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While I too love to see good cable layout, whenever you see a “thousand” Ethernet cables in one run, a foundational mistake has been made. Instead of 1000x 1 G

While I too love to see good cable layout, whenever you see a “thousand” Ethernet cables in one run, a foundational mistake has been made. Instead of 1000x 1 Gbps links, the proper way is to consolidate those into 10x 100 Gbps links or whatever works out to be the cheapest given the length of the run, the cost of the switch ports, etc… Any argument to the contrary has a solution. E.g.: even multi-tenant links with overlapping address spaces can be handled with nested VLANs (VXLANs). This is essentially how cloud providers and large metro network provides handle multiple customers. The last time I saw cabling like this was at a government department with “network techs” that didn’t get these basic concepts. Instead of having “top of rack switches”, they had one giant pair of switches in the corner of the data centre with bundles of cables coming out the thickness of my torso! The same department had a long building with switches in one corner and bundles of cables in the ceiling going to desktops over 100m away. In all cases this was done neatly. They loved cable porn, but didn’t understand networking!

teepo 4y ago
I like the old Softlayer / IBM Cloud cabling scheme: dual 10Gbps to TOR (red)and BOR (blue) and the 1Gbps green cabling into the IPMI. Here's a pic: https://newsroom.ibm.com/IBM-cloud?item=32774 https://newsroom.ibm.com/IBM-cloud?item=32774
oasisbob 4y ago
> While I too love to see good cable layout, whenever you see a “thousand” Ethernet cables in one run, a foundational mistake has been made. How about in large campus environments with extensive copper plants? Bundles arriving into an IDF for Ethernet/POTS serving several hundreds of pairs of eyeballs get big fast. Trunking doesn't save you here.
- kazen44 4y ago
  Another example. Residential fiber networks can get messy very quickly, especially if its all based on AON instead of GPON, and requires a point to point connection between a customer's edge location and a site end location. Add in (older) coaxial networks in to the mix aswell, and you end up with thousands of bundles of fiber for even small towns. Also, keeping all that organised requires rigerious discipline and maintenance to keep it all tidy and neat.
  - oasisbob 4y ago
    That's a good one. One of my favorite cautionary stories is of the telco which, for cost-savings reasons, deferred drops and cleanup across their entire plant. As the story goes, digging out of it was horrible, expensive, and epic. Not hard to imagine why.
mdip 4y ago
You are correct and I should have clarified a few points. Especially given the time (my memory is hazy but I want to say this would have been just before Y2K) -- almost all of the business and management network was ... token-ring[0]. I don't think these cables were even for that network (we usually ran those and they didn't come with much in the way of "rules"), but were for the SONNET/voice network (memory, again). [0] When I came on in ~1998 most of the (PS/2) machines were connected via token ring. A lot of the work I was doing at the time involved replacing PCs with newer models and getting them plugged into one of the managed 100MBps switches. :)

teepo 4y ago

I like the old Softlayer / IBM Cloud cabling scheme: dual 10Gbps to TOR (red)and BOR (blue) and the 1Gbps green cabling into the IPMI. Here's a pic: https://newsroom.ibm.com/IBM-cloud?item=32774 https://newsroom.ibm.com/IBM-cloud?item=32774

oasisbob 4y ago

> While I too love to see good cable layout, whenever you see a “thousand” Ethernet cables in one run, a foundational mistake has been made. How about in large campus environments with extensive copper plants? Bundles arriving into an IDF for Ethernet/POTS serving several hundreds of pairs of eyeballs get big fast. Trunking doesn't save you here.

kazen44 4y ago
Another example. Residential fiber networks can get messy very quickly, especially if its all based on AON instead of GPON, and requires a point to point connection between a customer's edge location and a site end location. Add in (older) coaxial networks in to the mix aswell, and you end up with thousands of bundles of fiber for even small towns. Also, keeping all that organised requires rigerious discipline and maintenance to keep it all tidy and neat.
- oasisbob 4y ago
  That's a good one. One of my favorite cautionary stories is of the telco which, for cost-savings reasons, deferred drops and cleanup across their entire plant. As the story goes, digging out of it was horrible, expensive, and epic. Not hard to imagine why.

mdip 4y ago

You are correct and I should have clarified a few points. Especially given the time (my memory is hazy but I want to say this would have been just before Y2K) -- almost all of the business and management network was ... token-ring[0]. I don't think these cables were even for that network (we usually ran those and they didn't come with much in the way of "rules"), but were for the SONNET/voice network (memory, again). [0] When I came on in ~1998 most of the (PS/2) machines were connected via token ring. A lot of the work I was doing at the time involved replacing PCs with newer models and getting them plugged into one of the managed 100MBps switches. :)