EFM stands for Ethernet in the First Mile. EFM refers to a type of circuit that uses multiple copper pairs to provide affordable but reliable, high speed IP connections for business sites. EFM can connect to the internet or to an IP VPN (or Ethernet) wide area network (WAN).
Most people are familiar with ADSL broadband, which offers an IP connection over a single 'phone line. An EFM circuit uses between 2 and 8 lines, which helps it deliver several major improvements over ADSL. Actually, its lines are referred to as Copper Pairs; they're the same wires that are used for phone lines, but in EFM they're not used for calls.
EFM offers several improvements over ADSL:
For performance and reliability, fibre is always preferable to copper.
Traditionally, businesses had the choice between a standard ADSL service and fibre-based Ethernet services. However, for some business sites, ADSL is not fast or reliable enough for their needs, whereas fibre-based Ethernet services are too expensive for them.
Happily, EFM sits right in-between ADSL and fibre Ethernet. It is relatively cost effective, but offers good reliability and performance and a speedy installation.
A very common application for EFM is for Business grade Internet Access, often called Dedicated Internet Access, or DIA. For example, you can have dedicated internet access using our FluidOne internet services.
It's important to ensure when you're looking at installing EFM circuits that will carry real-time applications such as SAP, Citrix and IP Telephony, that the circuit is delivered over a minimum of two pairs and with class of service (CoS). This will give better performance and resilience.
A common practice for some telco providers has been to reduce costs by offering lower speed EFM circuits on a single pair, and not providing CoS as an available option.
When ordering circuits for sites that will use real-time applications, always ensure that:
It will make all the difference!
Copper EFM circuits usually have quicker installation times than fibre circuits. So, if you've left it a bit late to order then a copper EFM circuit may just save your bacon as it only takes 30-45 days, rather than 90-180 days for fibre...!
Just like ADSL, factors like your distance from the exchange will affect the speed you achieve. That said, it ranges from 1-10Mbit/s for an EFM 2 Pair service and 10-20Mbit/s for an EFM 4 Pair service. Some telco's offer more pairs, which gives a faster service further away from the exchange.
There are several things you should look out for with EFM. A good managed network provider or network management service will cover all these things...so make sure you check that they do!