CIP Transport Protocols (RFC2653)
Original Publication Date: 1999-Aug-01
Included in the Prior Art Database: 2019-Feb-10
Internet Society Requests For Comment (RFCs)
J. Allen: AUTHOR [+2]
This document specifies three protocols for transporting CIP requests, responses and index objects, utilizing TCP, mail, and HTTP. [STANDARDS-TRACK]
Network Working Group J. Allen Request for Comments: 2653 WebTV Networks, Inc. Category: Standards Track P. Leach Microsoft R. Hedberg Catalogix August 1999
CIP Transport Protocols
Status of this Memo
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (1999). All Rights Reserved.
This document specifies three protocols for transporting CIP requests, responses and index objects, utilizing TCP, mail, and HTTP. The objects themselves are defined in [CIP-MIME] and the overall CIP architecture is defined in [CIP-ARCH].
In this section, the actual protocol for transmitting CIP index objects and maintaining the mesh is presented. While companion documents ([CIP-ARCH] and [CIP-MIME]) describe the concepts involved and the formats of the CIP MIME objects, this document is the authoritative definition of the message formats and transfer mechanisms of CIP used over TCP, HTTP and mail.
The philosophy of the CIP protocol design is one of building-block design. Instead of relying on bulky protocol definition tools, or ad-hoc text encodings, CIP draws on existing, well understood Internet technologies like MIME, RFC-822, Whois++, FTP, and SMTP. Hopefully this will serve to ease implementation and consensus
Allen, et al. Standards Track [Page 1]
RFC 2653 CIP Transport Protocols August 1999
building. It should also stand as an example of a simple way to leverage existing Internet technologies to easily implement new application-level services.
The key words "MUST" and "MAY" in this document are to be interpreted as described in "Key words for use in RFCs to Indicate Requirement Levels" [KEYWORDS].
Formal syntax is defined using ABNF [ABNF].
In examples octets sent by the sender-CIP are preceded by ">>> " and those sent by the receiver-CIP by "<<< ".
2 MIME message exchange mechanisms
CIP relies on interchange of standard MIME messages for all requests and replies. These messages are passed over a bidirectional, reliable transport system. This document defines transport over reliable network streams (via TCP), via HTTP, and via the Internet mail infrastructure.
The CIP server which initiates the connection (conventionally referred to as a client) will be referred to below as the sender-CIP. The CIP server which accepts a sender-CIP’s incoming connection and responds to the sender-CIP’s requests is called a receiver-CIP.
2.1 The Stream Transport
CIP messages are transmitted over bi-directional TCP connections via a simple text protocol. The transaction can take place over any TCP port, as specified by the mesh configuration. There is no "well known port" for CIP transactions. All...