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SIP Release Notes | 2. Supported Features |
2 Supported Features
This chapter describes various features supported by the device.
2.1SIP Gateway Features
This section lists the SIP Gateway application’s main features.
2.1.1Supported SIP Features
The device supports the following main SIP Gateway features:
Reliable User Datagram Protocol (UDP) transport, with retransmissions. Transmission Control Protocol (TCP) Transport layer.
SIPS using TLS.
T.38
Operates with proxy server, or without using an internal routing table. Fallback to internal routing table if proxy server does not respond.
Up to 32 IP Groups and 32 Proxy Sets. Each Proxy Set can comprise up to 15 IP addresses. If the primary proxy server fails, the device automatically switches to a redundant proxy server.
Up to 32 Registration Accounts, where each account can be used for operation with different ITSP/SIP Trunks.
Domain name resolving using DNS NAPTR and SRV records for Proxy, Registrar and domain names that appear in the SIP Contact and
Load balancing of proxy servers using round robin or random weights.
Proxy and registrar authentication (handling 401 and 407 responses) using MD5 Digest method. Accepted challenges are kept for future requests to reduce the network traffic.
Single device registration, multiple registration of all device endpoints, or registration per Trunk Group (using Accounts).
Supported SIP Methods (messages): INVITE, CANCEL, BYE, ACK, REGISTER, OPTIONS, INFO, REFER, UPDATE, NOTIFY, PRACK, SUBSCRIBE and PUBLISH.
Modifying connection parameters for an already established call
Early media (supporting 183 Session Progress). Receipt of SIP REFER messages outside of a dialog.
Responds to SIP OPTIONS messages outside a SIP dialog and in
Publishes the total number of free Tel channels in a 200 OK response to an OPTIONS requests.
Receipt and DNS resolution of FQDNs received in SDP. Negotiation of coder from a list of given coders. Negotiation of dynamic payload types.
Multiple ptime values per coder.
Version 6.2 | 115 | December 2010 |