Powerline adapter & OWT DHCP

Hi all,
There's discussion about VLAN and the dhcp between OpenWrt and powerline adapters here How does PC get DHCP Address from VLAN over Powerline

But it is not very clear for me if I have OpenWrt router -> powerline adapter -> LINE -> powerline adapter -> end device.
I want the end device to receive IP address from the OpenWrt router DHCP server.

Now in the powerline adapters there's "obtain IP automatically" for the LAN. Which means it has DHCP client itself. The big question is does it have DHCP server as well ? Seems like TP link powerline device have SmartDHCP, which I don't know if it is troublesome for me. That's why I targeted Mercusys instead.
Hopefully the OpenWrt DHCP will directly work for the end device.

I'm planning to buy mercusys MP510 or MP500. MP510 has WiFi and also don't know if these create their own subnet, which is what I want to avoid.
My OWT router has ip/mac binding, so this is the main reason.


The MP500 looks similar to the TP-Link units I have. The only configuration possible is pressing a button to pair the adapter to other(s) in your network. The unit does not hold an IP address or even a MAC address. They work like an unmanaged layer 2 switch by sending any Ethernet packet through unchanged. They also pass VLAN tags through unchanged. I think this behavior is defined by the HomePlug standard.

An adapter with built in AP would work like the AP is attached to another port of the layer 2 switching network. Ethernet-to-Ethernet does not interact with the AP.

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I think you're right but on this "The unit does not hold an IP address or even a MAC address" there's a little argument. They do have mac address and IP address. In fact from the admin interface the devices can be paired by specifying the mac address of the device you'd like to pair with. There's "LAN" tab where you can obtain the address automatically or specify manually. This admin interface is actually accessed by the LAN IP address.

It works fine. It is virtually transparent. Device is able to get both IPv4 and IPv6. Adapters get their IPs from OpenWrt.

But beware, Poweline adaptesr usually perform bad under high load and introduce good amount of delay and jitter.

But do they create subnet and have own dhcp server ?

Side-note, powerline/PLC adapter can cause issues on DSL, especially faster VDSL2 links (e.g. using profile 35b) for your self but also for your neighbors, if neither of you uses DSL just ignore this :wink:

No, they should act as an ethernet wire, nothing else.

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No, they don't create anything.

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Thank you all ! I will buy then and will report back the quality. Some tp link adapters have OWT possibility. Which in turn has dhcp server option that is why I was confused.

Oh oh you can read https://community.tp-link.com/us/home/forum/topic/106148?sortDir=ASC&page=5

There is DHCP server in tp link adapters reported many times as issue.

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As I wrote before, "they should act as an ethernet wire, nothing else"... but bugs are bugs.

Some of them are extremely noisy. I used PLC to connect TV in the attic and could hear humming noise in my laptop (via headphones) during packets transfer. Not loud but extremely annoying.

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