Remember “The Matrix” where you had to use a landline to get in or out of the Matrix.

I know why they did it this way, just bear with me.

Escaping the Matrix
Figure 1. Escaping the Matrix

Rebels were transferring their consciousness back and forth when connecting themselves to the Matrix. Not sure how much is that in Kbits, depends on how conscious you are probably. In any case you need a stable communication channel for that.

Ideally the channel you are looking for should provide the following:

You also want this communication channel to be a physical link between two parties for guarantied stability.

The way out
Figure 2. The way out

Does any of this sound familiar?

Right, I’ve just described circuit switching that is used in traditional telephone networks. When you make a call, telephone switches create a physical wire circuit between two phones, which guaranties fixed bandwidth, delays and delivery order. They didn’t pick Internet with packet switching because they wanted to avoid long packet transfer delays, timeouts and packets reordering.

Packet switching
Figure 3. Packet switching

It seems also that a landline was considerably harder for agents to track and eavesdrop or interrupt. As you need a physical access either to the circuit being used or one of the phones.

In any case, I believe that it was a solid choice, you just need to be sure that no one is holding the line.