IMG 1010 - Overview of H.323
The IMG supports Version 2 of ITU H.323, including:
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H.225 Call Signaling Protocol (Q.931 embedded)
Registration, Admission, and Status (RAS)
Real-time Transport Protocol/Real-time Transport Control Protocol (RTP/RTCP)
Out-of-band DTMF signaling via H.245 and RFC2833
Cisco Interoperability
Media:
DTMF transmission supported via DTMF tones using G.711, or out via RFC 2833 or H.245 UII signals.
T.38 Fax, Fax Bypass, Modem Bypass (seeĀ IMG 1010 - H.323 Fax-Modem Techniques)
Codecs: G.711 (Uncompressed), G.723.1 (Compressed), G.729 (Compressed), G.726 (Dynamic and Static), iBLC
Codec Negotiation Both incoming and outgoing calls including the ability to limit the codecs that are allowed
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Cause code mapping to SS7 ISUP
Cause code mapping of H.225 release reasons to Q.931 cause codes using H.246 interworking specification
H.245 Tunneling - H.245 data is sent with the H.225 message
ISDN to H.323 UUI support
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Simultaneous gateway and gatekeeper routed calls
Gatekeeper Support: 1 active gatekeeper and six alternate, auto-discovery, aliases for E.164, URL, and email.