SCTP Programmer's Guide

NOTE: In SCTP, the term “stream” refers to a sequence of user messages that are
delivered in sequence, with respect to other messages within the same stream. In TCP,
“stream” refers to a sequence of bytes.
HP's implementation of SCTP conforms to the following RFCs and draft RFCs:
• RFC 3286 (An Introduction to the Stream Control Transmission Protocol (SCTP))
• RFC 2960 (Stream Control Transmission Protocol)
• RFC 3873 (Stream Control Transmission Protocol (SCTP) Management Information Base
(MIB))
• RFC 4460 (Stream Control Transmission Protocol (SCTP) Specification Errata and Issues)
• RFC 3309 (Stream Control Transmission Protocol (SCTP) Checksum Change)
• RFC 3758 (Stream Control Transmission Protocol (SCTP) Partial Reliability Extension)
• draft-ladha-sctp-nonce-01.txt (ECN Nonces for Stream Control Transmission Protocol
(SCTP))
• draft-ietf-tsvwg-addip-sctp-10.txt (Stream Control Transmission Protocol (SCTP)
Dynamic Address Reconfiguration)
• draft-stewart-sctp-pktdrprep-02.txt (Stream Control Transmission Protocol (SCTP)
Packet Drop Reporting)
•
Limitations of TCP and UDP
TCP and UDP are the most widely used network layer protocols. However, the data
transfer services offered by these protocols are inadequate to meet the requirements
of a wide range of commercial applications, such as real-time multimedia and
telecommunication applications. These applications require a robust protocol, which
provides the flexibility of UDP and reliability of TCP, for transferring data between
two endpoints.
This section discusses the limitations of the TCP and UDP protocols, which led to the
development of SCTP.
This section addresses the following topics:
• “Limitations of TCP” (page 18)
• “Limitations of UDP” (page 19)
Limitations of TCP
Following are the limitations of TCP:
• TCP provides reliable data transfer, but it transmits data in a sequence. However,
some applications may need reliable data transfer, though not necessarily in a
strict sequence. These applications prefer partial ordering of data, wherein ordering
is maintained only within subflows of data. The strict sequence maintenance in
18 Introduction