CISCO TDR Test - PAIR mappings

[stedaleo]

Thank you to all who have posted and responded to all of the TDR questions over the past which i have reviewed.

I could not find thru many searches any mention of what Cisco PAIR A,B, &  map to...

I would like to know if anyone can confirm the CISCO TDR output Pair A - Pair D mappings to the actual pins of the RJ45. I ask as i do not like assuming that PAIR A is PAIR 1 white/blue & blue/white  pins 4&5 of the connector.

I am hoping there is a table somewhere tahe looks something like this

PAIR A - pins 4/5

PAIR B - pins 1/2

PAIR C - pins 3/6

PAIR D - pins 7/8

will help identify which cable pair is bad in output

Thanks all

[Martin L]

I think it is
PAIR A - pins 1/2
PAIR B - pins 3/6
but let me check .. ....

https://learningnetwork.cisco.com/message/724426#724426

[balaji.bandi]

Look page 48-50 will have more information :

https://www.ciscolive.com/c/dam/r/ciscolive/us/docs/2017/pdf/LTRNMS-3602.pdf

[stedaleo]

Thank you for quick response.

I see the pin assignment for the 568A
As well as the pair a thru d

I did not see that Pair A from the output of the show cable output corresponds to specific pins.

I was hoping to see documented by Cisco that Pair A goes to RJ45 pins 4&5

Thank you again

[Martin L]

this is what I see on that pdf shared above

[Martin L]

and difference between standard A and B is https://www.flukenetworks.com/knowledge-base/application-or-standards-articles-copper/differences-between-wiring-codes-t568a-vs

[Martin L]

My cable tests show Pair A and B are good for cables with IP Cameras via PoE 3750/3850 running at 100 Mbps.  That's why I think pins are

PAIR A - pins 1/2
PAIR B - pins 3/6

source

https://www.cisco.com/c/en/us/td/docs/video/cds/cde/installation/guide/CDE_Install_Book/Connectors.pdf

shows 100Mb and 1000Mb Ethernet pairs.

will add some actual cable tests later

Regards, ML
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[Martin L · Accepted solution]

Here are test results from working cameras
sh cabl tdr int Gi4/0/39
TDR test last run on: August 26 09:43:27
Interface Speed Local pair Pair length Remote pair Pair status
--------- ----- ---------- ------------------ ----------- --------------------
Gi4/0/39 100M
Pair A 0 +/- 1 meters Pair B Normal
Pair B 0 +/- 1 meters Pair A Normal
Pair C 86 +/- 1 meters N/A Short
Pair D 86 +/- 1 meters N/A Short

Gi3/0/43 100M
Pair A 0 +/- 1 meters Pair B Normal
Pair B 0 +/- 1 meters Pair A Normal
Pair C 44 +/- 1 meters N/A Short
Pair D 44 +/- 1 meters N/A Short

This plus my picture above post will have to give us PAIR A - pins 1/2
PAIR B - pins 3/6, right?