Aastra OpenCom 510 User Guide - Page 127
SIP Provider, PBX Networking, Configuration
View all Aastra OpenCom 510 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 127 highlights
Voice over IP (VoIP) SIP Telephony ■ You must log on ("Login") to the SIP registrar before you can use SIP telephony. Use the OpenCom 510 to manage important information for the registration (user name and password) of one or more SIP accounts. It is possible to make several calls simultaneously using a single SIP account. ■ A SIP connection causes constant Internet data traffic, so do not use SIP with Internet access which is paid for according to the time used. ■ RTP call data is also exchanged directly between terminals for SIP telephony, so different codecs can be used for sending and for receiving. It is also possible to change codecs dynamically during a call. You should use every codec available in the VoIP profile at least once, because this will enable you to establish connections with as many SIP subscribers as possible. ■ Fairly large packet lengths are quite normal on the Internet. They compensate for the longer packet propagation delay. ■ A bidirectional RTP data stream with a dynamically-assigned UDP port number is used to set up calls between subscribers. For this reason, incomng RTP calls often fail to get past the Firewall or NAT configuration of the Internet gateway product used. Do not use OpenCom 510 as an Internet gateway if the product used is to be compatible with SIP telephony. These products provide a "Full Cone NAT" setting for this application. ■ To enable the use of multiple devices on a single Internet connection, the IP addresses used in a LAN (often 192.168.x.x) are translated to a valid IP address using address translation (NAT - Network Address Translation), but no status information is available for NAT on an incoming RTP connection.To avoid this problem, the IP address of a workplace computer or telephone visible on the Internet is determined using a STUN server (STUN: Simple Traversal of UDP over NAT). You can ask your SIP provider for the STUN server.'s IP address and port number If you don't need a STUN server, leave the SIP Provider field empty. ■ For direct SIP telephony using OpenCom 510, only SIP IDs consisting of numbers for identifying subscribers registered with the SIP provider specified can be addressed ■ For each SIP account you can create just one bundle. You can specify this bundle in routes as a connection option. You can use a network provider rule to specify the routing of numbers within a specific range to use SIP telephony as a preference (see also PBX Networking, under Configuration starting on page 157). 125