Benefits of VolP in Software

Encode Code 128 Code Set A in Software Benefits of VolP

Sending voice data over IP networks has some very attractive possible payoffs More Efficient Use of Available Connections Consider a large company with two main offices At any given time, hundreds of voice conversations may be occurring between those two offices Each traditional voice connection consumes one DS0 line, capable of

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carrying up to 56Kbps of data were the line to be used digitally Each conversation doesn t really use all of the available bandwidth on the line Part of this is because most conversations have a lot of silent spaces time between words or sentences, time where one party stops speaking and the other starts, and so forth Plus, most conversations, were they encoded digitally, could be significantly compressed Add all of this up together, and each voice conversation is likely to use only one-third to one-half of the available bandwidth on a single DS0 circuit If you were able to carry all of these voice conversations digitally, much less bandwidth would be required Instead of 100 DS0 lines for 100 conversations, for example, the same conversations might use up only 25 to 33 DS0 lines if they were digitally packaged Add up the cost savings, and you can see that many companies can save a significant amount of money by using VoIP VoIP Connections Are Packet-Oriented When the user places a call, a single connection is formed between the caller and the receiver This connection is static for the duration of the call If the conversation were digitized and sent over a packet-oriented network, however, many possible paths would be available for each packet, and much more redundancy would be automatically available For instance, if some portion of the network between the two points goes down, the packets could still arrive at their destination through an alternate route, just as data packets do over the Internet Also, available circuits would be used more efficiently, allowing more calls to be routed within a particular geographic area

There are also some problems with VoIP that you need to consider No Guaranteed Delivery VolP does not guarantee delivery of IP packets over the Internet For a digital transmission of data, this is no big deal; if a packet isn t confirmed as being received, it is simply retransmitted For a real-time voice conversation, on the other hand, the loss of packets directly inhibits the conversation, and you can t go back in time to retransmit missing packets Packets Arrive Out of Sequence Not only can IP packets simply fail to arrive at their destination on occasion, sometimes they arrive out of sequence due to other Internet traffic and other reasons This is fine for transmitting things like files, because they can be reassembled on the other end in the proper sequence For a real-time application such as voice, however, having packets arrive out of sequence results in a hopelessly jumbled, and thus useless, transmission QoS Not Widely Implemented Real-time uses of the Internet, such as VoIP or multimedia streaming, and time-sensitive transmissions should be given priority over transmissions that are not particularly time-sensitive, such as the transmission of an e-mail message Fortunately, IP has a Quality of Service (QoS) field that enables the user to prioritize traffic for such reasons However, QoS is not widely implemented in all parts of the Internet

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VoIP is a hot, emerging technology that is virtually certain to become an important part of the Internet and most companies networks However, as of early 2001 there is still much work to be done toward actually implementing this technology widely and solving more certainly the problems outlined in this section In other words, if you re learning about networking, you should be aware of VoIP what it is and what it does although most likely the technology will not become much of a factor in most networks for several years yet