14.3.2.1. Features 
IMPORTANT:
The availability of the following functionalities
depends on the SIP partner and must be tested individually!
- Basic Call in accordance with RFC3261 SIP (for supported RFCs please refer to Section 1.2, “Supported RFCs (Request for Comments) for SIP Interfaces”)
- CLIP/CLIR
- COLP/COLR
- Sending and receiving E.164 explicit international telephone numbers with a leading “+” (e.g. +498972237729) or implicit telephone numbers with prefixes (e.g. 00498972237729)
- Name display (e.g. for OpenScape Xpressions V6 connectivity)
- Call hold / retrieve / toggle
- Call transfer (attended call transfer / semi-attended call transfer / blind call transfer)
- Call forwarding ("forward switching" method)
- Diversion header
- Early media (183 Call Progress with SDP)
IMPORTANT:
Call forwarding via “Call rerouting method” is not
supported. Instead diversion header is supported (sending of call forwarding
information; required for call forwarding scenarios to SIP service provider).
- Conferencing (3 party conference)
- Message Waiting Indication MWI
-
This feature can be used for SIP connectivity towards service providers offering hosted Unified Messaging services.
- DNS SRV - Locating and addressing SIP servers/proxies using fully qualified domain names
- SIP proxy failover and recovery
- Registration to SIP service provider (registration to OpenScape 4000 from other vendors is not supported).
- Session border controller connectivity
- SIP session timer RFC4028 (more information can be found in Section 2.4, “Restrictions”)
- Digest authentication
- L2 and L3 QoS for signaling and payload
- T.38 fax connections (towards SIP service providers, e.g. T-Systems)
- DTMF signaling (Inband and RFC2833 compliant)
- Voice codecs G.729 and G.711
- Silence suppression
- Inband / outband proxy configuration
- SIP trunking profiles (enable easy SIP service provider integrations and administration)
- UDP/TCP transport
- IPv6 (see "OpenScape 4000 SoftGate" > Chapter 12, “IPv6”)
- Signaling (TLS) and payload encryption (SRTP) (see "Signaling and Payload Encryption (SPE)")
- Location-ID in the SIP-Header - GeoPriv PIDF-LO
INFO:
Emergency call behavior (including PANI and GeoPriv) corresponding in each SIP Profile to certified SIP partner requirements.OpenScape 4000 and OpenScapeVoice systems are normally networked via SIP-Q (see Section 3.1, “SIP-Q Trunking”).