Cisco SPA1001 Administration Guide - Page 80

Call Scenarios • Symmetric RTP, page 4-8 • Call Progress Tones, page 4-8 Chapter 4 Configuring the PSTN Gateway (FXO) PSTN Call to Ring Line 1 This feature allows a PSTN caller to ring Line 1. When the PSTN line rings, the PSTN Line makes a local VoIP call to Line 1. If Line 1 is busy, it stops. After a given number of rings, the VoIP gateway picks up the call. Symmetric RTP Symmetric RTP is used to send audio RTP to the source IP and port of the inbound RTP packets. This facilitates NAT traversal. Table 1-33 lists symmetric RTP parameters. Table 1-33 Symmetric RTP Parameters Parameter Symmetric RTP Symmetric RTP Group Line 1 PSTN Line Description Range Enable symmetric RTP operation. If enabled, SPA3102 sends RTP packets to the source address of the last received valid inbound RTP packet. If disabled, SPA3102 sends RTP to the destination as indicated in the inbound SDP. Default is yes. Yes or No Same as above. Default is yes. Yes or No Call Progress Tones Table 1-34 Call Progress Tones Call Progress Tone VoIP PIN Tone PSTN PIN Tone Outside Dial Tone Description This tone is played to prompt a VoIP caller to enter a PIN number. This tone is played to prompt a PSTN caller to enter a PIN number. During two-stage PSTN-gateway dialing and with a dial plan assigned, the SPA3102 collects digits from the VoIP caller and processes the number using the dial plan. The SPA3102 plays the to prompt the VoIP caller to enter the PSTN number. This tone should be specified to sound different from the PSTN dial tone. Call Scenarios This section describes some typical scenarios where the SPA3102 can be applied. Some terms are introduced in the first few sections and reused in later sections. This section includes the following topics: Linksys ATA Administrator Guide 4-8 Document Version 3.1