 + Appendix C. Revision information . . . . . . . . . . . . . . . . 37 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 38 1. Terminology Transport Service Feature: a specific end-to-end feature that a transport service provides to its clients. Examples include confidentiality, reliable delivery, ordered delivery, message- versus-stream orientation, etc. Transport Service: a set of transport service features, without an association to any given framing protocol, which provides a complete service to an application. @@ -105,20 +105,22 @@ endpoints using a transport protocol. Connection: shared state of two or more endpoints that persists across messages that are transmitted between these endpoints. Primitive: a function call that is used to locally communicate between an application and a transport endpoint and is related to one or more Transport Service Features. Parameter: a value passed between an application and a transport protocol by a primitive. Socket: the combination of a destination IP address and a destination port number. + Transport Address: the combination of an IP address, transport + protocol and the port number used by the transport protocol. 2. Introduction This document presents defined interactions between transport protocols and applications in the form of 'primitives' (function calls). Primitives can be invoked by an application or a transport protocol; the latter type is called an "event". The list of transport service features and primitives in this document is strictly based on the parts of protocol specifications that relate to what the protocol provides to an application using it and how the @@ -302,21 +303,21 @@ the value of the UTO advertised to the remote TCP peer (default: system-wide default user timeout); ENABLED (default false) is a boolean-type flag that controls whether the UTO option is enabled for a connection. This applies to both sending and receiving. CHANGEABLE is a boolean-type flag (default true) that controls whether the user timeout may be changed based on a UTO option received from the other end of the connection. CHANGEABLE becomes false when an application explicitly sets the user timeout (see 'send'). -3.1.1. Excluded Primitives +3.1.1. Excluded Primitives or Parameters The 'open' primitive specified in [RFC0793] can be handed optional Precedence or security/compartment information according to [RFC0793], but this was not included here because it is mostly irrelevant today, as explained in [RFC7414]. The 'status' primitive was not included because [RFC0793] describes this primitive as "implementation dependent" and states that it "could be excluded without adverse effect". Moreover, while a data block containing specific information is described, it is also stated @@ -366,21 +367,21 @@ send/receive: [RFC6824] states that the sending and receiving of data does not require any changes to the application when MPTCP is being used. The MPTCP-layer will "take one input data stream from an application, and split it into one or more subflows, with sufficient control information to allow it to be reassembled and delivered reliably and in order to the recipient application." The use of the Urgent-Pointer is special in MPTCP and [RFC6824] says "a TCP subflow MUST NOT use the Urgent Pointer to interrupt an existing mapping." - address and subflow management:: MPTCP uses different addresses and + address and subflow management: MPTCP uses different addresses and allows a host to announce these addresses as part of the protocol. [RFC6897] says "An application should be able to restrict MPTCP to binding to a given set of addresses." and thus allows applications to limit the set of addresses that are being used by MPTCP. Further, "An application should be able to obtain information on the pairs of addresses used by the MPTCP subflows.". 3.3. Primitives Provided by SCTP Section 1.1 of [RFC4960] lists limitations of TCP that SCTP removes. @@ -390,64 +391,85 @@ messages, while reliably transferred, do not require to be in order unless the application wants it; 3) multi-homing is supported. In SCTP, connections are called "association" and they can be between not only two (as in TCP) but multiple addresses at each endpoint. Section 10 of [RFC4960] further specifies the interaction with the application (which RFC [RFC4960] calls the "Upper Layer Protocol" (ULP)). It is assumed that the Operating System provides a means for SCTP to asynchronously signal the application; the primitives representing such signals are called 'events' in this section. Here, - we describe the relevant primitives. + we describe the relevant primitives. In addition to the abstract API + described in Section 10 of [RFC4960], an extension to the socket API + is described in [RFC6458] covering the functionality of the base + protocol specified in [RFC4960] and its extensions specified in + [RFC3758], [RFC4895], and [RFC5061]. For the protocol extensions + specified in [RFC6525], [RFC6951], [RFC7053], [RFC7496], and + [RFC7829] the corresponding extensions of the socket API are + specified in these protocol specifications. The functionality + exposed to the ULP through this socket API is considered here in + addition to the abstract API specified in Section 10 of [RFC4960]. Initialize: Initialize creates a local SCTP instance that it binds to a set of local addresses (and, if provided, port number). Initialize needs to be called only once per set of local addresses. Associate: This creates an association (the SCTP equivalent of a connection) between the local SCTP instance and a remote SCTP instance. Most primitives are associated with a specific association, which is assumed to first have been created. Associate can return a list of destination transport addresses so that multiple paths can later be used. One of the returned sockets will be selected by the local endpoint as default primary path for sending SCTP packets to this peer, but this choice can be changed by the application using the list of destination addresses. Associate is also given the number of outgoing streams to request and optionally returns the number of outgoing streams - negotiated. + negotiated. An optional parameter of 32-bits, the adaptation + layer indication, can be provided, as specified in [RFC5061]. If + the extension specified in [RFC4895] is used, the chunk types + required to be sent authenticated by the peer can be provided. Send: This sends a message of a certain length in bytes over an association. A number can be provided to later refer to the correct message when reporting an error, and a stream id is provided to specify the stream to be used inside an association (we consider this as a mandatory parameter here for simplicity: if - not provided, the stream id defaults to 0). An optional maximum - life time can specify the time after which the message should be - discarded rather than sent. A choice (advisory, i.e. not - guaranteed) of the preferred path can be made by providing a - socket, and the message can be delivered out-of-order if the - unordered flag is set. Another advisory flag indicates whether - the application prefers to avoid bundling user data with other - outbound DATA chunks (i.e., in the same packet). A payload + not provided, the stream id defaults to 0). A condition to + abandon the message can be specified (for example limiting the + number of retransmissions or the lifetime of the user message). + This allows to control the partial reliability extension specified + in [RFC3758] and [RFC7496]. An optional maximum life time can + specify the time after which the message should be discarded + rather than sent. A choice (advisory, i.e. not guaranteed) of the + preferred path can be made by providing a socket, and the message + can be delivered out-of-order if the unordered flag is set. An + advisory flag indicates that the peer should not delay the + acknowledgement of the user message provided by making use of the + I-bit specified in [RFC7053]. Another advisory flag indicates + whether the application prefers to avoid bundling user data with + other outbound DATA chunks (i.e., in the same packet). A payload protocol-id can be provided to pass a value that indicates the - type of payload protocol data to the peer. + type of payload protocol data to the peer. If the extension + specified in [RFC4895] is used, the key identifier used for + authenticating the DATA chunks can be provided. Receive: Messages are received from an association, and optionally a stream within the association, with their size returned. The application is notified of the availability of data via a DATA ARRIVE notification. If the sender has included a payload protocol-id, this value is also returned. If the received message is only a partial delivery of a whole message, a partial flag will indicate so, in which case the stream id and a stream sequence - number are provided to the application. + number are provided to the application. A delivery number lets + the application detect reordering. Shutdown: This primitive gracefully closes an association, reliably delivering any data that has already been handed over to SCTP. A return code informs about success or failure of this procedure. Abort: This ungracefully closes an association, by discarding any locally queued data and informing the peer that the association was aborted. Optionally, an abort reason to be passed to the peer may be provided by the application. A return code informs about success or failure of this procedure. @@ -456,185 +478,269 @@ enable/disable heartbeats and optionally specify a heartbeat frequency as well as requesting a single heartbeat to be carried out upon a function call, with a notification about success or failure of transmitting the HEARTBEAT chunk to the destination. Set Protocol Parameters: This allows to set values for protocol parameters per association; for some parameters, a setting can be made per socket. The set listed in [RFC4960] is: RTO.Initial; RTO.Min; RTO.Max; Max.Burst; RTO.Alpha; RTO.Beta; Valid.Cookie.Life; Association.Max.Retrans; Path.Max.Retrans; - Max.Init.Retransmits; HB.interval; HB.Max.Burst. + Max.Init.Retransmits; HB.interval; HB.Max.Burst. In addition to + these, the Quick Failover Algorithm specified in [RFC7829] can be + controlled by the PotentiallyFailed.Max.Retrans and + Primary.Switchover.Max.Retrans parameter. A remote UDP + encapsulation port can be set for using UDP encapsulation as + specified in [RFC6951]. Set Primary: This allows to set a new primary default path for an association by providing a socket. Optionally, a default source address to be used in IP datagrams can be provided. + Set / Get Authentication Parameters: This allows an endpoint to add/ + remove key material to/from an association. In addition, the + chunk types being authenticated can be queried. This is provided + by the protocol extension defined in [RFC4895]. + + Change Local Address / Set Peer Primary: This allows an endpoint to + add/remove local addresses to/from an association. In addition, + the peer can be given a hint which address to use as the primary + address. This is provided by the protocol extension defined in + [RFC5061]. + + Add / Reset Streams, Reset Association: This allows an endpoint to + add streams to an existing association or or to reset them + individually. Additionally, the association can be reset. This + is provided by the protocol extension defined in [RFC6525]. + Status: The 'Status' primitive returns a data block with information about a specified association, containing: association connection state; socket list; destination transport address reachability states; current receiver window size; current congestion window sizes; number of unacknowledged DATA chunks; number of DATA chunks pending receipt; primary path; most recent SRTT on primary path; RTO on primary path; SRTT and RTO on other destination addresses. COMMUNICATION UP notification: When a lost communication to an endpoint is restored or when SCTP becomes ready to send or receive user messages, this notification informs the application process about the affected association, the type of event that has occurred, the complete set of sockets of the peer, the maximum number of allowed streams and the inbound stream count (the number of streams the peer endpoint has requested). DATA ARRIVE notification: When a message is ready to be retrieved via the Receive primitive, the application is informed by this notification. - SEND FAILURE notification / Receive Unsent Message - / Receive Unacknowledged Message: - When a message cannot be delivered via an association, the sender - can be informed about it and learn whether the message has just - not been acknowledged or (e.g. in case of lifetime expiry) if it - has not even been sent. + SEND FAILURE notification / Receive Unsent Message / Receive + Unacknowledged Message: When a message cannot be delivered via an + association, the sender can be informed about it and learn whether + the message has just not been acknowledged or (e.g. in case of + lifetime expiry) if it has not even been sent. NETWORK STATUS CHANGE notification: The NETWORK STATUS CHANGE notification informs the application about a socket becoming active/inactive. COMMUNICATION LOST notification: When SCTP loses communication to an endpoint (e.g. via Heartbeats or excessive retransmission) or detects an abort, this notification informs the application process of the affected association and the type of event (failure OR termination in response to a shutdown or abort request). SHUTDOWN COMPLETE notification: When SCTP completes the shutdown procedures, this notification is passed to the upper layer, informing it about the affected assocation. -3.3.1. Excluded Primitives + AUTHENICATION notification: When SCTP wants to notify the upper + layer regarding the key management related to the extension + defined in [RFC4895], this notification is passed to the upper + layer. + + ADAPTATION LAYER INDICATION notification: When SCTP completes the + association setup and the peer provided an adaptation layer + indication, this is passed to the upper layer. This extension is + defined in [RFC5061] and [RFC6458]. + + STREAM RESET notification: When SCTP completes the procedure for + resetting streams as specified in [RFC6525], this notification is + passed to the upper layer, informing it about the result. + + ASSOCIATION RESET notification: When SCTP completes the association + reset procedure as specified in [RFC6525], this notification is + passed to the upper layer, informing it about the result. + + STREAM CHANGE notification: When SCTP completes the procedure used + to increase the number of streams as specified in [RFC6525], this + notification is passed to the upper layer, informing it about the + result. + +3.3.1. Excluded Primitives or Parameters The 'Receive' primitive can return certain additional information, but this is optional to implement and therefore not considered. With a COMMUNICATION LOST notification, some more information may optionally be passed to the application (e.g., identification to retrieve unsent and unacknowledged data). SCTP "can invoke" a COMMUNICATION ERROR notification and "may send" a RESTART notification, making these two notifications optional to implement. The list provided under 'Status' includes "etc", indicating that more information could be provided. The primitive 'Get SRTT Report' returns information that is included in the information that 'Status' provides and is therefore not discussed. Similarly, 'Set Failure Threshold' sets only one out of various possible parameters included in 'Set Protocol Parameters'. The 'Destroy SCTP Instance' API function was excluded: it erases the SCTP instance that was created by 'Initialize', but is not a Primitive as defined in this document because it does not relate to a Transport Service Feature. +3.4. Primitives Provided by UDP and UDP-Lite + + The primitives provided by UDP and UDP-Lite are described in [FJ16]. + 4. Pass 2 This pass categorizes the primitives from pass 1 based on whether they relate to a connection or to data transmission. Primitives are - presented following the nomenclature: + presented following the nomenclature "CATEGORY.[SUBCATEGORY].PRIMITIVENAME.PROTOCOL". The CATEGORY can be CONNECTION or DATA. Within the CONNECTION category, ESTABLISHMENT, AVAILABILITY, MAINTENANCE and TERMINATION subcategories can be considered. The DATA category does not have any SUBCATEGORY (as of - now). A connection is a general protocol-independent concept and - refers to, e.g., TCP connections (identifiable by a unique pair of IP - addresses and TCP port numbers) as well as SCTP associations - (identifiable by multiple IP address and port number pairs). + now). The PROTOCOL name "UDP(-Lite)" is used when primitives are + equivalent for UDP and UDP-Lite; the PROTOCOL name "TCP" refers to + both TCP and MPTCP. We present "connection" as a general protocol- + independent concept and use it to refer to, e.g., TCP connections + (identifiable by a unique pair of IP addresses and TCP port numbers), + SCTP associations (identifiable by multiple IP address and port + number pairs), as well UDP and UDP-Lite connections (identifiable by + a unique socket pair). Some minor details are omitted for the sake of generalization -- e.g., SCTP's 'close' [RFC4960] returns success or failure, whereas this is not described in the same way for TCP in [RFC0793], but this detail plays no significant role for the primitives provided by either TCP or SCTP. The TCP 'send' and 'receive' primitives include usage of an "URGENT" mechanism. This mechanism is required to implement the "synch signal" used by telnet [RFC0854], but SHOULD NOT be used by new applications [RFC6093]. Because pass 2 is meant as a basis for the creation of TAPS systems, the "URGENT" mechanism is excluded. This also concerns the notification "Urgent pointer advance" in the ERROR_REPORT described in Section 4.2.4.1 of [RFC1122]. 4.1. CONNECTION Related Primitives ESTABLISHMENT: Active creation of a connection from one transport endpoint to one or more transport endpoints. + Interfaces to UDP and UDP-Lite allow both connection-oriented and + connection-less usage of the API [I-D.ietf-tsvwg-rfc5405bis] o CONNECT.TCP: Pass 1 primitive / event: 'open' (active) or 'open' (passive) with socket, followed by 'send' Parameters: 1 local IP address (optional); 1 destination transport address (for active open; else the socket and the local IP address of the succeeding incoming connection request will be maintained); timeout (optional); options (optional) Comments: If the local IP address is not provided, a default choice will automatically be made. The timeout can also be a retransmission count. The options are IP options to be used on all segments of the connection. At least the Source Route option is mandatory for TCP to provide. o CONNECT.SCTP: Pass 1 primitive / event: 'initialize', followed by 'associate' Parameters: list of local SCTP port number / IP address pairs - (initialize); 1 socket; outbound stream count + (initialize); 1 socket; outbound stream count; adaptation layer + indication; chunk types required to be authenticated Returns: socket list Comments: 'initialize' needs to be called only once per list of local SCTP port number / IP address pairs. One socket will automatically be chosen; it can later be changed in MAINTENANCE. - o Disable-MPTCP.MPTCP: - Pass 1 primitive / event: 'open' (active) or 'open' (passive) - Parameters: one boolean value - Comments: MPTCP is by default enabled on all TCP connections. - However, an application is still able to disable MPTCP for a - particular connection or socket prior to the CONNECT.TCP and - LISTEN.TCP primitives. + o CONNECT.MPTCP: + This is similar to CONNECT.TCP except for one additional boolean + parameter that allows to enable or disable MPTCP for a particular + connection or socket (default: enabled). + + o CONNECT.UDP(-Lite): + Pass 1 primitive / event: 'connect' followed by 'send'. + Parameters: 1 local IP address (default (ANY), or specified); 1 + destination transport address; 1 local port (default (OS chooses), + or specified); 1 destination port (default (OS chooses), or + specified). + Comments: Associates a transport address creating a UDP(-Lite) + socket connection. This can be called again with a new transport + address to create a new connection. The CONNECT function allows + an application to receive errors from messages sent to a transport + address. AVAILABILITY: Preparing to receive incoming connection requests. o LISTEN.TCP: Pass 1 primitive / event: 'open' (passive) Parameters: 1 local IP address (optional); 1 socket (optional); timeout (optional) Comments: if the socket and/or local IP address is provided, this waits for incoming connections from only and/or to only the provided address. Else this waits for incoming connections without this / these constraint(s). ESTABLISHMENT can later be performed with 'send'. o LISTEN.SCTP: Pass 1 primitive / event: 'initialize', followed by 'COMMUNICATION - UP' notification + UP' notification and possibly 'ADAPTATION LAYER' notification Parameters: list of local SCTP port number / IP address pairs (initialize) - Returns: socket list; outbound stream count; inbound stream count + Returns: socket list; outbound stream count; inbound stream count; + adaptation layer indication; chunks required to be authenticated Comments: initialize needs to be called only once per list of local SCTP port number / IP address pairs. COMMUNICATION UP can also follow a COMMUNICATION LOST notification, indicating that the - lost communication is restored. + lost communication is restored. If the peer has provided an + adaptation layer indication, an 'ADAPTATION LAYER' notification is + issued. + + o LISTEN.MPTCP: + This is similar to LISTEN.TCP except for one additional boolean + parameter that allows to enable or disable MPTCP for a particular + connection or socket (default: enabled). + + o LISTEN.UDP(-Lite): + Pass 1 primitive / event: 'receive'. + Parameters: 1 local IP address (default (ANY), or specified); 1 + destination transport address; local port (default (OS chooses), + or specified); destination port (default (OS chooses), or + specified). + Comments: The receive function registers the application to listen + for incoming UDP(-Lite) datagrams at an endpoint. MAINTENANCE: Adjustments made to an open connection, or notifications about it. These are out-of-band messages to the protocol that can be issued at any time, at least after a connection has been established and before it has been terminated (with one exception: CHANGE-TIMEOUT.TCP can - only be issued when DATA.SEND.TCP is called). + only be issued for an open connection when DATA.SEND.TCP is called). + In some cases, these primitives can also be immediately issued during + ESTABLISHMENT or AVAILABILITY, without waiting for the connection to + be opened (e.g. CHANGE-TIMEOUT.TCP can be done using TCP's 'open' + primitive). For UDP and UDP-Lite, these functions may establish a + setting per connection, but may also be changed per datagram message. o CHANGE-TIMEOUT.TCP: - - Pass 1 primitive / event: 'send' combined with unspecified control - of per-connection state variables + Pass 1 primitive / event: 'open' or 'send' combined with + unspecified control of per-connection state variables Parameters: timeout value (optional); ADV_UTO (optional); boolean UTO_ENABLED (optional, default false); boolean CHANGEABLE (optional, default true) Comments: when sending data, an application can adjust the connection's timeout value (time after which the connection will be aborted if data could not be delivered). If UTO_ENABLED is true, the user timeout value (or, if provided, the value ADV_UTO) will be advertised for the TCP on the other side of the connection to adapt its own user timeout accordingly. UTO_ENABLED controls whether the UTO option is enabled for a connection. This applies @@ -654,106 +760,244 @@ Association.Max.Retrans defines after how many unsuccessful heartbeats the connection will be terminated; thus these two primitives / parameters together can yield a similar behavior to CHANGE-TIMEOUT.TCP. o DISABLE-NAGLE.TCP: Pass 1 primitive / event: not specified Parameters: one boolean value Comments: the Nagle algorithm delays data transmission to increase the chance to send a full-sized segment. An application must be - able to disable this algorithm for a connection. This is related - to the no-bundle flag in DATA.SEND.SCTP. + able to disable this algorithm for a connection. o REQUESTHEARTBEAT.SCTP: Pass 1 primitive / event: 'Request HeartBeat' Parameters: socket Returns: success or failure Comments: requests an immediate heartbeat on a path, returning success or failure. o SETPROTOCOLPARAMETERS.SCTP: Pass 1 primitive / event: 'Set Protocol Parameters' Parameters: RTO.Initial; RTO.Min; RTO.Max; Max.Burst; RTO.Alpha; RTO.Beta; Valid.Cookie.Life; Association.Max.Retrans; - Path.Max.Retrans; Max.Init.Retransmits; HB.interval; HB.Max.Burst + Path.Max.Retrans; Max.Init.Retransmits; HB.interval; HB.Max.Burst; + PotentiallyFailed.Max.Retrans; Primary.Switchover.Max.Retrans; + Remote.UDPEncapsPort. o SETPRIMARY.SCTP: Pass 1 primitive / event: 'Set Primary' Parameters: socket Returns: result of attempting this operation Comments: update the current primary address to be used, based on the set of available sockets of the association. + o SETPEERPRIMARY.SCTP: + Pass 1 primitive / event: Change Local Address / Set Peer Primary + Parameters: local IP address + Comments: this is only advisory for the peer. + + o SETAUTH.SCTP: + Pass 1 primitive / event: Set / Get Authentication Parameters + Parameters: key_id, key, hmac_id + + o GETAUTH.SCTP: + Pass 1 primitive / event: Set / Get Authentication Parameters + Parameters: key_id, chunk_list + + o RESETSTREAM.SCTP: + Pass 1 primitive / event: Add / Reset Streams, Reset Association + Parameters: sid, direction + + o RESETSTREAM-EVENT.SCTP: + Pass 1 primitive / event: STREAM RESET notification + Parameters: information about the result of RESETSTREAM.SCTP. + Comments: This is issued when the procedure for resetting streams + has completed. + + o RESETASSOC.SCTP: + Pass 1 primitive / event: Add / Reset Streams, Reset Association + Parameters: information related to the extension defined in + [RFC3260]. + + o RESETASSOC-EVENT.SCTP: + Pass 1 primitive / event: ASSOCIATION RESET notification + Parameters: information about the result of RESETASSOC.SCTP. + Comments: This is issued when the procedure for resetting an + association has completed. + + o ADDSTREAM.SCTP: + Pass 1 primitive / event: Add / Reset Streams, Reset Association + Parameters: number if outgoing and incoming streams to be added + + o ADDSTREAM-EVENT.SCTP: + Pass 1 primitive / event: STREAM CHANGE notification + Parameters: information about the result of ADDSTREAM.SCTP. + + Comments: This is issued when the procedure for adding a stream + has completed. + o ERROR.TCP: Pass 1 primitive / event: 'ERROR_REPORT' Returns: reason (encoding not specified); subreason (encoding not specified) Comments: soft errors that can be ignored without harm by many applications; an application should be able to disable these notifications. The reported conditions include at least: ICMP error message arrived; Excessive Retransmissions. + o ERROR.UDP(-Lite): + Pass 1 primitive / event: 'ERROR_REPORT'. + Returns: Error report + Comments: This returns soft errors that may be ignored without + harm by many applications; An application must connect to be able + receive these notifications. + o STATUS.SCTP: Pass 1 primitive / event: 'Status' and 'NETWORK STATUS CHANGE' notification Returns: data block with information about a specified association, containing: association connection state; socket list; destination transport address reachability states; current receiver window size; current congestion window sizes; number of unacknowledged DATA chunks; number of DATA chunks pending receipt; primary path; most recent SRTT on primary path; RTO on primary path; SRTT and RTO on other destination addresses. The NETWORK STATUS CHANGE notification informs the application about a socket becoming active/inactive. o STATUS.MPTCP: Pass 1 primitive / event: not specified Returns: list of pairs of tuples of IP address and TCP port number of each subflow. The first of the pair is the local IP and port number, while the second is the remote IP and port number. - o CHANGE-DSCP.TCP: + o SET_DSCP.TCP: Pass 1 primitive / event: not specified Parameters: DSCP value - Comments: this allows an application to change the DSCP value. - For TCP this was originally specified for the TOS field [RFC1122], - which is here interpreted to refer to the DSField [RFC3260]. + Comments: this allows an application to change the DSCP value for + outgoing segments. For TCP this was originally specified for the + TOS field [RFC1122], which is here interpreted to refer to the + DSField [RFC3260]. + + o SET_DSCP.UDP(-Lite): + Pass 1 primitive / event: 'SET_DSCP' + Parameter: DSCP value + Comments: This allows an application to change the DSCP value for + outgoing UDP(-Lite) datagrams. [RFC7657] and + [I-D.ietf-tsvwg-rfc5405bis] provide current guidance on using this + value with UDP. o ADD_SUBFLOW.MPTCP: Pass 1 primitive / event: not specified Parameters: local IP address and optionally the local port number Comments: the application specifies the local IP address and port number that must be used for a new subflow. + o ADD_ADDR.SCTP: + Pass 1 primitive / event: Change Local Address / Set Peer Primary + Parameters: local IP address + o REM_SUBFLOW.MPTCP: Pass 1 primitive / event: not specified Parameters: local IP address, local port number, remote IP address, remote port number Comments: the application removes the subflow specified by the IP/ port-pair. The MPTCP implementation must trigger a removal of the subflow that belongs to this IP/port-pair. + o REM_ADDR.SCTP: + Pass 1 primitive / event: Change Local Address / Set Peer Primary + Parameters: local IP address + + o CHECKSUM.UDP: + Pass 1 primitive / event: 'DISABLE_CHECKSUM'. + Parameters: 0 when no checksum is used at sender, 1 for checksum + at sender (default). + + o CHECKSUM_REQUIRED.UDP: + Pass 1 primitive / event: 'REQUIRE_CHECKSUM'. + Parameter: 0 when checksum is required at receiver, 1 to allow + zero checksum at receiver (default). + + o SET_CHECKSUM_COVERAGE.UDP-Lite: + Pass 1 primitive / event: 'SET_CHECKSUM_COVERAGE'. + Parameters: Coverage length at sender (default maximum coverage) + + o SET_MIN_CHECKSUM_COVERAGE.UDP-Lite: + Pass 1 primitive / event: 'SET_MIN_COVERAGE'. + Parameter: Coverage length at receiver (default minimum coverage) + + o SET_DF.UDP(-Lite): + Pass 1 primitive event: 'SET_DF'. + Parameter: 0 when DF is not set (default), 1 when DF is set. + + o SET_TTL.UDP(-Lite) (IPV6_UNICAST_HOPS): + Pass 1 primitive / event: 'SET_TTL' and 'SET_IPV6_UNICAST_HOPS' + Parameters: IPv4 TTL value or IPv6 Hop Count value + Comments: This allows an application to change the IPv4 TTL of + IPv6 Hop count value for outgoing UDP(-Lite) datagrams. + + o GET_TTL.UDP(-Lite) (IPV6_UNICAST_HOPS): + Pass 1 primitive / event: 'GET_TTL' and 'GET_IPV6_UNICAST_HOPS' + Returns: IPv4 TTL value or IPv6 Hop Count value + Comments: This allows an application to read the the IPv4 TTL of + IPv6 Hop count value from a received UDP(-Lite) datagram. + + o SET_ECN.UDP(-Lite): + Pass 1 primitive / event: 'SET_ECN' + Parameters: ECN value + Comments: This allows a UDP(-Lite) application to set the ECN + codepoint field for outgoing UDP(-Lite) datagrams. + + o GET_ECN.UDP(-Lite): + Pass 1 primitive / event: 'GET_ECN' + Parameters: ECN value + Comments: This allows a UDP(-Lite) application to read the ECN + codepoint field from a received UDP(-Lite) datagram. + + o SET_IP_OPTIONS.UDP(-Lite): + Pass 1 primitive / event: 'SET_IP_OPTIONS' + Parameters: options + Comments: This allows a UDP(-Lite) application to set IP Options + for outgoing UDP(-Lite) datagrams. These options can at least be + the Source Route, Record Route, and Time Stamp option. + + o GET_IP_OPTIONS.UDP(-Lite): + Pass 1 primitive / event: 'GET_IP_OPTIONS' + Returns: options + Comments: This allows a UDP(-Lite) application to receive any IP + options that are contained in a received UDP(-Lite) datagram. + + o AUTHENTICATION_NOTIFICATION-EVENT.SCTP: + Pass 1 primitive / event: 'AUTHENTICATION notification' + Returns: information regarding key management. + TERMINATION: Gracefully or forcefully closing a connection, or being informed about this event happening. o CLOSE.TCP: Pass 1 primitive / event: 'close' Comments: this terminates the sending side of a connection after reliably delivering all remaining data. o CLOSE.SCTP: Pass 1 primitive / event: 'Shutdown' Comments: this terminates a connection after reliably delivering all remaining data. + o CLOSE.UDP(-Lite): + Pass 1 primitive event: 'CLOSE' + Comments: No further UDP(-Lite) datagrams are sent/received on + this connection. + o ABORT.TCP: Pass 1 primitive / event: 'abort' Comments: this terminates a connection without delivering remaining data and sends an error message to the other side. o ABORT.SCTP: Pass 1 primitive / event: 'abort' Parameters: abort reason to be given to the peer (optional) Comments: this terminates a connection without delivering remaining data and sends an error message to the other side. @@ -787,139 +1031,177 @@ o CLOSE-EVENT.SCTP: Pass 1 primitive / event: 'SHUTDOWN COMPLETE' event Comments: the application is informed that CONNECTION.TERMINATION.CLOSE.SCTP was successfully completed. 4.2. DATA Transfer Related Primitives All primitives in this section refer to an existing connection, i.e. a connection that was either established or made available for - receiving data. In addition to the listed parameters, all sending - primitives contain a reference to a data block and all receiving - primitives contain a reference to available buffer space for the - data. + receiving data (although this is optional for the primitives of UDP(- + Lite)). In addition to the listed parameters, all sending primitives + contain a reference to a data block and all receiving primitives + contain a reference to available buffer space for the data. o SEND.TCP: Pass 1 primitive / event: 'send' Parameters: timeout (optional) Comments: this gives TCP a data block for reliable transmission to the TCP on the other side of the connection. The timeout can be configured with this call whenever data are sent (see also CONNECTION.MAINTENANCE.CHANGE-TIMEOUT.TCP). o SEND.SCTP: Pass 1 primitive / event: 'Send' - Parameters: stream number; context (optional); life time - (optional); socket (optional); unordered flag (optional); no- - bundle flag (optional); payload protocol-id (optional) - Comments: this gives SCTP a data block for reliable transmission - to the SCTP on the other side of the connection (SCTP - association). The 'stream number' denotes the stream to be used. - The 'context' number can later be used to refer to the correct - message when an error is reported. The 'life time' specifies a - time after which this data block will not be sent. The 'socket' - can be used to state which path should be preferred, if there are - multiple paths available (see also - CONNECTION.MAINTENANCE.SETPRIMARY.SCTP). The data block can be - delivered out-of-order if the 'unordered flag' is set. The 'no- - bundle flag' can be set to indicate a preference to avoid + Parameters: stream number; context (optional); socket (optional); + unordered flag (optional); no-bundle flag (optional); payload + protocol-id (optional); pr-policy (optional) pr-value (optional); + sack-immediately flag (optional); key-id (optional) + Comments: this gives SCTP a data block for transmission to the + SCTP on the other side of the connection (SCTP association). The + 'stream number' denotes the stream to be used. The 'context' + number can later be used to refer to the correct message when an + error is reported. The 'socket' can be used to state which path + should be preferred, if there are multiple paths available (see + also CONNECTION.MAINTENANCE.SETPRIMARY.SCTP). The data block can + be delivered out-of-order if the 'unordered flag' is set. The + 'no-bundle flag' can be set to indicate a preference to avoid bundling. The 'payload protocol-id' is a number that will, if - provided, be handed over to the receiving application. + provided, be handed over to the receiving application. Using pr- + policy and pr-value the level of reliability can be controlled. + The sack-immediately flag can be used to indicate that the peer + should not delay the sending of a SACK corresponding to the + provided user message. If specified, the provided key-id is used + for authenticating the user message. + + o SEND.UDP(-Lite): + Pass 1 primitive / event: 'SEND' + Parameters: IP Address and Port Number of the destination endpoint + (optional if connected). + Comments: This provides a message for unreliable transmission + using UDP(-Lite) to the specified transport address. IP address + and Port may be omitted for connected UDP(-Lite) sockets. All + CONNECTION.MAINTENANCE.SET_*.UDP(-Lite) primitives apply per + message sent. o RECEIVE.TCP: Pass 1 primitive / event: 'receive'. o RECEIVE.SCTP: Pass 1 primitive / event: 'DATA ARRIVE' notification, followed by 'Receive' Parameters: stream number (optional) Returns: stream sequence number (optional), partial flag (optional) Comments: if the 'stream number' is provided, the call to receive only receives data on one particular stream. If a partial message arrives, this is indicated by the 'partial flag', and then the 'stream sequence number' must be provided such that an application can restore the correct order of data blocks that comprise an - entire message. + entire message. Additionally, a delivery number lets the + application detect reordering. + + o RECEIVE.UDP(-Lite): + Pass 1 primitive / event: 'RECEIVE', + Parameters: Buffer for received datagram. + Comments: All CONNECTION.MAINTENANCE.GET_*.UDP(-Lite) primitives + apply per message received. o SENDFAILURE-EVENT.SCTP: Pass 1 primitive / event: 'SEND FAILURE' notification, optionally followed by 'Receive Unsent Message' or 'Receive Unacknowledged Message' Returns: cause code; context; unsent or unacknowledged message (optional) Comments: 'cause code' indicates the reason of the failure, and 'context' is the context number if such a number has been provided in DATA.SEND.SCTP, for later use with 'Receive Unsent Message' or 'Receive Unacknowledged Message', respectively. These primitives can be used to retrieve the complete unsent or unacknowledged message if desired. + o SEND_FAILURE.UDP(-Lite): + Pass 1 primitive / event: 'SEND' + Comment: This may be used to probe for the effective PMTU when + using in combination with the 'MAINTENANCE.SET_DF' primitive. + 5. Pass 3 This section presents the superset of all transport service features in all protocols that were discussed in the preceding sections, based on the list of primitives in pass 2 but also on text in pass 1 to include features that can be configured in one protocol and are - static properties in another. Again, some minor details are omitted - for the sake of generalization -- e.g., TCP may provide various - different IP options, but only source route is mandatory to - implement, and this detail is not visible in the Pass 3 feature - "Specify IP Options". - - [AUTHOR'S NOTE: the list here looks pretty similar to the list in - pass 2 for now. This will change as more protocols are added. For - example, when we add UDP, we will find that UDP does not do - congestion control, which is relevant to the application using it. - This will have to be reflected in pass 1 and pass 2, only for UDP. - In pass 3, we can then derive "no congestion control" as a transport - service feature of UDP; however, since it would be strange to call - the lack of congestion control a feature, the natural outcome is then - to list "congestion control" as a feature of TCP and SCTP.] + static properties in another (congestion control, for example). + Again, some minor details are omitted for the sake of generalization + -- e.g., TCP may provide various different IP options, but only + source route is mandatory to implement, and this detail is not + visible in the Pass 3 feature "Specify IP Options". 5.1. CONNECTION Related Transport Service Features ESTABLISHMENT: Active creation of a connection from one transport endpoint to one or more transport endpoints. o Connect - Protocols: TCP, SCTP + Protocols: TCP, SCTP, UDP(-Lite) - o Specify IP Options + o Specify which IP Options must always be used Protocols: TCP o Request multiple streams Protocols: SCTP o Obtain multiple sockets Protocols: SCTP o Disable MPTCP - Protocols: MPTCP/TCP + Protocols: MPTCP + + o Specify which chunk types must always be authenticated + Protocols: SCTP + Comments: DATA, ACK etc. are different 'chunks' in SCTP; one or + more chunks may be included in a single packet. + + o Indicate an Adaptation Layer (via an adaptation code point) + Protocols: SCTP AVAILABILITY: Preparing to receive incoming connection requests. o Listen, 1 specified local interface - Protocols: TCP, SCTP + Protocols: TCP, SCTP, UDP(-Lite) o Listen, N specified local interfaces - Protocols: SCTP + Protocols: SCTP, UDP(-Lite) o Listen, all local interfaces - Protocols: TCP, SCTP + Protocols: TCP, SCTP, UDP(-Lite) o Obtain requested number of streams Protocols: SCTP + o Specify which IP Options must always be used + Protocols: TCP + + o Disable MPTCP + Protocols: MPTCP + + o Specify which chunk types must always be authenticated + Protocols: SCTP + Comments: DATA, ACK etc. are different 'chunks' in SCTP; one or + more chunks may be included in a single packet. + + o Indicate an Adaptation Layer (via an adaptation code point) + Protocols: SCTP + MAINTENANCE: Adjustments made to an open connection, or notifications about it. NOTE: all features except "set primary path" in this category apply to one out of multiple possible paths (identified via sockets) in SCTP, whereas TCP uses only one path (one socket). o Change timeout for aborting connection (using retransmit limit or time value) Protocols: TCP, SCTP @@ -931,62 +1213,129 @@ Protocols: TCP, SCTP Comments: This is not specified in [RFC4960] but in [RFC6458]. o Request an immediate heartbeat, returning success/failure Protocols: SCTP o Set protocol parameters Protocols: SCTP SCTP parameters: RTO.Initial; RTO.Min; RTO.Max; Max.Burst; RTO.Alpha; RTO.Beta; Valid.Cookie.Life; Association.Max.Retrans; - Path.Max.Retrans; Max.Init.Retransmits; HB.interval; HB.Max.Burst - Comments: in future versions of this document, it might make sense - to split out some of these parameters -- e.g., if a different - protocol provides means to adjust the RTO calculation there could - be a common feature for them called "adjust RTO calculation". + Path.Max.Retrans; Max.Init.Retransmits; HB.interval; HB.Max.Burst; + PotentiallyFailed.Max.Retrans; Primary.Switchover.Max.Retrans; + Remote.UDPEncapsPort + Comments: as transport layer features from other protocols are + added, it might make sense to separate out some of these + parameters -- e.g., if a different protocol provides means to + adjust the RTO calculation there could be a common feature for + them called "adjust RTO calculation". o Notification of Excessive Retransmissions (early warning below abortion threshold) Protocols: TCP o Notification of ICMP error message arrival - Protocols: TCP + Protocols: TCP, UDP(-Lite) - o Status (query or notification) + o Obtain status (query or notification) Protocols: SCTP, MPTCP SCTP parameters: association connection state; socket list; socket reachability states; current receiver window size; current congestion window sizes; number of unacknowledged DATA chunks; number of DATA chunks pending receipt; primary path; most recent SRTT on primary path; RTO on primary path; SRTT and RTO on other destination addresses; socket becoming active / inactive MPTCP parameters: subflow-list (identified by source-IP; source- Port; destination-IP; destination-Port) + o Change authentication parameters + Protocols: SCTP + + o Obtain authentication information + Protocols: SCTP + o Set primary path Protocols: SCTP - o Change DSCP - Protocols: TCP - Comments: This is described to be changeable for SCTP too in - [RFC6458]. + o Reset Stream + Protocols: SCTP + + o Notification of Stream Reset + Protocols: STCP + + o Reset Association + Protocols: SCTP + + o Notification of Association Reset + Protocols: STCP + + o Add Streams + Protocols: SCTP + + o Notification of Added Stream + Protocols: STCP + + o Set peer primary path + Protocols: SCTP + + o Specify DSCP field + Protocols: TCP, SCTP, UDP(-Lite) o Add subflow Protocols: MPTCP MPTCP Parameters: source-IP; source-Port; destination-IP; destination-Port o Remove subflow Protocols: MPTCP MPTCP Parameters: source-IP; source-Port; destination-IP; destination-Port + o Add local address + Protocols: SCTP + + o Remove local address + Protocols: SCTP + + o Disable checksum when sending + Protocols: UDP + + o Disable checksum requirement when receiving + Protocols: UDP + + o Specify checksum coverage used by the sender + Protocols: UDP-Lite + + o Specify minimum checksum coverage required by receiver + Protocols: UDP-Lite + + o Specify DF field + Protocols: UDP(-Lite) + + o Specify TTL/Hop count field + Protocols: UDP(-Lite) + + o Obtain TTL/Hop count field + Protocols: UDP(-Lite) + + o Specify ECN field + Protocols: UDP(-Lite) + + o Obtain ECN field + Protocols: UDP(-Lite) + + o Specify IP Options + Protocols: UDP(-Lite) + + o Obtain IP Options + Protocols: UDP(-Lite) + TERMINATION: Gracefully or forcefully closing a connection, or being informed about this event happening. o Close after reliably delivering all remaining data, causing an event informing the application on the other side Protocols: TCP, SCTP Comments: A TCP endpoint locally only closes the connection for sending; it may still receive data afterwards. @@ -1008,194 +1357,275 @@ All features in this section refer to an existing connection, i.e. a connection that was either established or made available for receiving data. Reliable data transfer entails delay -- e.g. for the sender to wait until it can transmit data, or due to retransmission in case of packet loss. 5.2.1. Sending Data All features in this section are provided by DATA.SEND from pass 2. DATA.SEND is given a data block from the application, which we here - call a "message". + call a "message" if the beginning and end of the data block can be + identified at the receiver, and "data" otherwise. - o Reliably transfer data - Protocols: TCP, SCTP + o Reliably transfer data, with congestion control + Protocols: TCP - o Message identification + o Reliably transfer a message, with congestion control Protocols: SCTP - o Choice of stream + o Unreliably transfer a message, with congestion control Protocols: SCTP - o Choice of path (destination address) + o Unreliably transfer a message, without congestion control + Protocols: UDP(-Lite) + + o Configurable Message Reliability Protocols: SCTP - o Message lifetime + o Choice of stream + Protocols: SCTP + + o Choice of path (destination address) Protocols: SCTP o Choice between unordered (potentially faster) or ordered delivery of messages Protocols: SCTP o Request not to bundle messages Protocols: SCTP o Specifying a "payload protocol-id" (handed over as such by the receiver) Protocols: SCTP + o Specifying a key id to be used to authenticate a message + Protocols: SCTP + + o Request not to delay the acknowledgement (SACK) of a message + Protocols: SCTP + 5.2.2. Receiving Data All features in this section are provided by DATA.RECEIVE from pass - 2. DATA.RECEIVE fills a buffer provided to the application, with - what we here call a "message". + 2. DATA.RECEIVE fills a buffer provided by the application, with + what we here call a "message" if the beginning and end of the data + block can be identified at the receiver, and "data" otherwise. o Receive data - Protocols: TCP, SCTP + Protocols: TCP + + o Receive a message + Protocols: SCTP, UDP(-Lite) o Choice of stream to receive from Protocols: SCTP - o Message identification - Protocols: SCTP - Comments: In SCTP, this is optionally achieved with a "stream - sequence number". The stream sequence number is always provided - in case of partial message arrival. - o Information about partial message arrival Protocols: SCTP Comments: In SCTP, partial messages are combined with a stream sequence number so that the application can restore the correct order of data blocks an entire message consists of. + o Obtain a message delivery number + Protocols: SCTP + Comments: This number can let applications detect and, if desired, + correct reordering. + 5.2.3. Errors This section describes sending failures that are associated with a specific call to DATA.SEND from pass 2. o Notification of unsent messages - Protocols: SCTP + Protocols: SCTP, UDP(-Lite) o Notification of unacknowledged messages Protocols: SCTP 6. Acknowledgements The authors would like to thank (in alphabetical order) Bob Briscoe, - David Hayes, Gorry Fairhurst, Karen Nielsen and Joe Touch for - providing valuable feedback on this document. Special thanks goes - also to Christoph Paasch for providing input related to Multipath + Gorry Fairhurst, David Hayes, Tom Jones, Karen Nielsen and Joe Touch + for providing valuable feedback on this document. We especially + thank to Christoph Paasch for providing input related to Multipath TCP. This work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 644334 (NEAT). The views expressed are solely those of the author(s). 7. IANA Considerations XX RFC ED - PLEASE REMOVE THIS SECTION XXX This memo includes no request to IANA. 8. Security Considerations Security will be considered in future versions of this document. 9. References 9.1. Normative References + [I-D.ietf-tsvwg-rfc5405bis] + Eggert, L., Fairhurst, G., and G. Shepherd, "UDP Usage + Guidelines", draft-ietf-tsvwg-rfc5405bis-07 (work in + progress), November 2015. + [RFC0793] Postel, J., "Transmission Control Protocol", STD 7, RFC 793, DOI 10.17487/RFC0793, September 1981, . [RFC1122] Braden, R., Ed., "Requirements for Internet Hosts - - Communication Layers", STD 3, RFC 1122, - DOI 10.17487/RFC1122, October 1989, + Communication Layers", STD 3, RFC 1122, DOI 10.17487/ + RFC1122, October 1989, . [RFC4960] Stewart, R., Ed., "Stream Control Transmission Protocol", RFC 4960, DOI 10.17487/RFC4960, September 2007, . [RFC5482] Eggert, L. and F. Gont, "TCP User Timeout Option", RFC 5482, DOI 10.17487/RFC5482, March 2009, . 9.2. Informative References - [FA15] Fairhurst, Ed., G., Trammell, Ed., B., and M. Kuehlewind, + [FA16] Fairhurst, Ed., G., Trammell, Ed., B., and M. Kuehlewind, Ed., "Services provided by IETF transport protocols and - congestion control mechanisms", Internet-draft draft- - fairhurst-taps-transports-08.txt, December 2015. + congestion control mechanisms", + draft-ietf-taps-transports-12.txt (work in progress), + October 2016. + + [FJ16] Fairhurst, G. and T. Jones, "Features of the User Datagram + Protocol (UDP) and Lightweight UDP (UDP-Lite) Transport + Protocols", draft-fairhurst-taps-transports-usage-udp-03 + (work in progress), October 2016. [RFC0854] Postel, J. and J. Reynolds, "Telnet Protocol - Specification", STD 8, RFC 854, DOI 10.17487/RFC0854, May - 1983, . + Specification", STD 8, RFC 854, DOI 10.17487/RFC0854, + May 1983, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate - Requirement Levels", BCP 14, RFC 2119, - DOI 10.17487/RFC2119, March 1997, + Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/ + RFC2119, March 1997, . [RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition of Explicit Congestion Notification (ECN) to IP", RFC 3168, DOI 10.17487/RFC3168, September 2001, . [RFC3260] Grossman, D., "New Terminology and Clarifications for Diffserv", RFC 3260, DOI 10.17487/RFC3260, April 2002, . + [RFC3758] Stewart, R., Ramalho, M., Xie, Q., Tuexen, M., and P. + Conrad, "Stream Control Transmission Protocol (SCTP) + Partial Reliability Extension", RFC 3758, DOI 10.17487/ + RFC3758, May 2004, + . + [RFC3828] Larzon, L-A., Degermark, M., Pink, S., Jonsson, L-E., Ed., and G. Fairhurst, Ed., "The Lightweight User Datagram - Protocol (UDP-Lite)", RFC 3828, DOI 10.17487/RFC3828, July - 2004, . + Protocol (UDP-Lite)", RFC 3828, DOI 10.17487/RFC3828, + July 2004, . + + [RFC4895] Tuexen, M., Stewart, R., Lei, P., and E. Rescorla, + "Authenticated Chunks for the Stream Control Transmission + Protocol (SCTP)", RFC 4895, DOI 10.17487/RFC4895, + August 2007, . + + [RFC5061] Stewart, R., Xie, Q., Tuexen, M., Maruyama, S., and M. + Kozuka, "Stream Control Transmission Protocol (SCTP) + Dynamic Address Reconfiguration", RFC 5061, DOI 10.17487/ + RFC5061, September 2007, + . [RFC5461] Gont, F., "TCP's Reaction to Soft Errors", RFC 5461, DOI 10.17487/RFC5461, February 2009, . [RFC6093] Gont, F. and A. Yourtchenko, "On the Implementation of the TCP Urgent Mechanism", RFC 6093, DOI 10.17487/RFC6093, January 2011, . [RFC6182] Ford, A., Raiciu, C., Handley, M., Barre, S., and J. Iyengar, "Architectural Guidelines for Multipath TCP Development", RFC 6182, DOI 10.17487/RFC6182, March 2011, . [RFC6458] Stewart, R., Tuexen, M., Poon, K., Lei, P., and V. Yasevich, "Sockets API Extensions for the Stream Control - Transmission Protocol (SCTP)", RFC 6458, - DOI 10.17487/RFC6458, December 2011, + Transmission Protocol (SCTP)", RFC 6458, DOI 10.17487/ + RFC6458, December 2011, . + [RFC6525] Stewart, R., Tuexen, M., and P. Lei, "Stream Control + Transmission Protocol (SCTP) Stream Reconfiguration", + RFC 6525, DOI 10.17487/RFC6525, February 2012, + . + [RFC6824] Ford, A., Raiciu, C., Handley, M., and O. Bonaventure, "TCP Extensions for Multipath Operation with Multiple Addresses", RFC 6824, DOI 10.17487/RFC6824, January 2013, . [RFC6897] Scharf, M. and A. Ford, "Multipath TCP (MPTCP) Application Interface Considerations", RFC 6897, DOI 10.17487/RFC6897, March 2013, . + [RFC6951] Tuexen, M. and R. Stewart, "UDP Encapsulation of Stream + Control Transmission Protocol (SCTP) Packets for End-Host + to End-Host Communication", RFC 6951, DOI 10.17487/ + RFC6951, May 2013, + . + + [RFC7053] Tuexen, M., Ruengeler, I., and R. Stewart, "SACK- + IMMEDIATELY Extension for the Stream Control Transmission + Protocol", RFC 7053, DOI 10.17487/RFC7053, November 2013, + . + [RFC7414] Duke, M., Braden, R., Eddy, W., Blanton, E., and A. Zimmermann, "A Roadmap for Transmission Control Protocol - (TCP) Specification Documents", RFC 7414, - DOI 10.17487/RFC7414, February 2015, + (TCP) Specification Documents", RFC 7414, DOI 10.17487/ + RFC7414, February 2015, . + [RFC7496] Tuexen, M., Seggelmann, R., Stewart, R., and S. Loreto, + "Additional Policies for the Partially Reliable Stream + Control Transmission Protocol Extension", RFC 7496, + DOI 10.17487/RFC7496, April 2015, + . + + [RFC7657] Black, D., Ed. and P. Jones, "Differentiated Services + (Diffserv) and Real-Time Communication", RFC 7657, + DOI 10.17487/RFC7657, November 2015, + . + + [RFC7829] Nishida, Y., Natarajan, P., Caro, A., Amer, P., and K. + Nielsen, "SCTP-PF: A Quick Failover Algorithm for the + Stream Control Transmission Protocol", RFC 7829, + DOI 10.17487/RFC7829, April 2016, + . + Appendix A. Overview of RFCs used as input for pass 1 TCP: [RFC0793], [RFC1122], [RFC5482] MPTCP: [RFC6182], [RFC6824], [RFC6897] - SCTP: [RFC4960], planned: [RFC6458] + SCTP: RFCs without a socket API specification: [RFC3758], [RFC4895], + [RFC4960], [RFC5061]. RFCs that include a socket API + specification: [RFC6458], [RFC6525], [RFC6951], [RFC7053], + [RFC7496] [RFC7829]. + UDP(-Lite): See [FJ16] Appendix B. How to contribute This document is only concerned with transport service features that are explicitly exposed to applications via primitives. It also strictly follows RFC text: if a feature is truly relevant for an application, the RFCs better say so and in some way describe how to use and configure it. Thus, the approach to follow for contributing to this document is to identify the right RFCs, then analyze and process their text. @@ -1225,21 +1655,21 @@ parts from the relevant RFCs, then adjust terminology to match the terminology in Section 1 and adjust (shorten!) phrasing to match the general style of the document. Try to formulate everything as a primitive description to make the primitive description as complete as possible (e.g., the "SEND.TCP" primitive in pass 2 is explicitly described as reliably transferring data); if there is text that is relevant for the primitives presented in this pass but still does not fit directly under any primitive, use it as an introduction for your subsection. However, do note that document length is a concern and all the protocols and their services / features are already described - in [FA15]. + in [FA16]. Pass 2: The main goal of this pass is unification of primitives. As input, use your own text from Pass 1, no exterior sources. If you find that something is missing there, fix the text in Pass 1. The list in pass 2 is not done by protocol ("first protocol X, here are all the primitives; then protocol Y, here are all the primitives, ..") but by primitive ("primitive A, implemented this way in protocol X, this way in protocol Y, ..."). We want as many similar pass 2 primitives as possible. This can be achieved, for instance, by not always maintaining a 1:1 mapping between pass 1 and pass 2 @@ -1276,33 +1706,47 @@ Appendix C. Revision information XXX RFC-Ed please remove this section prior to publication. -00 (from draft-welzl-taps-transports): this now covers TCP based on all TCP RFCs (this means: if you know of something in any TCP RFC that you think should be addressed, please speak up!) as well as SCTP, exclusively based on [RFC4960]. We decided to also incorporate [RFC6458] for SCTP, but this hasn't happened yet. Terminology made - in line with [FA15]. Addressed comments by Karen Nielsen and Gorry + in line with [FA16]. Addressed comments by Karen Nielsen and Gorry Fairhurst; various other fixes. Appendices (TCP overview and how-to- contribute) added. -01: this now also covers MPTCP based on [RFC6182], [RFC6824] and [RFC6897]. + -02: included UDP, UDP-Lite, and all extensions of SCTPs. This + includes fixing the [RFC6458] omission from -00. + + TODO: security considerations (see review in ML); the "how to + contribute" section (which, at some point, should be updated to + reflect how the document WAS created, not how it SHOULD BE created) + still says "Experimental RFCs are excluded". This is wrong, and + accordingly, Experimental RFCs must also be considered - thus, TFO + (are there more Experimental ones for TCP?). Also, include LEDBAT. + SCTP: DSCP and SCTP_NODELAY (equivalent to Nagle) are missing in pass + 1 and 2. Are we missing more (DF, TTL, ..)? What about e.g. + "notification of ICMP error message arrival"? Also consider + draft-ietf-tsvwg-sctp-ndata. + Authors' Addresses Michael Welzl University of Oslo PO Box 1080 Blindern - Oslo N-0316 + Oslo, N-0316 Norway Phone: +47 22 85 24 20 Email: michawe@ifi.uio.no Michael Tuexen Muenster University of Applied Sciences Stegerwaldstrasse 39 Steinfurt 48565 Germany @@ -1301,18 +1745,17 @@ Phone: +47 22 85 24 20 Email: michawe@ifi.uio.no Michael Tuexen Muenster University of Applied Sciences Stegerwaldstrasse 39 Steinfurt 48565 Germany Email: tuexen@fh-muenster.de - Naeem Khademi University of Oslo PO Box 1080 Blindern - Oslo N-0316 + Oslo, N-0316 Norway Email: naeemk@ifi.uio.no