As is often the case some interesting stuff on the weekly VUC call was recorded in the session after the formal call ends. This weeks post call discussion about conferencing, Talkshoe, the cancellation of Skypecasts and HDVoice was really interesting. Thankfully Randy, our esteemed host, records the post-call chatter and uploads it when it’s useful. You can download it here.
Karl Fife, a VUC regular and fellow wideband voice advocate, corrected his assertion made a few months back about Polycom working some magic to enhance basic G.711 calling on the IP550 and IP650 phones. As he tells it, he had at one time made a call dialing out through an ITSP to a PSTN number, where the call was received via another ITSP and passed to a Cisco IP phone. The Polycom phone display had indicated “HD” and the call quality was excellent. This gave rise to the suspicion that Polycom had implemented some form of enhancement to the basic G.711 encoding used on the PSTN.
Polycom IP550 indicating HD, which means a G.722 encoded call
While at Astricon 08 he spoke to people from Polycom and found that what he thought he had experienced, while an excellent quality call, was likely not “enhanced” G.711 as he suspected. It was just a best case call between a pair of excellent end-points over well run networks. The fact that the Polycom phone indicated “HD” (as shown above) might be explained as simply a bug in the phones firmware.
I am especially happy to get this clarification as I had been pondering what might be going on under the covers for quite some time. Karl is a knowledgeable guy and one of the reasons why I’m drawn to the weekly VUC. It’s always an interesting group of VoIP geeks doing what they do best…Geek Speak!
The pity is that I had to discover this weeks call after the fact as I was flying home from Seattle at the time it occurred. Earning a living is such a bother sometimes.