2024年6月13日发(作者：向景山)
Network Working Group K. Schneider
Request for Comments: 1963 S. Venters
Category: Informational ADTRAN, Inc.
August 1996
PPP Serial Data Transport Protocol (SDTP)
Status of This Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
Abstract
The Point-to-Point Protocol (PPP) [1] provides a standard method for
transporting multi-protocol datagrams over point-to-point links. PPP
defines an extensible Link Control Protocol, and proposes a family of
Network Control Protocols for establishing and configuring different
network-layer protocols.
This document describes a new Network level protocol (from the PPP
point of view), PPP Serial Data Transport Protocol, that provides
encapsulation and an associated control protocol for transporting
serial data streams over a PPP link. This protocol was developed for
the purpose of using PPP’s many features to provide a standard method
for synchronous data compression. The encapsulation uses a header
structure based on that of the ITU-T Recommendation V.120 [2].
Table of Contents
1. Introduction .......................................... 2
2. SDTP Packets .......................................... 3
2.1 Padding ......................................... 4
2.2 Packet Formats .................................. 4
3. Serial Data Control Protocol .......................... 11
4. SDCP Configuration Option Format ...................... 12
4.1 Packet-Format ................................... 13
4.2 Header-Type ..................................... 13
4.3 Length-Field-Present ............................ 14
4.4 Multi-Port ...................................... 14
4.5 Transport-Mode .................................. 15
4.6 Maximum-Frame-Size .............................. 16
4.7 Allow-Odd-Frames ................................ 16
4.8 FCS-Type ........................................ 17
4.9 Flow-Expiration-Time ............................ 18
SECURITY CONSIDERATIONS ...................................... 19
Schneider & Venters Informational [Page 1]
RFC 1963 PPP SDTP August 1996
REFERENCES ................................................... 19
CHAIR’S ADDRESS .............................................. 20
AUTHORS’ ADDRESSES ........................................... 20
1. Introduction
This document is a product of the TR30.1 ad hoc committee on
compression of synchronous data. It represents a component of a
proposal to use PPP to provide compression of synchronous data in
DSU/CSUs.
In addition to providing support for multi-protocol datagrams, the
Point-to-Point Protocol (PPP) [1] has defined an effective and robust
negotiating mechanism that can be used on point to point links. When
used in conjunction with the PPP Compression Control Protocol [3] and
one of the PPP Compression Protocols [4-10], PPP provides an
interoperable method of employing data compression on a point-to-
point link.
This document provides a PPP encapsulation for serial data,
specifying a transport protocol, PPP Serial Data Transport Protocol
(PPP-SDTP), and an associated control protocol, PPP Serial Data
Control Protocol (PPP-SDCP). When these protocols are added to above
mentioned PPP protocols, PPP can be used to provide compression of
serial data on a point-to-point link.
This first edition of PPP-SDTP/SDCP covers HDLC-like synchronous
serial data and asynchronous serial data. It does this by using a
terminal adaption header based on that of ITU-T Recommendation V.120
[2]. Support may be added in the future for other synchronous
protocols as the marketplace demands.
The V.120 terminal adaption header allows transported data frames to
be split over several packets, supports the transport of DTE port
idle and error information, and optionally supports the transport of
DTE control state information.
In addition to the V.120 Header, fields can be added to the packet
format through negotiation to provide support for features not
included in the V.120 header. The extra fields are: a Length Field,
which is used to distinguish packets in compound frames, and a Port
field, which is used to provide multi-port multiplexing capability.
The protocol also allows reserved bits in the V.120 header to be used
to transport non-octet aligned frames and to provide a flow control
mechanism.
Schneider & Venters Informational [Page 2]
2024年6月13日发(作者：向景山)
Network Working Group K. Schneider
Request for Comments: 1963 S. Venters
Category: Informational ADTRAN, Inc.
August 1996
PPP Serial Data Transport Protocol (SDTP)
Status of This Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
Abstract
The Point-to-Point Protocol (PPP) [1] provides a standard method for
transporting multi-protocol datagrams over point-to-point links. PPP
defines an extensible Link Control Protocol, and proposes a family of
Network Control Protocols for establishing and configuring different
network-layer protocols.
This document describes a new Network level protocol (from the PPP
point of view), PPP Serial Data Transport Protocol, that provides
encapsulation and an associated control protocol for transporting
serial data streams over a PPP link. This protocol was developed for
the purpose of using PPP’s many features to provide a standard method
for synchronous data compression. The encapsulation uses a header
structure based on that of the ITU-T Recommendation V.120 [2].
Table of Contents
1. Introduction .......................................... 2
2. SDTP Packets .......................................... 3
2.1 Padding ......................................... 4
2.2 Packet Formats .................................. 4
3. Serial Data Control Protocol .......................... 11
4. SDCP Configuration Option Format ...................... 12
4.1 Packet-Format ................................... 13
4.2 Header-Type ..................................... 13
4.3 Length-Field-Present ............................ 14
4.4 Multi-Port ...................................... 14
4.5 Transport-Mode .................................. 15
4.6 Maximum-Frame-Size .............................. 16
4.7 Allow-Odd-Frames ................................ 16
4.8 FCS-Type ........................................ 17
4.9 Flow-Expiration-Time ............................ 18
SECURITY CONSIDERATIONS ...................................... 19
Schneider & Venters Informational [Page 1]
RFC 1963 PPP SDTP August 1996
REFERENCES ................................................... 19
CHAIR’S ADDRESS .............................................. 20
AUTHORS’ ADDRESSES ........................................... 20
1. Introduction
This document is a product of the TR30.1 ad hoc committee on
compression of synchronous data. It represents a component of a
proposal to use PPP to provide compression of synchronous data in
DSU/CSUs.
In addition to providing support for multi-protocol datagrams, the
Point-to-Point Protocol (PPP) [1] has defined an effective and robust
negotiating mechanism that can be used on point to point links. When
used in conjunction with the PPP Compression Control Protocol [3] and
one of the PPP Compression Protocols [4-10], PPP provides an
interoperable method of employing data compression on a point-to-
point link.
This document provides a PPP encapsulation for serial data,
specifying a transport protocol, PPP Serial Data Transport Protocol
(PPP-SDTP), and an associated control protocol, PPP Serial Data
Control Protocol (PPP-SDCP). When these protocols are added to above
mentioned PPP protocols, PPP can be used to provide compression of
serial data on a point-to-point link.
This first edition of PPP-SDTP/SDCP covers HDLC-like synchronous
serial data and asynchronous serial data. It does this by using a
terminal adaption header based on that of ITU-T Recommendation V.120
[2]. Support may be added in the future for other synchronous
protocols as the marketplace demands.
The V.120 terminal adaption header allows transported data frames to
be split over several packets, supports the transport of DTE port
idle and error information, and optionally supports the transport of
DTE control state information.
In addition to the V.120 Header, fields can be added to the packet
format through negotiation to provide support for features not
included in the V.120 header. The extra fields are: a Length Field,
which is used to distinguish packets in compound frames, and a Port
field, which is used to provide multi-port multiplexing capability.
The protocol also allows reserved bits in the V.120 header to be used
to transport non-octet aligned frames and to provide a flow control
mechanism.
Schneider & Venters Informational [Page 2]