A Voip Telephony System Design For Multinationals Based On Cisco Platform

The technology of transmitting voice over Internet Protocol is called VoIP. Because of VoIP’s numerous technical advantages, now it has already become an upcoming technology in this communication era and meanwhile it’s believed to still have a very huge service potential in the future.From a corporate’s standpoint, one big advantage brought by VoIP is the cost saving on communication with operation after implementation because it can transmit point to point communication over an existing WAN instead of through a carrier so that the long distance toll can be saved. Meanwhile, another aspect which makes VoIP attractive is its technical superiority of carrying data, voice & video over Internet Protocol on a converged network-a single network infrastructure using existing network equipment.Nowadays, more and more enterprises, especially those large multinationals are enthusiastic about deploying a VoIP Telephony system to get a converged network & telephony solution within the organization because an enterprise application converged with data, voice, video & collaboration no doubt produces more value-added effects comparing to those traditional disperse, standalone & self-running application thus it could better support the business requirement of enterprises nowadays.In this thesis, the author is researching and designing a VoIP Telephony system to meet the need of similar enterprises based on the VoIP deployment project in China & Northeast Asia region of the multinational manufacturing enterprise the author is working for. A basic concept & critical technologies of VoIP including signaling, coding, Media Transmission Technology as well as Quality of Service Technology are first discussed. Then it follows with a discussion of the critical elements & typical VoIP deployment models of an entire VoIP Telephony system. Afterwards, the author designs and implements a VoIP telephony system using Cisco Unified Communication Manager and H.323 Gateway. At the meantime, the author also works out a general template for device selection, configuration standard & feature testing checklist.