User Agent Client (UAC)
Definition - What does User Agent Client (UAC) mean?
A User Agent Client (UAC) is a Session Initiation Protocol (SIP) or Voice over Internet Protocol (VoIP) application that serves as a peer-to-peer (P2P) communication gateway and generates distributed network service requests.
A UAC is a network server, email client, search engine or Web browser.
Techopedia explains User Agent Client (UAC)
Request for Comments (RFC) 1945 requires:
- All UAC formats must include a product and optional comment string.
- The user agent (UA) header field is used by HTTP, SIP and Simple Mail Transfer Protocol/Network News Transfer Protocol (SMTP/NNTP).
The UAC submits its ID string to the User Agent Server (UAS) with application type, OS or client/server revisions.
In a Web browser, the UA string format reads as follows:
Mozilla/[version] ([system and browser information]) [platform] ([platform details]) [extensions]
- Session Initiation Protocol (SIP)
- User Agent Server (UAS)
- User Agent (UA)
- Hypertext Transfer Protocol (HTTP)
- Simple Mail Transfer Protocol (SMTP)
- Voice Over Internet Protocol (VoIP)
- SIP for Instant Messaging and and Presence Leveraging Extensions (SIMPLE)
- Session Initiation Protocol Trunking (SIP Trunking)
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