use an ADSL modem/router as a Bridge and Switch at the same time.

[Oceans12]

Hi everyone,

this is seems wild but I decided to give it a shot by asking this anyway.

I have 1 ADSL Modem+Router (with WIFI) = Lets call this A
and
1 LAN Router (no WIFI) = Lets call this B

what I want is the following:

Internet > A > B

(remember B is necessary here)

But Since B does not have wifi. I cant use it wirelessly. I have ordered another WIFI Router C for this purpose.

then I will simply do

Internet > A > B > C

but while C arrives, I am impatient.😀

Now i know for a fact that ADSL routers can be used as a switch, All you have to do is put internet input LAN wire on a LAN PORT, and turn off DHCP on it.

my weird question:

Can i make it such a way that I make A into bridge mode, do my PPPOE authentication in B . then using another LAN wire as output from B put it back into A on LAN PORT. and use it as a switch for B (because A has WIFI).
and use it ....

in other words . use A as a bridge mode for internet and use its wifi as a switch at the same time 😀?

please note that i am a networking layman ( just can do simple things)

thank you for your time

 

[bill001g]

The switch part might work but it is highly likely the wireless will not. Most modem/routers disable the wireless part when you put them in bridge mode. I suspect they would disable the switch part if they could but since that is a hardware chip it would need a special feature to not allow traffic between the ports.

I suppose it would not hurt much to try it. This is like overlapping 2 subnets it works but can causes issues.

Maybe simpler to just use the router part of the adsl device until you get your other router.

 

[bill001g]

There is no way to predict if this can work. When the device is in router mode even if the ADSL is disconnected there is software running that moves traffic between the radio chips and the switch chip that runs the lan ports. When you set it to bridge mode it all depends on the device. Most I have see actually turn the radio chips off in the device. Now maybe you can turn them back on and maybe the software to bridge between the wireless radio and the lan switch is running. This is not a common or recommended configuration so its hard to say what the router manufacture does.

 

[Oceans12]

The switch part might work but it is highly likely the wireless will not. Most modem/routers disable the wireless part when you put them in bridge mode. I suspect they would disable the switch part if they could but since that is a hardware chip it would need a special feature to not allow traffic between the ports.

I suppose it would not hurt much to try it. This is like overlapping 2 subnets it works but can causes issues.

Maybe simpler to just use the router part of the adsl device until you get your other router.

are you sure about wifi disable at bridge mode . i have never heard of that. and although i did not try it yet.

when i select bridge mode in my adsl modem . the wifi option is on and active (i just dont save it because i really cant use it with wire for now).

all my setup is on a wall on separate corner so it will take a while to even try a temporary setup.

im just wondering if all this is worth the effort

 

[nigelivey]

Worth the effort? I expect not.

 

[Sylvvester]

You are making it overly complicated. You can't do PPPoE authentication on B since it's not adsl router.
What you should do is PPPoE authenticate on A and configure B to make different network than A (example: A network 192.168.0.0, B network 192.168.1.0) and then connect LAN port on A with WAN port on B.