TekSIP

alternate endpoint when called endpoint is unavailable (Off-line, busy...). Active SIP session can be terminated via GUI. TekSIP has a Presence Server (SIP/SIMPLE based). TekSIP also supports UPnP IGD specification. If installed behind UPnP supported Internet gateway device (ADSL router e.g.), TekSIP automatically detects if it is behind a new NAT gateway and the external IP address. All outgoing requests manipulated for NAT traversal. You do not need to add manual reverse mappings for SIP and RTP protocols. TekSIP can optionally act as a B2BUA for incoming 3xx SIP responses. TekSIP can also act as a RTP Proxy and record audio streams if RTP proxy enabled. Recorded audio streams are saved in wave format can be played using TekSIP Manager. RADIUS Authentication (RFC 2865) and Accounting (RFC 2866) is supported. TekSIP monitors failed registration and call attempts from suspicious endpoints and blacklists them. You can monitor black listed endpoints through TekSIP Manager and you can remove black listed endpoints from quarantine list if required. You can also ban specific user agents. TekSIP also provides single accounts proxy; if you have just one provider account and many internal clients, TekSIP proxies all external calls for the provider account. TekSIP can register to upstream SIP servers to receive incoming calls.