February 1, 1999
What’s at the End of the Pipe: A Primer
By Kieren McCobb
Most telecommunications services marketed by agents plug into some type of voice or
data equipment, or "box." The agent who wishes to stay in business and grow
needs to know and understand these systems. The following is a primer explaining the types
of voice and data equipment that’s at the end of the pipe.
For simplicity, these are described separately below, but note that there is some
crossover between voice and data systems. For example: The T1 your customer installs for
dedicated access to your long distance carrier’s point of presence (POP) plugs into a
channel service unit/data service unit, (CSU/DSU). In this case, the box serves a voice
function. If the T1, or some of its channels, is used to transmit data, then it is serving
a data function.
Voice Communications Equipment
All agents have been in situations in which they had a price advantage on part
To keep things simple we will assume there are two kinds of telephone systems: private
branch exchanges (PBXs) and key systems. You occasionally will hear a PBX referred to as a
"switch." There was a time when the distinction between the two was clear, but
as with so much else in the 1990s, telling them apart has grown a little more complicated.
Generally, a PBX is bigger–meaning more lines or phones and more trunks–and can do more
(i.e., it has more features). Typically, users need to dial "9" to make a call
on a PBX but press a line button to make a call with a key system.
Long distance agents need to know about a feature in most PBXs and some key systems
called least-cost routing (LCR) or automatic route selection (ARS). This feature routes an
outbound call attempt over the least expensive facility available at that moment in time.
It does this because it’s been programmed to do so by your customer’s telecom manager or
the customer’s vendor. This is important because some carriers have great interstate rates
and miserable intrastate rates, or vice versa.
The phone system then will send the call over the carrier facility with the economical
interstate rate, if the call is interstate. But if it’s going intrastate, the PBX will
attempt to route the call over the facility best for that type of call. The telephone
system reads the area code/exchange combination (NPA/NNX); this is called six-digit
screening. The system then looks to see what facilities are available and sends the call
out over the most economical carrier available at that moment in time.
All agents have been in situations in which they had a price advantage on part but not
all of a prospect’s business. Understanding LCR will win some percentage of those
otherwise-lost deals. How do you know if the customer has LCR? Ask him or her, or offer to
call his or her equipment vendor and ask about this capability. It will set you apart.
Key systems generally are smaller phone systems, meaning less phones and trunks. They
may not have every feature that a PBX has, but the gap has narrowed considerably over the
years. Again, the main thing to look for here is LCR capability.
Voice Processing Systems
Voice mail is the bane of dinosaurs and fossils everywhere. Like it or not, it’s here to stay, and when used properly is a great tool. You may wish to suggest your client put in a toll-free number, unpublished, that rings into the pilot (first) number of the voice mail group of lines. Only employees know this toll-free number. This way, people can check their messages more quickly and less expensively than using a calling card.
Automated attendant is the software that allows callers to route themselves to the desired department or extension. Your customer may consider putting in a number, not necessarily toll-free, that allows callers the option of routing their own call. Some callers will like it and use it; others will continue to use the traditional number. The benefit to your customer is relieving some traffic from the main answering point.
Interactive voice response (IVR) and automated call distribution (ACD). You may recognize IVR as a banking application and ACD as an airline application. ACD is used in call centers, meaning heavy traffic, usually inbound, to a group of people taking those calls. Frequently, these centers have more trunks than people to answer the calls. So a machine answers the calls, a greeting message is played and the call is queued for answer when an agent becomes available. Every step of the call is tracked and information generated about the call from beginning to end. Management makes decisions about its business by paying close attention to the information provided.
By no means are these the only industries that use the technologies, however. IVR
"marries" voice processing with the customer’s computerized database. IVR
frequently is used along with ACD these days. What IVR and ACD say to the savvy agent is
"lots of incoming calls" and "heavy need for reliability." This type
of customer is one who will say, "I’m not just interested in the cheapest
price." They also are huge users of telecommunications services, including long
distance. Selling this type of account is the grand slam of long distance and will take
knowledge, patience and hard work. And it’s worth it.
Data Communications Equipment
Private lines and data services are the holy grails of our business, and most agents
are afraid of them. Make no mistake–selling these types of services will decide who is
still in this business three years from now. These services are far less complicated than
agents think (see the Agency columns in the October 1998 and November 1998 issues of PHONE+).
Following are the most common types of data equipment:
Modems can be confusing for agent and customer alike. Steve Hesling at American Telesis points out that many agents and customers alike are unaware of different modem types. A big distinction needs to be made between the common asynchronous dial-up modem and the analog private-line modem. The dial-up type is the common modem found in personal computers (PCs), fax machines, etc. When you have an analog private line, however, you need an analog private-line modem. It’s designed for circuits that are "nailed up" or always "on." Be sure your customer gets the correct type.
A CSU/DSU plugs into the jack in which your local exchange carrier (LEC) installed its T1 or 56-kilobits-per-second (kbps) circuit. Then it goes into the PBX (for voice) or the computer equipment (for data). This device does some conditioning and monitoring functions on the line and allows the capability to do a "loop-back" test, so diagnostics can determine failure to the line or the equipment.
Recommend to your customers they buy dial backup capability on the CSU/DSU. This ensures the plain old telephone service (POTS) line is available for automatic dialing to the other site when the 56kbps or T1 circuit goes down. With this feature the customer maintains connectivity, albeit much slower. Although this auto-dial backup is a nice feature, the CSU/DSU may not automatically reconnect the digital line once it is repaired, so customers need to be reminded proactively to reset the CSU/DSU to the 56kbps or T1 circuit. If they don’t, they could get a phone bill for a month’s worth of expensive calls! Remember, it’s a dial backup.
A multiplexer, sometimes referred to as a "mux," is a box that aggregates channels or signals to be sent across a circuit. On the receiving side, a mux accepts that circuit and cuts the circuit back into channels or signals.
A channel bank is similar to a multiplexer, and frequently they are used interchangeably. It takes a T1 circuit from the LEC and cuts it into its 24 channels, and is often used with less-modern PBXs that are incapable of accepting T1 directly into the PBX.
A digital trunk interface (DTI), or DTI card, also eliminates the need for a channel bank.
The device installed at each node of a frame relay network–and, occasionally, certain other types of networks–are called routers. Routers find the best way between networks among multiple choices.
Kieren McCobb is president of TeleConfusion Removal, a consulting firm serving
telecommunications agents. He also is president of AIB Communications Inc., an authorized
Bell Atlantic Corp. agent providing T1, primary rate interface (PRI), DS-3, frame relay
and Centrex offerings to end users in the Northeast region. He can be reached by phone at
+1 732 249 2821 and by e-mail at [email protected].
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