.711 is a standard that outlines how to digitize an analog voice signal into digital. It is lossless, meaning that there is no degradation of call quality with its use. G. 711 is usually the best-sounding voice CODEC in common use, and it requires the least amount of DSP resources, because there is no compression. Unfortunately, great sound comes at a price, and G.711 consumes the most bandwidth (64 kbps per signal when sampled at 8 kHz). Since this is the same size as a traditional voice call, there is no economy of bandwidth, SO it is rarely used on a converged network. G.722 G.711 sounds good because it delivers the same sound quality as a traditional plain old telephone service (POTS) line. G.722 sounds even better because it delivers better sound quality than a POTS line. Commonly called wide-band audio because it samples at 16 kHz as opposed to 8 kHz for G.711, G.722 is supported on high- end phones like Cisco's 7575G. The downside of using this protocol is that it consumes more bandwidth than G.711. For this reason, it should be used only on local networks where bandwidth is plentiful. G.729 G.729 is a CODEC that compresses a voice signal with an average of 8:1 compres- sion. G.729 is very popular because it balances excellent voice quality with a sig- nificant reduction in network utilization. The downside is that G.729 requires more DSP resources. There are multiple versions of G.729-most notably, G.729a and G.729b. G.729a offers the same quality and compression, but uses an algorithm that requires fewer DSP resources. G.729b supports Voice Activity Detection Chapter 30: VolP (VAD), a feature that lowers or eliminates network utilization during periods of silence. Power over Ethernet (PoE) You may not think of PoE as a protocol, but it is. In the Cisco world, there are generally two protocols in common use: Cisco prestandard PoE and standards- based 802.3af. Cisco was selling PoE devices before there was a standard, hence the prestandard moniker. Many modern Cisco switches support both protocols, but be 