30 Business Telecom Acronyms You Should Know

Ever been on the phone with your business internet or business phone provider and realize half way through the conversation that you start wondering when the other person started speaking Greek? The conversation starts out innocent enough with “high speed internet” and “unlimited usage”; those we understand just fine!  Somewhere along the way it takes a wild left turn and now we’re talking about ISDN … PRI … PBX … T1 … DIA – wait what??

Fear not – just bookmark this post and return to it whenever you hear an acronym you might not be sure of.  We’ll cover the basics here, so that you’re armed with the right tools and information to have an honest discussion with your service provider.

If you feel we’re missing an important acronym, leave a comment below and we’ll take a look!


bps/kbps/mbps/gbps – Bits, Kilobits, Megabits, Gigabits Per Second

These are data rate units, or rather how much data is transferred per second. If the b is lowercase it stands for Bit and if it’s capitalized it stands for Byte (there are 8 Bits in a Byte).  Typically when talking about internet, most carriers refer to their speeds in mbps or Megabits Per Second.  The higher the number, the more data can be transferred per second.

BRI – Basic Rate Interface

An ISDN configuration typically used for connecting your office to the Public Switched Telephone Network (PSTN).  Its counterpart, the Primary Rate Interface (PRI), is more commonly used.


CLEC – Competitive Local Exchange Carrier

A CLEC is a telecom service provider that is usually competing with existing (and usually much larger) telecom service providers.  Some examples of CLECs are XO Communications, Windstream, Broadview, and Cbeyond (among others).

CO – Central Office

A building that houses much of the local telephone exchanges for the area.  All phone calls to and from the surrounding areas pass through a Central Office.  This local exchange is usually identified by the first 3 numbers of the telephone number (not the area code).


DIA – Dedicated Internet Access

An internet connection that usually comes with a very specific bandwidth that is always available for your use, regardless of whether you use it or not.  This differs from “Best Effort” Internet Access which fluctuates in speed based on the usage of surrounding buildings.

DID – Direct Inward Dialing

This is your public facing telephone number that we all use to call each other.  For companies that have a Private Branch Exchange (PBX) you will typically have 1 main number for your entire company and a bunch of DIDs so that people can directly call individual phones.

DSL – Digital Subscriber Line

A technology used for transmitting data and internet access over the local telephone network.  Today DSL is used to connect people to the internet that don’t have a physical data connection or used as a backup in the event that the main data connection fails.


E-911 – Enhanced 9-1-1

A slightly more advanced version of 911 that provides not only location, but also identification.  As such, E-911 usually requires you to associate your ID with your phone number.  This is especially important for Voice Over IP (VoIP) Providers, since it’s not always easy to determine the location of a call originating over the internet.

EOC – Ethernet Over Copper

A technology for transmitting Ethernet data over existing copper lines (very similar to DSL).


FiOS – Verizon Fiber Optics

FiOS is the brand name that Verizon established to describe their transmission of voice, tv and internet over Fiber Optic cables.  Fiber Optics is one of the fastest and newest technologies for transmitting data.  While Verizon branded the term FiOS, other carriers are starting to deliver services via Fiber Optics.


GUI – Graphic User Interface

The forward facing program that a person will use to interact with software.  Many Hosted Private Branch Exchanges (Hosted PBX) or Voice Over IP (VoIP) Providers provide a GUI that makes it easier for a person to interact with their system.


IEEE – Institute of Electrical and Electronics Engineers

An association who’s prime goal is to advance technologies of all types.  This group is responsible for implementing the standards that all pieces of technologies use in order to communicate with each other properly.

IP – Internet Protocol

A standard set by the Institute of Electrical and Electronics Engineers (IEEE) for the transmission of data packets across networks.  It is an addressing and routing system that allows systems of all different types to communicate with each other, regardless of the manufacturer.

ISDN – Integrated Services Digital Network

Defined in 1988, ISDN is a set of communication standards that allows for the transmission of voice, video and data services over the Public Switched Telephone Network (PSTN).

ISP – Internet Service Provider

Any company, business or organization that provides access to the internet itself or services provided through the internet.  Familiar ISPs include Verizon, ATT, CenturyLink and Time Warner (to name a few).

IVR – Interactive Voice Response

IVR is also known as an Auto Attendant.  This technology is the voice you hear when you contact a business that asks you to select from a number of options by either speaking the option or pressing a corresponding number on the keypad.


LAN – Local Area Network

All of the devices that are connected to each other, within a certain area, is considered a LAN.  For example, in your office, your computers, printers, servers, routers and switches are all connected together and on a single LAN.

LD or LDC – Long Distance Calling

Any phone call that is made to an area outside of your locally defined area – sometimes, but not always, determined by a differing area code.  This type of calling is usually associated with higher or additional charges per minute.

LEC – Local Exchange Carrier

Another name for the LEC is the local telephone company.


MAC Address – Media Access Control

A MAC Address is an identifier that is unique to every physical device on a network.  MAC Addresses are typically assigned by the manufacturers and are not easily changed – unlike an Internet Protocol Address.

MPLS – Multiprotocol Label Switching

MPLS is a slightly different way of transmitting data between networks by adding labels to each of the packets.  These labels lay out the exact and direct path that the packet will take to get to its endpoint.


P2P –Point to Point

A type of connection, either virtual or physical, that directly connects two devices (locations).

PBX – Private Branch Exchange

A device, usually on Premise, that is the “Brains” of your business telephone system.  This piece of hardware serves as the local exchange for all of your inbound and outbound phone calls.  It also houses all of the features of your service, like your Interactive Voice Response, Voice Mail, etc.

POTS – Plain Old Telephone Service

POTS usually designates the older analog voice services, typically associating a single phone number with a single physical phone line and dial tone. This is as basic of a phone service as you can purchase.

PRI – Primary Rate Interface

The PRI is a voice and data transmission service level, typically used by medium to large businesses – in conjunction with a private branch exchange (PBX) System.  Each PRI Circuit allows for 23 simultaneous calls.

PSTN – Public Switched Telephone Network

The PSTN is the telephone cloud that we are all familiar with.  It’s the large interconnection of carrier networks that allow people to make phone calls to each other from anywhere in the entire world.


QoS – Quality of Service

The level of service and performance that a network sees, usually provided in terms of “uptime”.  When your business requires certain control of data and voice transmission, you should look for a provider that can guarantee QoS on the service.


SIP – Session Initiation Protocol

SIP is a protocol that controls the transmission and communication of voice and video over Internet Protocol (IP). It is the basis for being able to use Voice Over IP (VoIP).


VoIP – Voice Over Internet Protocol

In its basic sense, stands for any transmission of voice communications over an Internet Protocol (IP) network.  VoIP providers allow people to place phone calls using their existing data connections that are then routed through to the Public Switched Telephone Network (PSTN).

VPN – Virtual Private Network

Using encryption methods, two locations can setup a virtual connection between them across the public internet that acts as if they were directly connected to each other.


Did we miss an important one you’ve come across a lot? Leave a comment and let us know!