User Agent Client

What Does User Agent Client 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.

Techopedia Explains User Agent Client

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]

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Margaret Rouse

Technology expert

Margaret is an award-winning writer and educator known for her ability to explain complex technical topics to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles in the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret’s idea of a fun day is to help IT and business professionals to learn to speak each other’s highly specialized languages.

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