VoIP Industry News & Updates.- There are three issues with VOIP, in ascending order of annoyance:
- audio quality
- latency
- dropouts
For example:
I noticed a definite improvement in Skype quality when the broadband service is upgraded to DSL to 1.5M/896K from 640K/256K. Supposedly, even a dialup is usable, and any broadband should be OK. I suspect that it isn't just a matter of bandwidth to accomodate the Skype packets, but also what else may be flowing on the pipe, and that the more margin you have the better.
The other thing that I noticed is that a headset on a desktop Mac, connected directly to the network which has the DSL modem (I have a static /29, so there's no NAT on my DSL service), performs noticably better than a wireless phone going to a Windows laptop (with a faster CPU than the Mac!) which goes by 802.11/g to a Linksys WAP/NAT/router and then on to the network which has the DSL modem.
In *theory*, the DSL line should be the bottleneck in either case, because everything else is faster than the DSL's maximum bandwidth. In *practice*, the more hops things take, the less well it will work.
Another factor is that a laptop is frantically trying to conserve power while it's sitting idle. Laptops really not a good platform to run a lot of network I/O without someone interacting at it. If it's in its screen saver, don't expect it to be high-bandwidth I/O.
Unfortunately, the cordless phone doesn't have a Mac driver yet, so it can't try it on the Mac desktop and see how much the cordless aspect of the phone cuts into performance. I hope that will change soon.
What this all means is that you have to do some engineering and empirical testing before you get something that you will find satisfactory. The first thing that you try probably will not be what you want to use. What looks good on paper may not be the best solution.
There is also the general engineering rule: simpler is better.
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