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New Member

Creative port configuration.

Is there a way to configure a serial port (on a 2501) to talk to an ethernet port (on an 831) ?

Perhaps with INT ASYNCH and ENCAP PPP ?

Any thoughts appreciated.


Re: Creative port configuration.

Both serial and ethernet use totally different technologies, I m not sure what you are trying to achieve here.

New Member

Re: Creative port configuration.

Well, I'm trying to do something I'm not supposed to be able to do.

Now, I realize that voltages might be a problem but as near as I can tell the serial port only uses 8 pins anyway, so I'm thinking that with the help of a piece of intermediary hardware (perhaps similar to the transceiver for an AUI port), and some clever configuring of either or both ports, maybe I can get a serial port to talk to an ethernet port.

Re: Creative port configuration.

If your aim is to make both 831 and 2501 talk, then what you need to do is buy a transceiver (AUI to rj45 converter) for the 2501 ethernet port and make the port talk to the ethernet of 831 router, using either a hub/switch or cross over cable.

It costs 12 dollars at this website.


New Member

Re: Creative port configuration.

True, I can do that. In fact, I already ordered one yesterday.

But then I would end up plugging both my LAN switch and the 2501 into switch ports on the 831 in a "Y" configuration.

What I actually want to do is daisy-chain them:

Cloud>DSL Modem>831>2501>LAN Switch

FYI, this is for a home lab, not a production environment, so nobody is going to yell at me if I break anything.

Re: Creative port configuration.

For this topology, I would recommend using a cross over cable (ethernet 1,2,3,6 crossed) between 800 and 2500 router. That way you can save the switch for your hosts on the 2501 side.

New Member

Re: Creative port configuration.

I'm sorry...

Crossover cable between what?

Re: Creative port configuration.

Sorry abt the mistake....I see that you dont have a free ethernet port on the 2501, once you connect it to the switch. Now you are left with one ethernet port on the 831 and 2 serial ports on the 2500.

As a last resort, you can hook the aux ports of both routers back to back and configure them to communicate. The max speed supported would be 9600 bps.

New Member

Re: Creative port configuration.

Yeah, I wanted to avoid that.

Actually, another solution did occur to me while we were talking.

I could go from the AUI port on the 2501, through a transceiver, into a switch port on the 831, then hook two different computers into the two different serial ports on the 2501, using COM ports on the computers. That would at least get me ISDN-like speeds (115,200) and I would still have 3 ethernet ports left over on the 831's built in switch.

I suppose I could also hook the two serial ports to each other using a DTE/DCE cable and just put a clocking speed on one of the ports.

Finally, I suppose I could use sub-interfaces on the AUI port. (I think... have to check my books)

But of the different choices I suspect the one that is most interesting is making serial connections directly from the computers to the 2501.


and this might be the very best thing...

I could buy another 2501, which would let me hook the two 2501's together and play with multi-homing and load balancing, as well as leaving me an AUI on each "end"

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