The Fusion SDP Toolkit provides functions to parse Session Description Protocol (SDP) announcements into convenient C structures and to build SDP announcements using the same C structures as inputs. The parser is specifically targeted at parsing SDP announcements for the RTP/AVP transport with media formats using the numerical payload types. The parser is ideally suited for use in mainstream applications such as VoIP.
SDP is a text-based protocol used to describe multi-media sessions. It is a general-purpose protocol designed for use in a range of applications from Voice over IP (VoIP) to ad-hoc multicast conferences. A description of a multi-media session is termed an “announcement” or SDP announcement.
Fusion SDP RFC Compliance and Features
- RFC 2327 (SDP: Session Description Protocol)
- RFC 3264 (An Offer/Answer Model with the Session Description)
Protocol (SDP)
- RFC 3551 (RTP Profile for Audio and Video Conferences with Minimal Control)
Per RFC 2327 Parses and builds all fields, including complex multicast
connection fields, complex time fields with repeat times and zone adjustments,
etc.
- Unlike text-only SDP parsers, the parser converts strings representing numbers
such as RTP port numbers, bandwidths, etc. into numerical values. Likewise, the
builder converts numerical values into strings.
- The toolkit groups together logically associated fields into a single C structure.
For example, the “rtpmap” and “fmtp” attributes found in media-descriptions are
grouped together with the corresponding format from the media-field format list
providing logical coherence for these fields.
- Provides both high-level API calls that can parse/build and entire SDP
announcement, and provides low-level functions for parsing/building individual
fields of SDP announcements
- 100% ANSI C using porting macros for all system dependencies (C runtime
functions etc.) for the ultimate in portability
- Simple architecture makes it easy to enhance as required to support new extensions to SDP as they arise
|
