The Transmission of IP Datagrams over the SMDS Service
RFC 1209
Document | Type |
RFC - Internet Standard
(March 1991; No errata)
Also known as STD 52
|
|
---|---|---|---|
Authors | Joe Lawrence , David Piscitello | ||
Last updated | 2013-03-02 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 1209 (Internet Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | (None) | ||
Send notices to | (None) |
Network Working Group D. Piscitello Request for Comments: 1209 J. Lawrence Bell Communications Research March 1991 The Transmission of IP Datagrams over the SMDS Service Status of this Memo This memo defines a protocol for the transmission of IP and ARP packets over a Switched Multi-megabit Data Service Network configured as a logical IP subnetwork. This RFC specifies an IAB standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "IAB Official Protocol Standards" for the standardization state and status of this protocol. Distribution of this memo is unlimited. Abstract This memo describes an initial use of IP and ARP in an SMDS service environment configured as a logical IP subnetwork, LIS (described below). The encapsulation method used is described, as well as various service-specific issues. This memo does not preclude subsequent treatment of the SMDS Service in configurations other than LIS; specifically, public or inter-company, inter-enterprise configurations may be treated differently and will be described in future documents. This document considers only directly connected IP end-stations or routers; issues raised by MAC level bridging are beyond the scope of this paper. Acknowledgment This memo draws heavily in both concept and text from [4], written by Jon Postel and Joyce K. Reynolds of ISI and [5], written by David Katz of Merit, Inc. The authors would also like to acknowledge the contributions of the IP Over SMDS Service working group of the Internet Engineering Task Force. Conventions The following language conventions are used in the items of specification in this document: o MUST, SHALL, or MANDATORY -- the item is an absolute requirement of the specification. IP over SMDS Working Group [Page 1] RFC 1209 IP and ARP over the SMDS Service March 1991 o SHOULD or RECOMMENDED -- the item should generally be followed for all but exceptional circumstances. o MAY or OPTIONAL -- the item is truly optional and may be followed or ignored according to the needs of the implementor. Introduction The goal of this specification is to allow compatible and interoperable implementations for transmitting IP datagrams and ARP requests and replies. The characteristics of the SMDS Service and the SMDS Interface Protocol (SIP) are presented in [3], [6], and in [7]. Briefly, the SMDS Service is a connectionless, public, packet-switched data service. The operation and features of the SMDS Service are similar to those found in high-speed data networks such as LANs: o The SMDS Service provides a datagram packet transfer, where each data unit is handled and switched separately without the prior establishment of a network connection. o The SMDS Service exhibits high throughput and low delay, and provides the transparent transport and delivery of up to 9188 octets of user information in a single transmission. o No explicit flow control mechanisms are provided; instead, the rate of information transfer on the access paths is controlled both in the subscriber-to-network direction and in the network- to-subscriber direction through the use of an access class enforcement mechanism. o Both individually and group-addressed (multicast) packets can be transferred. o In addition to these LAN-like features, a set of addressing- related service features (source address validation, source and destination address screening) are provided to enable a subscriber or set of subscribers to create a logical private network, or closed user group, over the SMDS Service. The access control provided by the closed user group mechanism is supplied by the SMDS provider according to the specifications stated in [3]. o SMDS addresses are 60 bits plus a 4 bit Address Type. The Address Type subfield occupies the 4 most significant bits of the destination and source address fields of the SIP Level 3 Protocol Data Unit (PDU). It contains the value 1100 to IP over SMDS Working Group [Page 2] RFC 1209 IP and ARP over the SMDS Service March 1991 indicate an individual address and the value 1110 for a 60-bit group address. The SMDS Interface Protocol is based on the IEEE Standard 802.6, Distributed Queue Dual Bus (DQDB) Connectionless MAC protocol [8]. The SMDS service layer corresponds to the IEEE 802 MAC sublayer. TheShow full document text