There are many different perspectives on VoIP (Voice over Internet Protocol) or IP (Internet Protocol) Telephony in the communications industry. These perspectives vary depending on what vendor or provider you are having the discussion with. There are a couple of different issues to keep in mind when planning any type of IP migration or integration. First and foremost is what terminology is used. In the simplest of forms, VoIP is the full transport of signaling and voice data over an IP Network. IP Telephony is the strategy that allows signaling only to be transferred over the IP Network. Secondly is to develop a strategy on how either or both of these technologies can be implemented while maintaining a certain level of redundancy and acceptable voice quality.
When VoIP first hit the headlines in the mid nineties, it was advertised as the end to long distance charges. Ten years later it is obvious that is not the case. Although they might have gone through some tough times, Long Distance Carriers still exist and everyone still pays long distance toll charges in one way or another. The truth is that when using VoIP in a capacity that transports voice over an unmanaged network with no Quality of Service (QoS), such as the Internet, the results are usually unfavorable. The reason for this is very simple. The way the Internet and the protocols that make it work were designed, there was no consideration for real time transport of media. Traditional voice is transferred over circuit switched networks that allows for a constant connection between two or more parties for the duration of a call. IP networks, such as the Internet are packet switched networks, which allows data, in the form of packets to be transported in the best route or routes available. So hypothetically a piece of data can be sent over the internet and the packets could be split up in a few different ways and arrive at the destination in a different order than it was originally sent out. Due to such things as packet headers and IP addressing this is not a problem in the data world because it is not real time. A piece of data, such as an email can be reassembled after it reaches its destination and appear perfectly normal to an end user. If we considered voice in the same fashion, what we would get is garbled speech and inaudible conversations.
The way the industry has helped this is by establishing a set of parameters to allow for Quality of Service. QoS encompasses many different techniques, some which may vary depending on your vendor. Two very popular ideas behind QoS are packet tagging and queuing. Packet tagging enables network appliances so they can assign certain priorities to different types of traffic. This allows voice or any other type of real-time traffic to be assigned a higher priority than non real-time such as data. Network devices read the packets and will send out high priority packets before the lower priority packets. This is done in conjunction with queuing. The queues are used so the packet waiting have a place to “wait in line.” When considering VoIP and speaking to your technology vendor, make sure they have an established and proven way of doing this effectively.
Now, what are the advantages? When speaking about full VoIP a very viable benefit is Toll Bypass. For companies that have more than one location and place a lot of calls between sites, a VOIP solution might be the way to go. The most important thing is that a company has a data network that can handle the additional traffic. More times than none, a data network has a lot of older technology that might need to be upgraded to support QoS and the higher bandwidth needed to compensate for the additional traffic. Besides Toll Bypass, IP Telephony itself has tremendous benefits. It gives us the ability to connect remote offices so they function as one “Converged Enterprise.” An employee that works in an office on the West coast can now dial four digits and call someone on the East coast.
The possibilities are endless, but due diligence and planning need to be done before time. Deploying this in your company having to go back to the drawing board can be disastrously expensive. This cost can decrease the rate of your ROI by years. Interview your vendors and find someone you can trust. References as always are a must!