Thursday, December 17, 2009

How to implement Voip Service in Real Time?

The following are some requirements of a network to support VoIP service, which serve as important aspects to be taken in the IP network to implement Voip service in real time:

  • Manage requests RSVP is a resource reservation protocol.

  • The cost of service must be based on the routing for IP networks.

  • Where it connects with the public switched network, IP telephony switch must support the protocol of Signaling System 7 (SS7). SS7 is used effectively to wireless and fixed line calls on the PSTN and to access the database server to the PSTN. The switches support SS7 in IP telephony is an important step in the integration of PSTN and IP data networks.

  • Must work with a comprehensive set of standards telephony (SS7, Recommendation H.323) to IP telephony environments and PBX / PSTN / ATM video telephone and Gateway can operate together in all its features

Voip Phones - Factors for Quality of Service (QoS)

Signal delivery of voice, video and fax from one point to another cannot be considered done with complete success unless the quality of signals transmitted meets the receiver. Among the factors that affect quality include the following:

Bandwidth requirements, the speed of transmission, network infrastructure, and its physical topology for Voip Phones.

  • Control Functions includes the reservation of resources, provision and monitoring required to establish and maintain multimedia connection.
  • Latency or delay from source to destination of the signal through the network.
  • Jitter variation in arrival times between packets. To minimize this factor incoming packets are to be placed in a buffer and from there sent to standard intervals for Voip Phones.
  • Packet loss: When a packet video or voice is lost in the network must have some kind of compensation of the signal at the receiving end.

Advantages of voice over IP technology

* Include on your intranet as a voice service over its network, as other IT services.

* The network IP networks are universal standard for the Internet, intranets and extranets.

* Standards effective (H.323)

* Interoperability of different suppliers

* Use of existing data networks

* The independence of transport technologies (layer 2), ensuring investment.

* Lower cost alternative technologies (voice over TDM, ATM, Frame Relay)


1. the voice and data networks are essentially different. The voice and fax networks, which use circuit switching, are characterized by:

* To start the connection establishment must make the call.

* Reserved network resources throughout the duration of the connection.

* It uses a fixed bandwidth (typically 64 Kbps per voice channel) that can be eaten or not, depending on traffic.

* Prices are usually based on time of use.

* The suppliers are subject to industry standards and regulated and controlled by the relevant authorities (in our case, the Ministry of Development and Market Commission of Telecommunications).

* The service should be universal to all the state level.

* By contrast, data networks based on packet switching, are identified by the following characteristics:

* To ensure delivery of required routing data packets, without requiring the establishment of call.

* The consumption of network resources is done according to need, without, in general, be reserved following a criterion of end to end.

* Prices are formed solely on the basis of competitive tension in supply and demand.

* Services are provided according to the criteria imposed by demand, varying widely in geographical coverage, speed of the technology used and conditions of service.

* Deploying a converged network involves studying the differences between the characteristics of voice networks and data, understanding the technical problems involved in such differences without losing sight for one moment the end user perspective.