Voice-only with different codecs
From TD-er's Wiki
Experimental Setup
In order to gain inside in the bandwitdh usage when SIP-phones use different codecs, the following experimental setup is used. A voice-call has been established between SIP-phone 201, which uses the GSM-codec and SIP-phone 301, which uses the G711u-codec.
Results
With WireShark data has been collected and the following filters are used in the in I/O-graph:
Filter-Black: proto=sip Filter-Red : ip.addr == 192.168.1.3 && ip.addr == 192.168.1.106 Filter-Green: ip.addr == 192.168.1.189 && ip.addr == 192.168.1.101 Filter-Blue : ip.addr == 192.168.1.106 && ip.addr == 192.168.1.101 Filter-Pink : ip.addr == 192.168.1.100 && ip.addr == 192.168.1.101
This does not tell us which Asterisk box makes the conversion between the GSM codec and the G711u codec. Therefore we made another graph with the traffic measured only in one direction.
Used filters in I/O-graph:
Filter-Black: ip.src == 192.168.1.101 && ip.dst == 192.168.1.106 Filter-Red : ip.src == 192.168.1.3 && ip.dst == 192.168.1.106 Filter-Green: ip.src == 192.168.1.189 && ip.dst == 192.168.1.101 Filter-Blue : ip.src == 192.168.1.106 && ip.dst == 192.168.1.101 Filter-Pink : ip.src == 192.168.1.100 && ip.dst == 192.168.1.101
Conclusions
- Tsah
