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While looking for different types of network cable, I came across this term called 25-core cable. You can get numerous examples putting the term '25-core cable' in any search-engine. But till date haven't found a single document which explains what this 25-core cable is or 16-core or 8-core ?

By a single core does it mean a single LAN cable which connect at both ends to a single RJ-45 connectors . If I'm assuming it right it would mean having 25 connectors at each end. This would be from taking bunch of cables from a say a 'network closet' to going doing to a basement or something which if I understand is called 'backhaul networks'.

Am I right in assuming then anything apart from a single core LAN cable is for backhaul networks or is there any other scenario where such multiple 'cores' cable is used.

Update :- meant a 25 'pair' cable and NOT 'core'. I did remember reading about it though.

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Are you sure you are talking about network cable? Where did you see this? What was the exact context? Are you sure you aren't talking about phone cabling? IE… – Zoredache Mar 18 '14 at 17:04
I don't know for sure, but it certainly seems like a simpler way to backhaul multiple cables across tight areas (instead of 3 RJ45, or 12 RJ11, etc). – NickW Mar 18 '14 at 17:04
I never heard "25 core" but definitely heard "25 pairs", "50 pairs", "100 pairs". Whatever, don't do it for network. It sucks. cross-talk is incredibly high. Seems "easier" to run 1 25 pair but damn it sucks. Then you have them all on a punch down block, all wires untwisted etc. Good for phone, not for network. – ETL Mar 18 '14 at 17:11
Yeah, I think it's a cable for the RJ21 connector.. like this : – NickW Mar 18 '14 at 17:11
ah, yes 25 pair and things like that. For e.g.… – shirish Mar 18 '14 at 17:27

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