The Demarcation Point Explained


Have you ever heard of a demarcation point? It’s a term that can come up in telecommunications, but what does it mean exactly? Let’s take a look at  what makes the demarcation point unique and how it separates service provider territories from one another so that the customer is never left without service. Take a quick dive to learn more about this essential definition for a part of telecommunications services that is an important part of all businesses.

What is a Demarcation Point

A demarcation point is a physical line or boundary that separates two different networks. A demarcation point can be either a hardware device or a software application. In the case of structured cabling, hardware demarcation points are typically used to connect two different types of networks, such as an ethernet network for commercial premises. Software demarcation points are used to separate different logical networks, such as a guest Wi-Fi network from the corporate network.

The Types of Demarcation Points

There are different types of demarcs that can be found within commercial spaces. Each one pertaining to a different aspect of the business network while being a key component in the deliverability of services and protection that it provides. For the sake of structured cabling we are concerned with. Network interface devices (NIDs). A Network Interface Device is a physical junction housed in a weatherproof enclosure used for the interconnection of service provider cabling to connect it to the customer’s own equipment. 

History of the Demarcation Point

Prior to the early 1990s, the term “demarcation point” was not widely used in the telecommunications industry. It was in the early 1990s that the term started to gain popularity within the industry. The first known use of the term “demarcation point” is in a 1991 AT&T document titled “Network Interface Device Data Book”. The document defines a demarcation point as “the point of interface between the customer premises equipment and the network.”

The term “demarcation point” became more widely used in the mid-1990s as broadband Internet access became more prevalent. At this time, most demarcation points were located inside of homes and small businesses. The most common type of demarcation point was an ethernet jack that was connected to a cable modem or DSL router.

Today, the term “demarcation point” is still used in the telecommunications industry but its meaning has changed slightly over time. Generally speaking, a demarcation point is now defined as any physical or logical boundary between two networks. This includes boundaries between customer premises equipment (CPE) and network provider equipment, as well as boundaries between different types of networks (e.g., LANs and WANs).

Standard Practices for Demarcation Points in the United States

There are several standard components for demarcation points in the United States. The most common is the use of a punch down block. This type of device is used to terminate wiring on a variety of different types of jacks and outlets. Another common component of a demarcation point is the splice box. This type of device is used to join two or more cables together.