Now as mentioned VPN or virtual private networks have replaced a lot of deployments of leased lines
but you'll still find them.
They've been around for a very long time.
And depending where you on the world this may be the only way to get a high speed connection to a business
site.
Now because these have been around a long time and have been used in various parts of the world they
often referred to with different terms or different names.
So the first term is a leased line which once again implies that you are leasing the line from a provider
you don't own the connection you are paying a monthly fee.
In other words a monthly leasing fee to lease the line from the service provider which would typically
be a telephone company or telco such as AT&T or British Telecom.
So some terms that you may come across include leased circuit or leased line.
These terms are often used interchangeably.
A circuit refers to the actual electrical circuit between the two endpoints in the old days we used
to have circuit switch networks where you'd make a telephone call between two sites and use an analog
modem to send traffic between those two sites.
So it was a circuit that was established for the duration of your telephone call a leased line however
is a dedicated circuit between two sites so you don't have to make a call to send data across it.
It's a permanent point to point connection between the two sites.
You may also come across the term serial link or serial line.
Once again these are used interchangeably and mean the same thing.
The term serial in this case refers to the fact that the bits sent across the wire flow serially and
that Rod is used serial interfaces to make the connection a point to point link or point to point at
least.
Line refers to the fact that you are making the connection between two points rather than between multiple
sites at the same time.