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:
External routing of SIP invites when dialingexternal SIP URIs is supported. Injecting SMSmessages to local stations through the sipwitchcontrol interface is supported. SIP requests foranonymous and system calling identifers can behandled.

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