Voice Over IP Pros and Cons
With the evident technical limitations of implementing Voice Over Packet-Switched IP networks, why does VOIP technology still deserve consideration? The answer lies in the many advantages offered by the new VOIP products and services. Nevertheless VoIP also has disadvantages, which are the main cause for which VoIP is not yet the common way to communicate between people.
In this section we will try to explore these advantages and disadvantages.
-
VoIP is cost effective - using VoIP products long distance phone calls and international calls can be made within the price of a local call. The caller simply connects to the Internet (with the price of a call to his local Internet provider) and using the appropriate software, calls other computers running similar VoIP applications, or even other telephones anywhere in the world. (Performing a PC-2-Phone conversation requires a VoIP Gateway to be present at the remote location)
A growing amount of communication operators throughout the world utilize VoIP as the modern communication method for long distance calls, enabling a full Phone-2-Phone conversation, which is carried over an IP network. (Fully transparent to the caller) Using the IP networks for voice transportation allows for a greater deal of phone calls to be made simultaneously, thus reducing the operators' costs.
Furthermore, large companies can use their intranet as their internal enterprise phone network (iPBX). This enables lower maintenance fees, and cheap communication to remote sites and branches of the organization.
- Convergence - By using VoIP, a company can have one comprehensive solution handling both data and telephone communication, all on the same platform and supported by a single vendor. This allows companies to use a single system for all their communication needs and prevents the overhead caused when dealing with several software packages and platforms.
- Scalability and interoperability - Due to the fact that IP networks are scalable in their essence and wide spread, VoIP based solutions can be quite easily scaled whenever necessary. Connecting VoIP networks together can be done easily, with minimum effort put into the process.
Maintenance (Upgrades to existing services or introducing new services) can be easily done, as most applications are actually software based and do not require any hardware replacements and configuration.
- Smart Net - Being software based, VoIP products and services enable various smart solutions. Achieving the same management capabilities on standard PSTN requires substantial hardware changes whilst most of the VoIP solutions can easily managed by a click of a mouse. An example could be the routing of a phone call to a subscriber in a predefined way: a schedule is set, and all phone calls are diverted to different locations (e.g. Home, Cellular, Business, Voicemail) according to this schedule. Performing this capability in VoIP networks is trivial (Software solution), while achieving the same functionality on standard PSTN requires a great deal of effort.
- New age multimedia - Because we treat voice as data and due to the fact that we can use voice services and telephony services from our PC, We can use voice applications as another application on our computer. In that way we can use the same hardware to browse the net, talk over the phone and work on other applications at the same time and without having to switch between devices. This idea is also part of the convergence advantage that was brought up here in this section.
- Evolution towards better communication services - For all the reasons mentioned above, VoIP is an evolution towards better communication services. We can combine voice with streaming video for conference calls, allow better multimedia by using all sorts of web applications and offer customers with better communication services (such as the smart net) in order to get a communication package that will be adjustable and will be configured to supply every customer needs.
-
IP networks were originally designed for data transfer, without any consideration for the need for real-time transportation of voice packets. Due to this fact, VoIP faces some difficulties when running on such networks.
- Network delays - Delays occur in IP networks due to the very nature of data communication. Insufficient bandwidth can be a problematic factor for VoIP, when the traffic on the network is heavy, and there is a continuous struggle between voice and data packets. For that purpose exactly, new switches are beginning to emerge that support QoS. Those switches are able to prioritize each packet, thus giving ongoing VoIP calls' packets a high priority in the overall traffic. This, however is not sophisticated enough, and the work of improving the control over the network traffic is happening as those words are written.
Long delays usually tend to occur when the voice transports over a public network as those are often crowded with traffic, and there is less control and priority for voice packets. In intranet networks, this problem rarely occurs because its operators has better control on the network.
- Jitters - In packet-based networks, two packets sent from the same source to the same destination might take different routes through the network. This is because the packets are routed through the network independently. Hence, two packets between the same source and destination might experience different processing delays and different congestion situations in the network, resulting in a variation in the overall delay experienced by the packets. This variation in the delay experienced by packets is measured as delay jitter. Also, this might lead to packets reaching the destination out of order. Unlike data packets, voice packets would be severely affected by the delay jitter.
- Cost - As always, the main disadvantage of a new technology is its initial cost, wireline communication is very cost effective because almost all the R&D have been completed in the area, the infrastructures are already built, and the public is used to using this type of media. In order to use the VoIP more often, costly changes will have to be taken: Stronger and more reliable networks will have to be built (Better bandwidth, better QoS compliance), new products and services will have to be developed and the main issue - people will have to become aware of this new technology and start using it more often. For the VoIP world to flourish, it has to be cost effective, provide better functionalities as well as maintain the current PSTN reliability.
