IP Trunk - (SIP) Session

IP Trunk - (SIP) Session Initiation Protocol
Version 2.0 or higher software provides;
• When + is added to the country code of an incoming SIP trunk call, it is recognized as an
international call, simplifying outgoing calls from the incoming call list.
Description
The SL1100 IP Trunk SIP package sends the real time voice over the corporate LAN or WAN. The voice from the telephone is digitized and then put into frames to be sent over a network using Internet protocol.
Using VoIPDB equipment at a gateway (a network point that acts as an entrance to another network), the packetized voice transmissions from users in the company are received and routed to other parts of the company Intranet (local area or wide area network) or they can be sent over the Internet using CO lines to another gateway.
Depending on the requirements and resource allocation in the LAN/WAN/Internet, the VoIPDB - SIP can be configured to use any of the following voice compressions:
• G.711 μ-law - Highest Bandwidth
• G.729 (a) - Most often used
• The LAN/WAN or Internet connection is provided by a 10 Base-T/100 Base-TX Ethernet.
For a list of vendors that have successfully completed interoperability certification go to http:// www.necntac.com and refer to Technical Documentation.
SIP Trunk E.164 Support (V2.0 or higher)
With the SIP Trunk E.164 Support enabled the PBX is able to support SIP configurations where the number presentation within the SIP messages is formatted using the E.164 international numbering scheme. Specifically the system is able to handle the ‘+’ digit when required as the International Access Code.
For example a normal international SIP call could be dialed and presented from the system as follows; Number dialed = 00441202223344
Request-URI: Invite sip: 00441202223344@172.16.18.100 SIP/2.0
However with SIP Trunk E.164 Support enabled the SIP call could be presented once dialed as below; Request-URI: Invite sip:+441202223344@172.16.18.100 SIP/2.0
This presentation can be a requirement of certain SIP ITSPs (Internet Telephony Service Providers) so it is necessary the PBX can handle these calls and modify any SIP messages to the correct format accordingly.
Below is the full list of SIP header fields used by this feature: Request-URIToFromP-Asserted IdentityP-Preferred Identity
SIP Trunk E.164 CLIP Enhancement (V2.0 or higher)
With the SIP Trunk E.164 CLIP Enhancement enabled, when an incoming SIP call from an external ITSP is presented at the system with a “+” in the From header field as the international access code, it is recognized and displayed as an international call at the terminal display and also logged in the terminals incoming caller history, allowing any outbound calls made from a multiline terminals caller history possible using this numbering scheme.
This presentation can be a requirement of certain SIP ITSPs (Internet Telephony Service Providers) so it is necessary the PBX can handle these calls and modify any SIP messages to the correct format accordingly.