What is the Infrastructural Demand for VoIP?
Networks today are shifting more information than ever in the mode of bandwidth-intensive, instant voice, data, and video, which stretch network resources and capabilities. Cisco IOS software provides QoS VoIP solutions that aid to solve problems created by ever-increasing traffic hassles on one network.
QoS VoIP pertains to the ability of a network, whether the network is a multifaceted network, small corporate network, enterprise network or Internet service provider (ISP) to offer improved service to selected network traffic over a number of technologies, including Frame Relay, Ethernet and IP-routed networks that may use all of these essential technologies.
The prime goals of QoS VoIP are to supply better and more conventional network service by offering dedicated bandwidth, controlled latency, and jitter, as well as increasing loss characteristics. QoS VoIP accomplishes these goals by providing tools for managing network congestion, shaping network traffic, using expensive wide-area links more efficiently, shaping network traffic and setting policies across the network.
It should be noted right away that IP telephony does not always require an Internet connection. For example, the company’s internal telephone network can be organized directly on the basis of IP PBX, and accordingly, internal calls will be made via IP telephony. For calls outside the office to mobile numbers, it’s enough to connect the GSM-gateway, and for calls to city numbers you can connect existing analog telephone lines via FXO-gateway or existing PRI stream.
Still, consider the classical use of VoIP telephone calls. In this case, the main condition for the organization of IP-telephony is the availability of an Internet channel. The Internet channel can be either dedicated (wired) or wireless (wireless). Ideally, there should be both a wired and wireless Internet channel, because The continuity of their work depends on various factors. In this case, the Internet channel must meet certain requirements, because It depends on it, how high-quality will be the telephone communication in the office.
Requirements for the Internet channel of IP telephony:
1. Delays in the transmission of packets are not more than 50 milliseconds (in some cases, some services automatically exchange server keeps the connection for delays in the transmission of packets up to 1500 milliseconds).
2. Packet jitter is not more than 20 milliseconds.
3. The width of the Internet channel is not less than 100 kbit / s, calculated for one telephone conversation.
4. For IP telephony, it is desirable to allocate a separate Internet channel or to separate it from software and hardware into a channel for telephony and a channel for Internet surfing.
5. It is preferable to have a static external IP address because Some telephony operators can not connect SIP numbers to a dynamic IP address.
6. Availability of a backup Internet channel (recommendation).