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Traditional Telecommunications Network
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| bet | 4/32 | | Sana | 22.07.2021 | | Hajmi | 0,89 Mb. | | #15652 |
2.1 Traditional Telecommunications Network
This sub section looks at the traditional telecommunication network, to observe the current systems that future users of the VoIPv6 application are using with the aim, to establishing a list functionality which should be provided within the VoIPv6 application.
The traditional telecommunications network has been around for over 100 years, it allows terminals namely telephone to be plugged in to the network and for a telephone number to be dialled and a connection from one telephone to the other is established.
The Telecommunications Network works by creating a connection between the two machines over the network for the duration of the call. Voice data is sent in both analogue and in digital forms from end point to end point. Over the main part of the network voice data is sent in a digital format, since a digital format is easier to manipulate such as multiplexing and digital network are a lot more efficient than their analogue counterparts. Data is sent in an analogue format at the local loop or what is known as the last mile, namely between the telephone and the exchange.
The benefits of using simple cheap telephone terminals which simply send analogue signals to the exchange where all the real work is done, is that any upgrade in the network can be done transparently to the users, which both cuts down on costs and does not require contacting the user.
The telecommunications network are also highly reliable and available, for an operator to have a telecommunications licence they have to maintain a high availability of a HAL of 5, which is a availability level of 99.999% of the time, in real terms the network can only be down for 5 minutes per year. In reality network operator’s aim for a HAL of 6, which means the network is available 99.9999% of the time.
Telecommunication networks are very costly to run and the costs passed on to the customers though telephone charges. So it seems impractical to have two networks running layered upon each other where one would be adequate. This is one of the main driving forces behind such applications as VoIP, to provided voice over these data networks such as the internet, so when then convergence of networks occurs there are applications available to replace the functionality lost of the telecommunication networks.
The network provides a number of different functions to the user, the standard telephone functions are provided such as the capability to make a call, hang up a call, accept a call and reject a call. These functions have been around for over a hundred years, however today these are not the only functions provided by the network, today with every operator expected to provide a highly reliable available network they have to provide additional value added services.
There are a number of value added services being offered by different operators the mobile phone operates have the service of being mobile which was once an added service but know expected. Other value added service are available such as answer phone, where message from missed callers are received, Conferencing where a number of different calls can all take part in phone call, Caller-ID where the ringing callers number is displayed to aid in the decision on whether to answer.
All these services are provided by the telecommunications company and in real terms would be expected of any VoIP applications which were proposed to replace the telephone.
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