Upgrading? Understand Your trunking Options.
When you are looking for a new phone system, one of the first questions you are asked is “What kind of trunks do you have?” Much of the time the response is “what are trunks?” Put in laymen’s terms, trunks are the means in which your phone system communicates with outside world. It is your dial tone. There are generally three groups into which we classify trunking, and each have pros and cons. We will briefly discuss them.
POTS Lines
In the old days you pretty much had one standard trunking solution which was a pair of copper wires, which we call POTs lines, or Plain Old Telephone Lines. Anyone who has had a land line at their house can relate to this type of line. Two wires go from your house to the central office of the telephone company and then are routed to another pair of wires when you call another subscriber. The main difference with businesses is the need for several of these lines so their employees could make and receive simultaneous calls. Having these multiple lines required a way to integrate them into the business, which was largely done by a telephone system. There are still many of these lines in use today, although many of these “POTS” lines are now just simulated by digital devices. The days of true analogue lines are gradually going by the wayside, and AT&T has vowed to phase them out over the next 7 years or so.
What are the pros of POTS lines?
For the small business with limited access to high speed data, the POTs line is still an effective solution. Although they are gradually being replaced by SIP solutions, they still have physical connections which afford a somewhat more consistent reliability being that the local phone company still maintains them directly.
What are the cons?
POTS lines are slowly being phased out since they are outdated technology. Those hanging on to their old phone systems are going to have to upgrade sooner rather than later. These lines are also more expensive, and if high bandwidth Internet is available which allows for the utilization of SIP trunking, you can decrease your telephone bill by 50% or more. Also, many POTs lines are not physical copper lines anymore, and are digital interfaces which are converted to an analogue interface on the phone system. This conversion also means there can be loss of call quality. As technology advances POTS lines are going to be a thing of the past. Purchasing a phone system that is designed as a TDM system and requires POTS lines is obviously a poor investment. Your investment dollar is much better spent with a system that fully embraces the next generation technology; avoid systems that are designed around the old technology.
PRI/T1 Trunks
The PRI/T1 interface has been around now for some time. Once only utilized by large businesses because of high cost, they are now found in businesses of all sizes. A PRI is a digital circuit which runs on 2 pairs of wire and delivers 24 channels, one being used for negotiation. The other 23 channels are channels used for voice lines, giving a PRI a robust 23 voice channels. There are also shared T1s which can also be used for both voice and data. This however s not utilized so much anymore since a whole T1 is only 1.54 Mps.
What are the pros of the PRI?
A PRI can still be very cost effective voice solution for your business. With the cost averaging between $350.00 to $450.00 a month for 23 lines, a PRI can make a lot of sense. Maintenance on the PRI is also usually easier to manage since your provider maintains it up to the telco demark, and your phone vender is responsible for it after that point into the phone system. Call quality is usually consistent on a PRI. For businesses with a lot of DIDs and the need for several phone lines, a PRI is a viable option that will be around for the foreseeable future, yet will be losing market share to SIP trunks..
What are the cons?
Although the cost on a T1 has come down over the past 10 years, it can still be a bit much for those business that do not need 23 lines. It also costs your business more to interface a PRI into the phone system since it requires a PRI interface card. This makes the PRI perhaps a bit much for the business that may only need 10 phone lines for example. With all of the service provider consolidation happening in the industry, T1/PRI providers are being acquired by a few large companies. This has had the effect of reducing customer service to very low levels in some areas. Make sure to take this into account with your vendor. The T1 and analog service providers are in a diminishing business sector. They are rapidly losing market share to the SIP providers. This trend will not be reversed.
SIP trunks- The Wave of the Future
SIP (Session Initiation Protocol) trunking is the new kid on the block compared to POTS and PRI solutions. It utilizes the Internet to make voice over IP phone calls. A PBX that is SIP based only needs an Internet connection with adequate bandwidth to utilize SIP trunks. Essentially the IP-PBX hangs on your local network which is connected to the Internet. This allows your IP-PBX access to set up VoIP calls. I would make sure that whatever system you buy has SIP compatibility, and even better if the system is SIP ready out of the box. Watch out for systems that have SIP licensing as an add-on. SIP trunking is becoming an extremely popular form of trunking and appears to be the way communications will move in the future. New looking systems with a TDM core instead of a true pure IP PBX may be something to avoid, as they may become obsolete as parts become scarce and the old technology is displaced by IP PBX systems that are software based.
What are the pros of SIP?
SIP trunks are a very cost effective way to bring dial tone into your business. They are somewhere around 50% less expensive than POTS lines, and often include great long distance plans. This can mean huge monthly savings on your phone bill. They are fairly easy to integrate into the phone system and there are many companies to choose from. You can also choose how many SIP trunks you need based on your business traffic and you can add them easily as you need them. SIP provides you with the best scalability. SIPs also provide the best redundancy since they can be utilized with a Cloud in the event that your premise based system crashes and your Internet is still up. VoIP call quality when set up correctly is very good. As the “new kid” on the block, SIP carriers are much more customer centric than the old wire line carriers, hence customer service is essential to be competitive in this growing sector.
What are the cons?
SIP trunks are still new technology and bandwidth plays a critical role in having call quality. Depending on how many simultaneous calls you need, you must calculate then needed bandwidth and make sure your slowest speed will suffice. Companies that have only DSL speed may have problems depending on their need. Maintenance is also sometimes a bit more difficult to deal with since you have more parties involved. You not only have the SIP provider, but you may also have a different Internet provider to work with as well, which can directly affect the quality of SIP trunking.
Summary
Depending on your business’s situation and needs, any of the above trunking solutions may be utilized. There are some areas where you have no viable option other than to use POTS lines. However, as Internet service becomes more popular, and higher speeds and reliability increase, so will SIP trunks. The PRI is a nice way to go if you need several lines and want maximum stability. Finally, I would always encourage using more than one trunk solution for redundancy. Even if you only have a few SIP trunks, I would recommend complementing the traditional PRI or POTS lines with SIP. Your premise based IP-PBX provides your business with the best redundancy when it comes to trunking. I recommend buying a system that will grow tih you on the SIP side of things, and systems that are SIP ready with no additional licensing for SIP trunks wil be the most cost effective. I hope this information helps you when you go shopping for your next phone system.
