Re: TP Transceiver

jinkazama_2 · ‎11-02-2004

Hi Guys,

This may seem like a stupid question, but what are the TP Transciever (that i receive with all my Routers) used for? I assume they are used for Connecting to the AUI Ethernet Ports on my Routers for uplinking... allowing me to use RJ45?

IF so , what are the different switches on it for? I cannot find any literagture on it. Any description or links would be much appreciated!

Thanks

Omid

peter.mainwaring · ‎11-03-2004

I assume you mean the transceivers that convert from an AUI connection to an RJ45 connection. The transceiver is a "transmitter/receiver", which (as the name suggests) transmits and receives Ethernet frames to and from the network.

Where devices have an onboard RJ45 Ethernet port, the transceiver is internal. If you use the old type D-connector AUI port, it requires an external transceiver which can be attached to a 10-Base-5 coax cable (the old type Ethernet) or plugged directly into the back of the AUI port to convert to a different type of wiring system (in your case RJ45).

You are correct in your assumption that you use the AUI port for uplinking.

The switch on it will be the SQE enable switch. Make sure this is in the OFF position otherwise the router will think that there are excessive collisions on your network. It is especially bad if a switch or hub is attached to a transceiver with SQE enabled. SQE isn't used any more, but for an explanation, see http://www.cisco.com/en/US/tech/tk389/tk214/technologies_tech_note09186a00801d8335.shtml

Hope this helps.

Pete

jinkazama_2 · ‎11-03-2004

Thanks for the help mate! This shows how gettign hands on experience is invaluable... i got my CCNA and i dont even know basics like this! :)

Thanks buddy!

andrew.butterworth · ‎11-05-2004

I disagree about SQE being enabled when connected to a Router. It should be ENABLED when connected to an end device such as a PC, a Router, a Bridge etc, but DISABLED when connected to a hub/repeater:

http://www.ethermanage.com/ethernet/sqe/sqe.html

Good luck

Andy

peter.mainwaring · ‎11-08-2004

Yes - you are right about routers. Its hubs and repeaters where it causes problems.

However, I fairly sure that virtually all other devices (PC,s, routers etc.) these days don't use SQE as a mechanism to determine that frames have successfully been transmitted to the network, so I don't think it would matter if SQE was off or on for those devices.

Pete

andrew.butterworth · ‎11-09-2004

Pete, you are probably correct regarding SQE being irrelevant on PC and routers these days. When was the last time you came across a NIC with an AUI connector??? I am sure if it has an AUI it will have the SQE circuitry - I know my old 2500's have :o)

Andy

peter.mainwaring · ‎11-10-2004

Good point!

Pete