One thing every business, large or small, needs is at least one telephone line. Phone lines may seem pretty mundane, but you may have more options than you think. Are you sure that you have the right phone line for your business?
Plain Old Telephone Service
The historical phone line that we’re all familiar with is the analog phone line, also called POTS for Plain Old Telephone Service. It’s that vanilla.
POTS lines are as simple as they come. They consist of a single twisted copper pair that runs from a standard RJ-11 phone jack on your wall all the way back to the telephone company central office. The phone conversation is carried by a varying current in the wires.
What you may not realize is that POTS is a self-contained phone system. Phones were traditionally made of passive electrical components. They got their power right off the phone line… and still can. The value of this is that even if the electrical power goes off at your location, you still have phone service.
What’s happened lately, however, is that even single line phones have gone electronic and require AC power supplies and/or batteries to power the circuitry. This is especially true of cordless phone systems with multiple handsets. You can still get dial tone during a power outage, but you need to have a backup battery supply to operate the phone, not the line.
You are not stuck with just a single POTS line. You can have as many as you want. Mind you, there is no economy of scale. There is a fixed price for each line whether you have one phone per line or share the outside lines using a Key Telephone System or PBX.
Wireless as an Option
Can you get rid of the telephone line completely? That’s what cellular phone service is all about. No more “landline”. Everything is done with cell towers instead of wires. Wireless can work just fine for independent professionals who are always out of the office anyway. With a data plan you can have both Internet and voice telephony on the same device. You can enhance your mobile setup with an incoming toll free number, fax transmission and reception, and international dial-around calling. Shared plans can support a small office as well as a single user. Operations larger than that will still need wired landlines.
Moving up to Trunks
A telephone trunk is multiple phone lines coming in on a single cable. There used to be analog trunks, but that technology has all gone digital. The most popular trunks are T1, ISDN PRI and SIP.
T1 lines were devised as replacements for multiple analog POTS lines. Instead of separate wires, T1 lines are multiplexed to divvy up the available bandwidth into 24 independent channels. Each channel can be thought of as a separate phone line.
What if you already have a dozen phones and want to replace all those separate phone lines with a single T1 line? Chances are that you’ll get the same or better service at a lower monthly cost. A box called a “channel bank” handles the conversion between T1 channels and analog lines. Just plug your phones in like you always have.
T1 vs ISDN PRI
ISDN PRI or Primary Rate Interface is a variation on the T1 line. It uses the same channelization scheme, but dedicates one channel to dialing and switching for all the others. That means you have a maximum of 23 outside lines available on a PRI trunk. The tradeoff is that your phone calls will switch faster on ISDN PRI. That’s important for call centers and others who need highly efficient telephone operations.
Most PBX systems now have the interface circuitry for T1 and ISDN PRI already built-in. You simply plug in the trunk line and the system handles all of the necessary conversions.
Many, many companies are considering switching to VoIP technology or have already made the move. SIP trunks are the natural complement to VoIP phone systems. Their advantage is that they use the same protocol, SIP, as the phone themselves. Remember that VoIP or SIP phones connect directly to an Ethernet LAN, usually shared with computers, printers and other network devices. The SIP trunk extends the network so that it also connects to the VoIP service provider.
Like T1 and ISDN PRI, SIP trunks support multiple simultaneous telephone conversations. The difference is that these conversations consist of packet streams all combined on one line instead of breaking the line into separate channels.
Another advantage of SIP trunks is that they can carry Internet traffic as well as phone calls. After all, everything is in packet format. What’s important is that the trunk be setup to prioritize telephone traffic over data traffic to ensure voice quality. This is called Class of Service or Quality of Service.
What phone line is best for your business? One way to find out quickly is to get multiple competitive quotes for everything from POTS through SIP Trunking as business phone line options.