Dedicated line

What is a dedicated line?
The term dedicated line can be traced back to the origins of the telephone call. In its simplest terms it means a permanent connection between two participants. In the early days, this really meant an actual phone cable between two callers.

The opposite to a dedicated line is a dial-up line. A dial-up line is, by definition, temporary. That means it is set up for the duration of the call and is therefore not permanently available.

Nowadays, dedicated line is used to describe any private network connection. With modern networks, cables may be shared, but dedicated lines can still be created to provide secure, permanently available connections between locations or users. 

Dedicated lines are also sometimes referred to as leased lines, private circuits or data lines. Dedicated lines are often considered more secure as they are not connected to the public internet.


What are the most common use cases for dedicated lines?

Dedicated lines are useful for a number of use cases. These include:

Home networking applications
Dedicated lines in home networks may include a PC or laptop connected directly to a data storage device with a high speed cable. In this scenario, data transfer between the two devices takes place offline, which makes it very secure and reliable.

Another example of a dedicated line in a home network application would be a thunderbolt cable which is used to transfer files between two Apple Macbooks. Again, the data transfer happens offline, making it totally secure. 

Corporate branch networks 
Dedicated lines can be used in a local area network (LAN) to connect two branches of the same company. The use of a dedicated line can help to maximise security for data transfers between the branches.

In the same way, companies can use dedicated lines to connect specialist facilities, such as manufacturing sites, to their headquarters or other administrative sites, for example. 

University networks
Many universities use dedicated lines to connect multiple buildings on campus, for example. Additionally, universities often operate a private internal network based on dedicated lines, giving students and faculty members access to secure services. 

Data centre and cloud connectivity
Many organisations, including financial institutions, use multiple dedicated lines from different service providers to connect their internal systems with remote sites, such as data centres. This increases security by ensuring that sensitive data never touches the public internet. Additionally, it means that critical data and services remain available even if one dedicated line goes down.

Does Voice-over-IP (VoIP) use dedicated lines?

[Translate to UK:]Yes, VoIP creates dedicated lines temporarily using SIP trunking functionality. This sets up a secure connection between users on the internet so that packets of voice data can be delivered and a voice conversation can take place. 

To find out more about dedicated lines and secure VoIP connections, please consult the following articles from NFON: 


Further information


A telephone connection is a standard part of telecommunications. In the following, we will first take a closer look at the term.

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