Collisions, broadcast or bandwidth may cause serious problems due to modification in clients conditions. To solve these obstacles people who deal with designing computer networks need to think and take into consideartion new users requirements and multiple applications what contributed that traffic patterns became more important instead of alone classic issues.

There were no longer possibility to create sub-nets by adding diffrent sections into each sub-net. Designers need to reflect on giving all users equal access to various and numerous network services in an easy and convenient way.

Typical structure where the main server was located in one room became slow, out of date and in many cases did not meet the customer needs. We need to find a soultion of these problem connected with bandwidth issues what could be achieved using special techiques concerning sophisticated routers and switches. That is why the designers started to think and create a new campus model.

Complex applications like audio and video, VOIP, etc. that could be transmitted in internet network required new campus model. This model must assure:

- quick adaptation to the new changable conditions,

- definite paths which enable clients to achieve access to the network without any problems,

- design that make possible the proper functiong when the links fail,

- adaptation to the new devices and applications,

- applications which support all clients and users in the network,

- assistance in the multiple protocols, especially regarding routing,

- multi-transmission to a specific group of people or sub-nets.