What Is a Leased Line?

A leased line will typically be a private fibre cable ran from your business back to an exchange or network point of presence. This is commonly used to give you a dedicated and uncontended connection to the internet or provide you with a site to site connection. And because your connection is not shared with anyone else (like a standard broadband connection), your bandwidth will not be affected by usage during peak times. Businesses will typically rely on their fibre leased line for: Ultrafast connection to the internet, performing jitter free VoIP calls, connecting multiple servers and computers in different locations and allowing employees to connect to their computers remotely.

You can get a choice of ‘bearer’, this is the term used to describe the size / speed of your cable, the choices are 10Mbps (obsolete in many locations now), 100Mbps, 1000Mbps (1Gbps) or 100000Mbps (10Gbps). It is possible to have a 1Gbps ‘bearer’ and only take a 50Mbps service over it. Why would I not take a smaller and cheaper ‘bearer’ if I only need 50Mbps? The answer is simple, you may want to quickly upgrade in the future without any hardware or network changes. You would simply ask your provider to up the service speed and it’s simply a case of the provider turning the dial up. If for example you took a 50Mbps service on a 100Mbps bearer you would not quickly and easily be able to receive speeds of 200Mbps because your line speed is only 100Mbps. A leased line is uncontended and completely unmetered, it is solely for your use.

A leased line is used to deliver internet connectivity or to provide connectivity between sites, for example a Head Office and a Branch. These private circuits (also known as MPLS) between sites can be used for aggregating costs and services. You may have a VoIP phone system in the HQ, CCTV or some on premise application server that you want accessible at one or more branch sites. A leased line is dedicated to your business or organisation, the data rates are full duplex so you get the same upload capacity as you do download.

Leased lines will always be much more expensive than broadband type connections because they are dedicated to you, you will expect to pay hundreds of pounds a month rather than tens of pounds for broadband. You can also in some circumstances expect to pay excess construction charges, see our example below in the disadvantages of a leased line section.

A leased line is also known as an Ethernet circuit, this is because it will be traditionally delivered using Ethernet from your location (the A end) to the B end or in the case of a single internet connection it will be delivered using Ethernet technologies. This is a premium service and it comes with a guaranteed fix time or SLA (service level agreement) unlike broadband which is normally best endeavours. Leased lines are always dedicated to you only, no one is going to be sharing your speeds, this means no slowdowns when the network is busy, the guarantee is that you will get what you pay for at least 99.9% of the time. Leased lines are always symmetrical so you get the same amount of data upload as you do download, this is also another key differentiating factor when comparing with broadband, in broadband networks the service is weighted heavily in favour of the download speeds meaning that the upload speeds are often 80% or more LESS than the downloads.

As a premium type service, a Leased line can be expensive to have installed in the first instance and it can be often delayed due to factors outside of the provider’s control. Excess construction charges known as ECC’s are costs you are expected to bear to have the circuit installed in the first instance. These can range from £0 – £100’000, yes they really can be as large as one hundred thousand pounds or more. If for example miles and miles of new ducting or poles need installing and roads need closing off to facilitate the installation of this new infrastructure, you as the requesting client will have to pay for it, only for any future client ordering a service to benefit. You can imagine in this example none of this happens very quickly hence long lead times.

A VPN is often used to provide secure site to site connectivity rather than using a MPLS network over leased lines, the problem with using a VPN is that they can be used as a cost saving measure and in this deployment example the internet connection will be a broadband connection suffering from the slowdowns and problems associated with contention. VPN’s also have an increased latency overhead.

Broadband is cheap and very accessible and if you need an internet connection without any speed guarantees or guaranteed fix times then this is your best option. An internet leased line offers all of the certainty required for business clients and symmetrical speeds so perfect for a business who needs to upload lots of data.

The term dedicated leased line refers to a leased line that is used solely by one business to connect to the internet or another office. Most commonly, a dedicated leased line will be delivered through fibre optic cables or a microwave internet connection.

The terms: “dedicated line” and “leased line” are most commonly usually used interchangeably. So, it’s fair to assume that anyone talking about a dedicated line is actually talking about a leased line – be it a fibre leased line or a wireless leased line.

The only true alternative to a fibre leased line is a microwave internet connection. A solid microwave internet solution will give you all the benefits of a leased line, just without the upfront costs. It is commonly accepted that microwave internet is in fact better than a leased line for many businesses.