How to Connect a Landline Phone to a Modem?

Most people don’t differentiate between regular digital landline phones and VoIP (Voice over Internet Protocol) phones. That’s why we end up answering questions such as “How to connect a landline phone to a modem?”

In our efforts to simplify and further explain the topic, we’ve decided to discuss what landline phone technology is, what VoIP technology is, and how to connect a phone to a modem. Hopefully, this article helps you with your inquiry.

Landline Phone Technology

The POTS (Plain old telephone service) transmits voice using analog signals and copper wiring. We get to speak to other people using these wires and analog signals. Now, it’s a bit more complex than that.

The telephone line is a twisted pair of copper wires, the pairs are comprising 4 different cables. Usually, there’s a brown, orange, green, and blue one. These cables go from an exchange circuit board to our home.

We have a numeric keyboard that has a circuit board below, and we can push the buttons to engage in digital dialing. All the digits have a DTMF (Dual-tone multi-frequency signaling), and the DTMF reaches the exchange, which uses a computerized system to locate the recipient and connects us.

So, this is how calling a friend works. We lift the handset and put it to our ear. That’s when we hear a dial tone, so we push the numbers to call our friend. The dial tone is the signal that we have an open connection to the exchange circuit.

We’re sending signals to the exchange by pushing the buttons, and then the exchange sends signals to our friend, so the phone starts ringing. Once they pick up the phone, there’s a circuit between our two phones, and we talk until one closes the circuit (hangs up).

VoIP Technology

VoIP Technology

VoIP (Voice over Internet Protocol) transmits voice over the internet using IP (Internet Protocol). That’s why you usually come across terms like broadband telephony, IP telephony, or internet telephony.

This type of phone system takes our voice signals and converts them to digital signals so they can be sent through our internet connection. There’s a VoIP server that connects our calls to our recipient’s phones.

VoIP and other services

Even though newer landlines in the world probably work through VoIP technology, there are still some that use the PSTN (Public Switched Telephone Network), and most people have a smartphone. So, how are all these channels communicating with each other?

When we make a call from a mobile phone to a landline number, it works the same way a phone call from one landline to another would work. By dialing the numbers on our phone, we enter the registers that are searched for the recipient.

After the recipient is found, the nearest base station contacts the phone in the recipient’s hand, and this makes the phone ring. This is usually done through the SS7 (Signaling System No. 7). So, there’s a way to connect a landline to a mobile phone.

VoIP to landline connections are a little different because the call placed from VoIP to a landline phone needs to use the landline network until it reaches the recipient, and that’s why sometimes you might get charged extra when using a VoIP phone.

But, if you don’t contact someone using a landline, and you try to make a call to someone also using a VoIP phone, your call is probably free as it is a part of your internet access subscription.

VoIP benefits

There are many benefits when speaking about VoIP phones. The first thing is that it works over the internet, and the other benefits include:

  • Cost-effectiveness: The calls we place using a VoIP service seem free, but we pay for them because we pay for our internet subscription. However, it’s probably much cheaper than using an old telephone line.
  • Less hardware: We get to have a lot with a little hardware, there’s no need for several ports, different systems for better functions, or just the basic functions that we have on our mobile phones.
  • Better functionality: VoIP phones have almost all the functions of our mobile phones, if not more. We can forward calls, we can transfer calls, block numbers, put calls on hold, etc. To do that with a regular landline, we’d need a ton of equipment that would take up a ton of space.

How to Connect a VoIP Phone to a Modem?

Now that you know the benefits of VoIP, and how these work, let’s discuss how we can connect a VoIP phone to a modem. We need to go through the VoIP phone part checklist, and a few simple steps to ensure that there’s a connection between the VoIP phone and the modem.

VoIP phone part checklist

Almost all VoIP phones look like regular landline phones, so they all have a base unit, a handset, a handset cable, an Ethernet cable, a stand, and a power cable. The Ethernet cable is the only difference between a regular landline phone and a VoIP phone.

The handset is the earpiece, and the handset cable differs from the Ethernet cable. They look quite similar, that’s why most handset cables are coiled, so we can tell the difference and properly install them.

VoIP phone modem connection

The first thing we need to do is assemble the phone. Take the handset and connect the handset to the handset port on the phone base unit using the coiled handset cable, then place the stand below the phone base.

Use an Ethernet cable to connect the phone to your modem using any of the ports on the modem. The port on the phone base unit needs to be SW (switch). Once you connect these, you can turn on your VoIP phone, i.e. plug it in.

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Now you know the differences between regular landline phones and VoIP phones, and you understand the benefits of VoIP phones. Also, you understand you don’t need to know how to connect a landline phone to a modem, but how to connect a VoIP phone.

Finally, if you’re having trouble installing your VoIP phone, contact your VoIP service provider to ask for help or more detailed instructions.

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