VoIP (Voice Over IP) Codecs

Voice over Internet Protocol or VoIP is a revolutionarysecond. It depends on the codec which is being used
technology which takes analog audio signals and turnsthat's what are the sampling rates like 64,000 times
them into digital data which can be transmitted overper second, 32,000 times per second or 8000 times
the internet. It has the potential to wholly revolutionizeper second. Out of this most commonly used codec is
the world's phone system. Its providers are alreadyG.729A codec which has sampling rate of 8000 times
very successful and major carriers, such as Vonage,per second.
AT&T are in the process of setting up VoIP plansA Codec uses advanced algorithm for the purpose of
across United States. Above all, VoIP is basically verysorting, sampling, and compressing and finally packetize
clever invention which has the future capability tothe data. The most prevalent algorithm is CS-ACELP
replace the so called traditional phones or even cellalgorithm in VoIP. It stands for conjugate-structure
phones because of quality and cost.algebraic-code-excited linear prediction. It functions by
Now we talk about VoIP codecs: Codec whichorganizing and streamlining the bandwidth availability.
basically stands for Corder-Decorder functions byAnother aspect of this is Annex-B which functions by
converting audio signals into compressed digital signalscreating the rule of transmission as it states that if no
for the purpose of transmission and again intoone is talking then don't send the data. This rule
uncompressed signals to replay. This is the essence ofcreated so much efficiency in its greatest ways that
Voice over Internet Protocol. Codecs sample the audiopacket switching became superior to circuit switching.
signals thousands times per seconds and therebyThe codec works by using the algorithm for converting
accomplish the very purpose of conversion. Example-and sorting everything out. But it fails when you don't
G.711codec which samples the audio at a speed ofknow where to send the data. This problem is handled
64000 times a second. Each tiny sample is convertedthrough the use of soft switches. These switches use
into digital data and then compressed for transmission.a numbering system so as to route the phone call
Now after reassembling 64000 samples, pieces oftowards the area codes. Based on this numbering
missing audio become very small to the human ear,system anyone can be located conveniently, no
that when you listen seems like one continuousmatter in which corner of the world.