Telephone Trunks for Call Centers

By: John Shepler

All businesses need telephone lines of some sort. Independent professionals may rely on a smartphone for wireless communication, but businesses with offices or stores open to the public or with two or more employees almost always have some sort of landline installed. Let’s take a look at the analog and digital options available and the advantage of installing telephone trunk lines to increase capacity and reduce cost.


Plain Old Analog
Analog phone lines are the legacy technology of the phone companies going back over a century. You’ll hear them described as POTS or Plain Old Telephone Service. POTS lines are well established, highly reliable and engineered for high voice quality on both local and toll calls. Standard phones, including desk sets and cordless phones with multiple handsets, are analog phones and plug directly into analog business phone lines.

Broadband Phone
The digital solution for a single phone line is a broadband Internet connection shared with the computers. This option is usually chosen for its low cost, but voice quality can degrade and certain applications, like FAX machines and alarm systems, may not function correctly.

Adding More Lines
What about the vast majority of businesses with more than one phone line, especially those with an in-house contact center or specializing as a call center? Small operations sill rely on analog phone lines. You can add analog lines one at a time and plug them into your key telephone system or PBX switching system. Each outside line has its own phone number.

How Costs Add Up
Adding analog phone lines incrementally as you need them works well until you get more than half a dozen to a dozen separate lines. There are no technical issues, but costs mount up. Two lines cost twice as much as one line. Six lines cost six times as much. There is no economy of scale as these are independent lines.

How Trunking Saves
The strategy for reducing costs while maintaining voice quality and reliability is called trunking. Trunking simply means combining multiple lines to create a single trunk line with the same capacity. Trunking was invented by the telephone industry to transport dozens or even thousands of phone conversations efficiently from switching office to switching office. Originally, this was done with analog technology called carrier telephony. In recent decades, it’s all gone digital from office to office, leaving analog POTS lines only for that last mile connection between the telco office and the customer’s premises.

T1 Telephone Trunks
The first digital trunk line that was introduced by the phone industry for business users was the T1 telephone line. Yes, this is the same T1 technology that you may be using for point to point or dedicated Internet access. The difference is that the T1 line is divided or “channelized” into 24 separate segments or time slots. Each channel can transport one two-way telephone conversation and is the equivalent of an analog POTS line. You can use an appliance called a channel bank to convert between analog phone and the T1 line. Most in-house PBX phone systems have the necessary interface to do this or it can be added easily with a plug-in card.

Cost Advantage of T1
The big advantage of T1 trunks is that they become cost competitive with multiple POTS lines when you get over 6 to 10 outside lines. If you need more than a dozen phone lines for your desks or a call center operation, T1 is the lower cost option. Multiple T1 lines can be added to provide blocks of 24 outside lines incrementally.

ISDN PRI Improves on T1
A newer version of the T1 line is called ISDN PRI or Primary Rate interface. It uses the same T1 line but reserves one channel for signaling and switching. The other 23 channels are available as separate phone lines. ISDN PRI is popular with call centers because it provides faster call setup and teardown than the older T1 telephone lines. It also offers digital data ,such as Caller ID, that is not generally available on just T1 trunks. Like T1, though, multiple ISDN PRI trunks can be installed to provide as many outside lines as needed. Cost is competitive with T1 and most PBX systems come with the PRI interface already installed.

SIP Trunking, The Emerging Standard
While ISDN PRI is now the standard in commercial telephone trunking technology, an even newer technology is available to better support enterprise VoIP telephone systems. This is called SIP trunking. SIP is the switching protocol used by IP telephones and VoIP phone systems.

SIP vs T1
SIP trunks are also digital, but differ from T1 lines in that they are based on packet switching rather than time division channelization. Packet switching is the heart of all Ethernet networks that support computing. What companies are doing is replacing their old analog telephones with IP phones that connect to the same network as the computers. SIP trunks extend this connection out to the service provider for multiple telephone lines or a combination of voice and data.

Private Lines vs The Internet
Note that high performance SIP trunks are private lines between the user and the carrier and do not suffer from the vagaries of Internet broadband phone. SIP trunks often have the ability to also supply Internet service, but the telephone packets have priority to maintain high voice quality. SIP trunking is becoming popular for call center operations as companies replace their old PBX systems with newer IP PBX systems or choose to outsource the switching function to the cloud.

How to Choose
Which type of telephone trunking arrangement is optimum for your organization? Get some expert advice on the tradeoffs and competitive pricing from multiple carriers serving your location. Call now toll free (888) 848-8749 or enter your inquiry at Telexplainer.net

Can Hosted Voice Cut Your Phone Costs In Half?

A generation ago, a big cost savings opportunity was switching to a competing long distance telephone service provider. Both businesses and consumers went on a stampede once deregulation opened the door for competitors to the incumbent local phone companies and their lock on long distance prices. The real enabler was making the process all but invisible to the customer. Sure, there was some arcane procedural work involved in having your 1+ calls go to supplier B rather than supplier A. You didn’t have to deal with that. You simply called your new provider, fill out some paperwork or signed up online. The magic happened in a week or two and, suddenly, your long distance bills were lower.

There’s another stampede building right now. It’s the opportunity to move from the in-house phone system with trunk lines to the local telco to cloud hosted telephone services. In a way, what’s happening to local business telephone service is what happened to long distance decades ago. It’s moving to a lower cost model via disruptive technology. What will turn it into a full blown stampede is providers who make the move painless for their customers. Think about it. If you can cut your total phone costs in half without having to go through a gauntlet of technical gymnastics yourself, how can you not make the move?

Megapath, a full-service competitive telecom provider, is doing its best to become your next telephone company as well as your network services vendor. They’re doing this with a comprehensive hosted voice platform that makes it easy to get the phone services you need without YOU having to make the investment, develop the expertise or provide the staffing.

Just what is hosted voice and how can it offer such dramatic cost savings? It’s a matter of economy of scale. Every business can go out and buy a PBX switching system and a truck full of phones, wire all this up and bring in local dial tone with a bunch of POTS lines or an ISDN PRI trunk. Isn’t this pretty much what everyone has done? The alternative is to have a specialized service provider build a much larger switching system and the staff to run it and have companies who are not in the telephone business get their services remotely.

Hosted voice is a lot like website hosting in that instead of you maintaining your own servers, you pay by the month for someone else to provide the servers and the bandwidth that connects them to the internet. With hosted voice, you pay by the month for MegaPath or another hosted voice provider to switch all your in-house, local and long distance phone conversations and provide the telephone trunks that connect to the public phone system.

WIth hosted voice, there is no need to buy or maintain a local PBX phone system. You don’t need to lease any telephone lines. Whatever PSTN (Public Switched Telephone Network) connections you need will be provided. All you need are IP phones connected to your network and a voice gateway that that manages bandwidth to your service provider to ensure that voice quality has priority over other traffic. Capital investments are a thing of the past. You buy phones as you need them and you might even get the phones included free with your service plan.

It might not be immediately obvious that hosted voice with pay-as-you-go pricing has a flexibility that in-house systems lack. There is no need to buy more capacity than you can use right now. If you need 25 phones, then 25 phones and the service to run them is all you order. If you land a new contract and have to start hiring like crazy, then you go ahead and add “seats” to your system as needed. You pay incrementally more each month to match the increase in your business. You don’t go out and buy a big switching system to handle anticipated needs. The hosted voice provider has a system that can accommodate any possible number of phones you’ll ever order. That reserve capacity is something that works to your benefit but you don’t have to pay for.

The days of every company being in the telephone business are about over. The rise of hosted voice systems connected by SIP trunks, basically high bandwidth dedicated lines, enables a new model of telephony where you simply pay for what you need when you need it. Could this approach offer advantages for your company? Get competitive quotes for Hosted Voice Enterprise VoIP Telephony and compare them to your current costs, including what you have to invest in equipment and maintenance. It may be time for you to make the move to a hosted phone system.

Types of Business Telephone Lines

Business telephone lines, once available in only a single analog version, have proliferated over the years. You can still get the legacy analog subscriber loop. You can also get a variety of digital lines and trunks that may offer cost and performance advantages.

The basic business telephone line is little changed from its invention over a century ago. It consists of a single small gauge twisted pair copper wires that carry all the necessary signals. This is an analog telephone line. Analog phone service is also known as POTS for Plain Old Telephone Service. Many businesses have multi-line phones, but all they do is connect to multiple POTS lines. One to four lines is typical of a small office phone system. If there are lighted pushbuttons for each outside line, this may be called a “key” telephone system.

POTS telephone lines generally include local and long distance calling, features such as Caller ID, 3 way calling, and perhaps a toll free number. One POTS line may be connected full time to an office FAX machine. Some companies that have digital telephone systems may still keep a POTS line for the FAX machine, as not all digital services support FAX.

The simplest digital phone line is a single VoIP or broadband phone service that uses the Internet as a substitute for the twisted pair analog phone line. The cost savings realized is due to the fact that most businesses need broadband Internet access as well as telephone service. Using the Internet to connect the phone to the service provider avoids the charges for a separate telephone line.

The main limitation to broadband phone service is that the Internet was never designed to support high quality two-way real time voice or video services. It is critical to have enough bandwidth to support all the voice and data traffic on the broadband connection and to give voice packets priority. When bandwidth becomes restricted, voice quality starts to get garbled and the call may even be dropped. Another factor is latency or time delay between source and destination. The longer the latency, the more the phone starts to act like a two-way radio where only one person can talk at a time. Latency is seldom, if ever, a factor on analog lines or carefully engineered private networks.

Enterprise VoIP systems, consisting of many telephone sets connected to a converged voice and data LAN, avoid the limitations of the Internet by using dedicated circuits transport calls between internal phones and to the connection point or termination with the Public Switched Telephone Network. That termination may be within the company, where the connection is to multiple POTS lines or a digital trunk line. It may also be at a service provider connected to the enterprise by a converged voice and data line called a SIP Trunk.

A “trunk” line is simply a bundling of multiple telephone lines in one cable. That may be a fat cable with many analog copper pair or it can be a digital trunk line with few wires that transport many telephone calls in channels or packet streams.

The most popular digital trunk line is called ISDN PRI. This is also called T1 PRI because it is carried on a T1 digital line. What a PRI digital trunk gives you are up to 23 outside telephone lines plus a dedicated channel for switching signals and data such as Caller ID. Some PBX telephone systems have provisions to connect to two or more PRI trunks. This is especially true for call centers and large corporate office buildings. Note that each of the business lines in the ISDN PRI trunk can be configured as local, long distance, inbound only, outbound only, toll free or some combination of these per customer requirements.

The newest business telephone trunk is called SIP Trunking. SIP is the control and signaling protocol for VoIP telephone systems. One SIP trunk can carry dozens of phone calls, even more than a PRI trunk. The other way SIP trunks can be configured is for both voice and data on the same line. This is especially valuable for companies that have converged networks shared by both computers and telephones. The SIP services provider brings in both broadband Internet access plus business telephone lines on the same SIP trunk.

What type of service will work best for your company? There may be a range of options to choose from. Get prices and availability for business telephone service now, so you have up to date information to make an informed purchasing decision.