Mixing powerline adapters and the bandwidth consequences?

FleaBag

Hi guys, I was hoping someone with a little experience in the matter might be able to shed some light on a situation I have. I've tried searching for an answer but don't seem to be able to find this specific scenario.

I want to buy some TP Link Powerline adapters. I'm familiar with AV2 and understand how that works as far as I can tell. I'm going to buy a set of 1300Mb/s AV1300 adapters for connecting my XBOX, TV and Chromecast Ultra by ethernet and the router at the other end. That should all be fine. I want to then add a Powerline WiFi extender in a bedroom upstairs. The plan is to use a 600Mb/s TP Link device here as it's just going to connect a Chromecast, a phone and a laptop.

So my question is, would the entire Powerline network be limited to 600Mb/s? Or just the devices connected through the WiFi extender in the bedroom? My understanding from some research is that this would in fact be the case - if I want to ensure my other Powerline ethernet connected devices benefit from the 1300Mb/s bandwidth I would need to buy a higher capacity WiFi extender for the bedroom?

Thanks in advance.

mickevh

I haven't researched the HP technical details for a few years, but when I last did basically each HP links up to each other at the best link rate (ever erroneously called "speed") they can, which of course depends on the  capabilities of the devices, the noise on the mains, interference, etc. etc.  Wiki's article suggests AV2 is backwards compatible and interoperable with previous generations except HP 1.0. Thusly I'd be surprised if a 600mbps plug pulled all the rest down to the same rate, but you never know. I suggest you buy from somewhere with a good returns policy just in case.

The important thing to understand about HomePlug if you want to get into the numbers game, is that the "protocol efficiency" is low at about 45-55% and HP uses a "common bus" Half-Duplex operating paradigm.

Protocol efficiency indicates the percentage of the link rate "lost" due to error correction, encryption, management overheads and so on to "make it work" (by comparison Wi-Fi is typically about 55-75% and ethernet is about 95% efficient in round numbers.)

Common bus and Half -Duplex means that only one plug at a time can transmit across the mains at any given time - the more plugs you have, the more data they wish to transmit, the more "competition" there is to gain control of the medium and transmit (IIRC HomePlugs do it on a time slicing basis - the "master" plug mediates which plug gets the next transmit window, then the plug transmits to its target at the best rate it can which could be different for different plug pairing and different in each direction - though this is all happening dozens of times a second.)

The upshot is that one doesn't expect anything like the performance indicated by the link rate at the application level (file copying, speed tests, streaming, etc.)

FleaBag

Thank you for your very in depth and insightful response. This information is very useful and I will take your advice and buy from somewhere with a good returns policy. I will post my results here incase anyone else stumbles on this thread in future.

mickevh

Please do, plenty of us here would like to hear the outcome.

ChuckMountain

To add don't be surprised if you only get around a tenth of the advertised speed.  If you need a specific throughput and that is above that then I would plan for something else.  That would be either hardwired or a mesh WiFi