Solved

Perfect crosstalk?

Posted on 2013-01-03
3
322 Views
Last Modified: 2013-01-27
Weekend fun:

(I know it's not best practice, don't tell me... :) )
Setup: only one cat5 (solid core, around 50-60m run) copper to a classroom, need access for lecturer PC and wireless AP. Instead of small managed switch, I went with a passive splitter.
AP receives 24V POE on far end after splitter.
AP immediately falls back to and stays on 10meg connection, error counter on 0 after days, appears to be working perfectly, wireless clients happy.
Fun part: sometimes the MAC of the AP appears on the 'wifi vlan' port (good thing), and also on the 'student vlan' port where the split cable PC is.
Double-checked, vlans are not bridged together in the area.

So: what's your guess? Perfect, full-frame crosstalk on the splitted cable, or the otherwise perfectly reliable 3Com 4400 box started bleeding between vlans, or other?

Cheers,
Tamas
0
Comment
Question by:TimotiSt
  • 2
3 Comments
 
LVL 45

Assisted Solution

by:Craig Beck
Craig Beck earned 300 total points
Comment Utility
Crosstalk wouldn't make a MAC address appear on a different port.  This would only be caused by a bridge or loop.

Do any of your student clients have wired and wireless connections back to the same switch?  If so, make sure none of them have inadvertently bridged their NICs.

Also, make sure your STP is working properly.
0
 
LVL 17

Accepted Solution

by:
TimotiSt earned 0 total points
Comment Utility
Okay, got this one:
The Cat5 run in the wall is patched up somewhere, where it has strange cable shorts. Pins 1,2,3 and 6 are not shorted to each other, but they are to random other pins, so it's a mess...
Couldn't originally debug with my cheap cable tester...
Anyways, it kinda works with only one 100Meg connection, without a passive splitter. But I'll definitely need a new cable run...

Tamas
0
 
LVL 17

Author Closing Comment

by:TimotiSt
Comment Utility
Managed to debug the cable.
0

Featured Post

Highfive + Dolby Voice = No More Audio Complaints!

Poor audio quality is one of the top reasons people don’t use video conferencing. Get the crispest, clearest audio powered by Dolby Voice in every meeting. Highfive and Dolby Voice deliver the best video conferencing and audio experience for every meeting and every room.

Join & Write a Comment

This tutorial will go through the steps required to write a script that will back up the configuration settings of a HP-ProCurve switch. You will need to get the following things to follow this tutorial: Telnet Scripting Tool e.g. TST10.exe …
I eventually solved a perplexing problem setting up telnet for a new switch.  I installed a new Cisco WS-03560X-24P switch connected to an existing Cisco 4506 running a WS-X4013-10GE Sup II-Plus. After configuring vlans and trunking,  I could no…
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, Just open a new email message.  In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…
This tutorial demonstrates a quick way of adding group price to multiple Magento products.

763 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

5 Experts available now in Live!

Get 1:1 Help Now