Genre: eLearning | HF: 820 MB

INE’s CCIE Voice Advanced Technologies Class is the first step in understanding CCIE level technologies and is a companion to the Advanced Technologies Lab Workbook. Each technology you need to know for the CCIE Voice lab will be described in detail using an instructor led hands on demonstration. The Class-on-Demand is accessible in recorded format through your online member’s account 24 hours a day, 7 days a week! Candidates with reliable/always-on internet connections, who study mostly from their computers, will benefit most from this edition. With the online format, you can log in to your account from any computer connected to the internet, and all you need is a modern browser and Adobe Flash Player installed. You can watch and re-watch the recordings as much as you like, and download all the slide PDF’s from the class to assist in your studies.


Nowadays we take it for granted that someone in England can make a phone call to Australia, or that someone in India can read web pages that are on a computer in Canada. We live in a society in which almost every home has its own telephone line which is connected to a local exchange in the nearest village or town, from there to a main exchange in the nearest city, and from there to any other city in any country in the world. In this way, a person is able to dial a friend in another country just as easily as if they were in the same street.
BT’s Worldwide Network Management Centre

Inside BT’s Worldwide Network Management Centre at Oswestry.
(© British Telecommunications plc)

In order that these large and complicated networks can work properly, mathematics and computer simulation have to be used to understand the networks. The aim is to find out how large networks can be designed and controlled to provide reliable communications systems and to use resources efficiently. The reliable and efficient operation of networks is of vital commercial importance to both users and telephone companies, and even modest percentage improvements can correspond to large revenue gains.
BT’s Worldwide Network Management Centre

BT cable laying in the City of London.
(© British Telecommunications plc)

A large network is affected by many factors which are often hard to predict. There can be busy and quiet periods through the day. If a television program has a phone-in vote, there can be a sudden overload at one point in the network. If a digger cuts through a major telephone wire while repairing the road, there can be a sudden and unexpected failure. Mathematicians have developed ingenious ways of routing calls which can cope with these unpredictable events. These routing schemes work by searching out the spare capacity in the network so as to route calls away from parts of the network that are broken or full and into parts that are underloaded.

A good routing strategy doesn’t only need to be able to find the spare capacity in the network. In order to work well in real networks, it needs to be simple, so that thousands of calls a second can be routed instantly. It also needs to be decentralised; a central controller would be much too slow and could go disastrously wrong if it had a power failure, or got cut off from the rest of the network. Mathematicians have recently been able to show the surprising fact that these different goals can all be achieved simultaneously. Even simple, decentralised schemes can find the spare capacity as efficiently as more complicated schemes.



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