GNU SIP Witch is a pure SIP-based office telephonecall server that supports generic phone systemfeatures like call forwarding, hunt groups andcall distribution, call coverage and ring groups,holding, and call transfer, as well as offeringSIP specific capabilities such as presence andmessaging. It supports secure telephone extensionsfor making calls over the Internet, andintercept/decrypt-free peer-to-peer audio andvideo extensions. It is not a SIP proxy, amulti-protocol telephone server, or an IP-PBX, anddoes not try to emulate Asterisk, FreeSWITCH, or Yate.License: GNU General Public License v3Changes:
This initial release supports SIP registration, multi-target registration, authentication peering over SIP, registration querying of user agents, basic call processing between registered user agents including call distribution for multi-target registrations, and basic SIP instant messaging.

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