Operation Manual
Vigor1000 Series User’s Guide 
208
notice sound will appear to tell the user new phone call is 
waiting for your response. Click hook flash to pick up the 
waiting phone call. 
Call Transfer- Check this box to invoke this function. 
Click hook flash to initiate another phone call. When the 
phone call connection succeeds, hang up the phone. The 
other two sides can communicate, then. 
Codecs 
Prefer Codec- Select one of five codecs as the default for 
your VoIP calls. The codec used for each call will be 
negotiated with the peer party before each session, and so 
may not be your default choice. The default codec is 
G.729A/B; it occupies little bandwidth while maintaining 
good voice quality. 
If your upstream speed is only 64Kbps, do not use G.711 
codec. It is better for you to have at least 256Kbps 
upstream if you would like to use G.711. 
Single Codec – If the box is checked, only the selected 
Codec will be applied. 
Packet Size- The amount of data contained in a single 
packet. The default value is 20 ms, which means the data 
packet will contain 20 ms voice information. 
Voice Active Detection- This function can detect if the 
voice on both sides is active or not. If not, the router will 
do something to save the bandwidth for other using. Click 
On to invoke this function; click off to close the function. 
Default SIP Account 
You can set SIP accounts (up to six groups) on SIP 
Account page. Use the drop down list to choose one of the 
profile names for the accounts as the default one for this 
phone setting. 
Play dial tone only when account registered - Check this 
box to invoke the function. 










