Question Why does using two powerline adapters connected to the router bottleneck bandwidth?

[IzzyDz]

Hi,

I am in a student house with three others, and we all use TP-Link powerline adapters. We had one powerline adapter connected to the router, and a powerline adapter in each of our rooms. I made the assumption that splitting one powerline adapter into four would limit bandwidth, so I tried connecting a second powerline adapter to the router. Both powerline adapters connected to the router are of the same model, and the firmware of each powerline adapter on the network is updated. However, after doing this, the bandwidth has greatly decreased and looks like it's being bottlenecked.

Why does connecting two powerline adapters to the router cause the bandwidth to be lower than just using one? Apologies if the question is unclear, please let me know if any more clarification is needed.

Thanks!

 

[kanewolf]

Hi,

I am in a student house with three others, and we all use TP-Link powerline adapters. We had one powerline adapter connected to the router, and a powerline adapter in each of our rooms. I made the assumption that splitting one powerline adapter into four would limit bandwidth, so I tried connecting a second powerline adapter to the router. Both powerline adapters connected to the router are of the same model, and the firmware of each powerline adapter on the network is updated. However, after doing this, the bandwidth has greatly decreased and looks like it's being bottlenecked.

Why does connecting two powerline adapters to the router cause the bandwidth to be lower than just using one? Apologies if the question is unclear, please let me know if any more clarification is needed.

Thanks!

I am guessing that they are both generating noise (that is actually power line network works. The adapter generates high frequency signal that carries on the power line). Two of them plugged into the same outlets may cause them to interfere with each other.

 

[bill001g]

Kinda for the same reason your neighbors using wifi degrades your wifi performance.

Lets say you have 4 powerline units in one network. These since they communicate will attempt to share the total bandwidth...lets say 100mbps.
Since they know about each other they will attempt to not stomp on each other transmission.

Now instead you have 2 groups of powerline units with 2 units each. It is still 4 units total but in this case the 2 groups do not know the other exists. They use different encryption codes. They both will attempt to use the same 100mbps of bandwidth but they make no effort to coordinate their usage since they don't know about each other.

Unlike wifi you can't use other radio channels, all powerline unit attempt to use the same frequencies since there is really only 1 commonly used block of frequencies