Internet / WAN Circuit Handoff Guide: Demarc, MPOE, MDF, and more!

In this guide we'll define jargon and talk through considerations around internet or WAN circuit handoffs, one of the more complex parts of circuit installs.

fiber internet wan circuit handoff
Matt Pinto

May 25, 2023


The world of dedicated internet and WAN circuits is painfully frustrating, and this goes well beyond quoting and contracting. The dedicated internet access implementation process is rarely straightforward. One frustrating flashpoint we’ve seen, time and again, is conflicting expectations around carrier fiber circuit handoffs – the place where their circuit becomes your circuit.

To the uninitiated, a technical conversation about circuit handoff can feel like you’re swimming in alphabet soup, so we’ve compiled a handy glossary to get you up to speed.

  • Demarc (demarcation point) is the official end point of your service provider’s responsibilities. Any equipment or cabling after the demarc is no longer their problem.

  • MPOE (Minimum Point of Entry) refers to the physical entry point where the telecommunications cabling enters the customer property. In most cases, the MPOE will be installed directly into the building’s main telephone room.

  • MDF (Main Distribution Frame) is often used interchangeably with MPOE in instances where both points are in the main telephone room. Connectivity is distributed from here to all points of the building.

  • Extended Demarc is a network design feature used when the customer’s telecoms equipment is located somewhere other than the main telephone room. This occurs most frequently in multi-tenant buildings, where each tenant is obliged to make their own connectivity arrangements and contracts.

  • An IDF, or Intermediate Distribution Frame, is used in situations where the network distribution needs can’t be met by a single MDF. In plain terms, this would usually involve an MDF on the ground floor, where the MPOE is (i.e., where the cable enters the building). The rooms directly above the MDF would house as many IDFs, or additional telephone rooms as necessary. So, one MDF, with supplementary IDFs extending distribution across the property.

  • An SFP (small form-factor pluggable) is an interface that connects networking equipment (such as a switch, router, or network card) to fiber or copper cabling. They’re tiny, hot-pluggable (so, no need to shut things down when installing), use minimal power, and play nicely with pretty much any fiber or copper network cabling.

  • Patch cable/cord/lead these electrical or optical cables are used to connect or “patch” one device to another for signal routing. These can connect different types of devices, too, e.g., a switch to a computer or a router.

  • SC Fiber-Optic Connector. This square (or subscriber) connector can usually be found hanging off the end of your patch cord, and is designed to…you guessed it, connect to fiber-optic cables.

  • LC Fiber-Optic Connector. The SC’s smaller, younger brother, LC connectors are rapidly gaining popularity. Their slimmer profile makes them physically easier to use in more densely populated racks and panels.

  • The RJ-45 will be familiar to anyone who was plugging in a computer before 2008 – it’s the good old ethernet data connector.

Physical Handoff Types

To make sure you have the right equipment at your end for the handoff, it’s essential to know what kind of circuit you’re connecting. The three most common physical handoff types are electrical, single-mode fiber, or multi-mode fiber. Your choice of handoff type is often dictated by your throughput requirements, as well as the physical distances involved in your network layout.

We should mention that the numbers we’re throwing around here are in keeping with the “standard-issue” expectations. Should you choose to splash out for specialized transceivers, you can expect significant improvements in your performance metrics.


  • Speed – options include 10, 100, or 1,000 Mbps (not all carriers can provide 1,000 Mbps).

  • Cabling – electrical handoffs are provided from CAT5 or CAT6 copper cabling, connected with RJ-45.

  • Distance – signal loss becomes noticeable after approximately 328 feet (100m).

Multi-mode Fiber (MMF)

  • Speed – options include 1, 10, 40, or 100 Gbps (maximum speeds dependent on the fiber core size and the SFP used).

  • Cabling – the different MMF cable types (OM1 to OM5) offer different levels of performance based on their core size and other characteristics. They’re connected using either LC or SC connectors.

  • Distance – With throughput of 1 to 10 Gbps, optimal performance can be expected over distances of 1,800 feet (100m). For higher rates of throughput (40 Gbps or above), distance is reduced to 500 feet (150m) or less.

Single-mode Fiber (SMF)

  • Speed – 1 or 10 Gbps are the most procured speeds, though others are available.

  • Cabling – Usually a 9/125 cable, with a 1550 or 1310 nm wavelength. Again, LC or SC connectors are used.

  • Distance – single-mode fiber fares are much better than multimode over distance – in MMF, multiple light sources are operating simultaneously, which gets messier the further it goes, increasing attenuation. 

For 1 Gbps throughput with 1310 nm, SMF’s optimal distance is 3.1 miles (5km) or less. For 10 Gbps with 1310 nm, the distance is increased to 6.2 miles (10 km).

Other Information You’ll Need for Handoff

To make sure your install is as smooth as possible, make sure all parties are up to speed with the following.

  • The address for the location

  • The demarc location at the property

  • The business hours or site access hours

  • Contact details for both onsite queries and technical support

  • The type of power available at the location.

If you need a partner who eats telecoms jargon for breakfast, Lightyears automated procurement platform and team of experienced industry professionals are here to make your internet circuit installation as pain-free as possible. Get in touch today.

Want to learn more about how Lightyear can help you?

Let us show you the product and discuss specifics on how it might be helpful.

Not ready to buy?

Stay up to date on our product, straight to your inbox every month.

Featured Articles