Voice over IP
Voice-over-Internet Protocol, Voice-over-IP, or more simply VoIP is a term used in telephony for a set of facilities for managing the delivery of voice information using the Internet Protocol (IP). It is a technique that allows voice traffic to be transported across an IP-based data network or the Internet. The voice signal is sampled, compressed and encapsulated into data packets to allow it to be switched, routed and bridged along with all other data packets across the Local and Wide area network.
Voice-over-IP comes from the VoIP Forum, a development by major equipment providers such as Cisco, VocalTec, 3Com, and Netspeak to promote the use of ITU-T H.323, the standard approved by the International Telecommunication Union (ITU) in 1996 for sending voice information using the Internet Protocol.
Internet Protocol (IP) is one of the many recognised standards over which data networks send data packets. Other popular protocols include frame relay and asynchronous transfer mode (ATM). When talking about VoIP there are two parts to the story: IP Trunking and IP Extensions.
IP Trunking is where multi-site systems transport telephone calls over their wide area network. The phones at each end don't necessarily have to be IP phones. IP Trunking is used to tie the two systems together. Voice effectively travels for free over the existing data network.
IP Extensions, or IP in the LAN, is where the extensions are IP Data devices working off the LAN. They can be multimedia softphones such as Net meeting, or alternatively IP telephones (IP Hardphone) which replicates a traditional telephone.
Voice-over-IP technology first created a buzz with the arrival of Internet telephony. Consumers got excited by the prospect of using a PC and an Internet connection to dial up friends anywhere in the world and talk for hours without ringing up long distance charges. However the products were proprietary and the quality of digital dialogue disappointing. However this said, the possibility of long-distance calls at local rates was enough to heat up the market. Companies of all sizes have since unleashed a flood of products, from PC software for end users to VoIP-PSTN gateways for carriers.
This sudden expansion of the market has resulted in substantially improved quality, raised the level of audio fidelity and strengthened support for industry-standard protocols. Voice over IP is now a serious consideration for any organisation evaluating its telephony and communications infrastructure.
Advantages of IP Telephony
Ubiquity
The IP standard is by far the world's most popular network protocol. It is developing fast and is accepted by every major vendor. Users can benefit from end-to-end connectivity to every data-networking device available, a tremendous amount of research from firms focused on IP, and a unique global addressing scheme which allows an IP device to address the entire network, regardless of size or location."
With more than 80 per cent of personal computers in business networks on a local area network (LAN), IP is an obvious transport of choice. It also seems to make sense to carry all forms of communication (data, voice, and video) over a common, ubiquitous medium.
Value Added Applications
Once an IP infrastructure is in place there is a seemingly unending number of add value applications that are available or being designed that are either far simpler than those enabled by regular telephony systems, or totally new applications like user registration that allows phone users to be identifiable and fully functional no matter which handset they're using.
Cost
For most large businesses, overhauling a PBX-based telecom infrastructure is a long-term investment decision. However, with telephony requirements becoming more demanding and new technology creating business advantage in shorter timeframes, IP telephony has become a more and more realistic alternative. And while cost projections will inevitably vary enormously from one company to another, most equipment vendors and IP telephony integration specialists would claim return on investment within one or two years.
Single Infrastructure
Putting the voice and data traffic on one set of wires instead of two also seems to make good commercial sense when compared to the cost of developing and supporting two separate infrastructures.
Overhead
A large part of that cost is a human one and again there is a clear case for creating one pool of skills rather than two, so that voice calls essentially become just another application running on the network. In reality the network will only see information packets, some of this information originates and terminates within a data edge device whilst other packets of information on the network will originate and terminate in voice edge devices.
Call centre
Several advantages arise from a Call Centre environment based on an IP infrastructure. Web based forms, text chat sessions, email, and web collaboration are all examples of modes of communication, which are based on the IP standard. Voice is transformed to the IP standard in IP call centres. An IP infrastructure therefore facilitates integration of both web-based media and voice into the call centre.
IP also puts companies in a better position to take advantage of future developments in terms of new channels because once an IP 'skeleton' is in place, functionality is just a question of what software is developed.
Key Considerations
VoIP remains a new technology and may not be in its own right the right answer for all organisations. Consideration should be given to the following:
Existing Communications Infrastructure Investments - most businesses have already made large investments in traditional voice-based telephony solutions therefore it is unlikely they will discard these to adopt VoIP without significant incremental benefit. IP-architecture is a major contender for new operations, but more established structures are more likely to attach and integrate VoIP to their existing voice-based infrastructure.
Quality of service - IP quality of service is still considered inferior to the proven reliable and robust traditional circuit-switched telephony - although this gap has closed significantly. Users within organisations deploying VoIP will have to get used to the internal phone system being inoperable should their internal data network falter.
Network issues - including interoperability, bandwidth management, security, packet loss, delays, interruptions and sound quality.
The need for en masse consumer adoption of VoIP communication devises. In organizations where there is significant customer contact both the consumer and the call centre personnel must have multimedia PCs or IP devices which have the required software and can send voice as data using the H.323 standard. This however can be overcome somewhat by switching technology which converts incoming voice to packet data and then back again on exit - however a fully IP architectured office is required.
As an organisation seeks to reduce rising communications costs, the idea of consolidating separate voice, fax, and data resources appears to offer the perfect opportunity for significant savings. Company's embarking on VoIP investment will want to evaluate the economic benefit of the proposed investment and determine what role if any their existing telecommunications infrastructure will continue to play.
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