Terms used throughout the NocTel universe.
Codec
"Codec" is a technical name for "compression/decompression". It also stands for "compressor/decompressor" and "code/decode". All of these variations mean the same thing: a codec is a computer program that both shrinks large data, and makes it smaller to transport across the Internet. To help speed up transport of audio, mathematical "codecs" were built to encode ("shrink") a signal for transmission and then decode it for listening. Without codecs, downloads would take longer or consume more bandwidth than the original version. With today's high bandwidth connections, codecs are not as important as they once were not so many years ago.
Codec Quality
A non-compressed codec, G711, will give the best voice quality, as no compression and decompression is required. This in turn makes this G711 less susceptible to packet loss, which even in small amounts will quickly degrade voice quality. Other codecs which use compression techniques consume less bandwidth, a good thing, but this compression process in itself lowers the voice clarity and introduces a delay. Additionally, compressed codecs are even more susceptible to packet loss. In addition G711 will maintain better quality with more latent connections, whereas compressed codecs' voice quality can quickly degrade as latency increase, as the chart below reflects.
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