Cisco SPA2102-SF Administration Guide - Page 165

ATA Voice Field Reference Line page B Voice tab > Line page > SIP Settings section Field SIP Transport Description The TCP choice provides "guaranteed delivery," which assures that lost packets are retransmitted. TCP also guarantees that the SIP packages are received in the same order that they were sent. As a result, TCP overcomes the main disadvantages of UDP. In addition, for security reasons, most corporate firewalls block UDP ports. With TCP, new ports do not need to be opened or packets dropped, because TCP is already in use for basic activities such as Internet browsing or e-commerce. Options are: UDP, TCP, TLS. The default is UDP. SIP Port Applies to SPA2102, SPA3102, and SPA8800. Port number of the SIP message listening and transmission port. The default is 5060. SIP 100REL Enable To enable the support of 100REL SIP extension for reliable transmission of provisional responses (18x) and use of PRACK requests, select yes. Otherwise, select no. EXT SIP Port Auth ResyncReboot The default is no. The external SIP port number. If this feature is enabled, the ATA device authenticates the sender when it receives the NOTIFY resync reboot (RFC 2617) message. To use this feature, select yes. Otherwise, select no. SIP Proxy-Require SIP Remote-PartyID The default is yes. The SIP proxy can support a specific extension or behavior when it sees this header from the user agent. If this field is configured and the proxy does not support it, it responds with the message, unsupported. Enter the appropriate header in the field provided. To use the Remote-Party-ID header instead of the From header, select yes. Otherwise, select no. The default is yes. Cisco Small Business ATA Administration Guide 165