GLOSSARY OF CONNECTIVITY
Your guide to Phone Connectivity Language
There are two sides when it comes to the voice communication of your business – the phone system (whether physically onsite with hardware or hosted) and the lines coming into the system.
Here are types of “lines” that range from older to newer. In each type of line below – keep in mind the terms call path and DID (direct inward dial) number. A call path just means how many total concurrent phone calls can happen from your business at one time (this means calls in from your customers and calls going out from your workers) and a DID is just the actual phone number you dial (example: the DataComm Plus main phone number is 262.784.2311).
You should be able to see the DID numbers you pay for from your connectivity provider on your monthly phone bill.
Types of connectivity:
- POTS (“plain old telephone service”) which is also known currently as analog or digital
These are the old-timey lines everyone first started off having – back when they were copper wires that fed into your building through the wall and connected directly to your phone system. Connectivity providers (the AT&Ts and Spectrums of the world) have the equivalent of this that are considered “digital” lines. You have as many “call paths” as how many analog lines you choose to add to your business. There is one DID per call path, but often a business only markets ONE primary phone number and the other call paths are put in a “hunt sequence,” so that if more than one person calls the main phone number, they can get through instead of hearing a busy signal.
- T1/PRI (primary rate interface)
A PRI is usually run off a T1. A T1 is a slightly older version of technology where the provider brought a fiber-optic line into the building and it is often carrying data which means it plugs into a network router (sometimes a T1 is brought in on copper). A T1 device can hold up to 24 channels or call paths. A PRI is like a T1, but has 23 channels or call paths and 1 channel is dedicated for the signaling between the network and the phone system and has some more advanced features like:
- Multiple DIDs – you could have a direct dial number for every person in the company (hundreds of DIDs if you wanted.)
- Voice, data (Internet) and faxing can be shared on a PRI depending on what makes sense for your business.
(Many providers will allow a “fractional” version of what’s above – so if you don’t need 23 call paths, you can request one with 12 or 8 call paths.)
- SIP trunks (session initiation protocol)
SIP trunks allow people around the world to communicate using hard desk phones, computers, tablets, smart phones or other mobile devices by running the voice call over the Internet and using the company’s bandwidth. The ratio is one call path to one SIP trunk, but like a PRI, there can be hundreds of DIDs pointing to those call paths. SIP trunks have additional advanced features like:
- Redundancy (if the Internet goes down, SIP trunks can be re-routed automatically to a hosted Auto Attendant or sent off to a cell phone.)
- DIDs that have area codes from all over the country (you could have a New York phone number that is routing to a phone system and being answered in Wisconsin.)
- Generally cost-effective, sometimes being around $15 per SIP trunk/month.
You hear the most about this type of call path when you’re discussing VoIP (Voice over Internet Protocol)