Hacker News Reader

Comment by no_carrier | Hacker News Reader

Network engineer of 20+ years here, but I'm struggling with this 'fished' terminology. Does it mean when a cable is pulled through on a piece of string?

View on HN

> Does it mean when a cable is pulled through on a piece of string?

That is often exactly what is meant. The problem of running Ethernet through existing structures has spawned a bunch of tools, including glow-in-the-dark "fish tape."

The process is often brutal, and looks like tug-of-war when it takes a couple men to pull the bundle through a couple 90 degree turns. As such, we have "plenum" cable, which is much tougher than typical patch cable, because the latter would just get shredded inside the structure, or snap when pulled with a few hundred lbs of force.

For really long runs in industrial settings they have battery powered pullers that use a really strong string.

> The problem of running Ethernet through existing structures has spawned a bunch of tools, including glow-in-the-dark "fish tape."

None of these tools are new (well, the glow fish sticks I think are a recent innovation) or unique to ethernet. Electrical wire is installed the same way, eg. in conduit. There's even a special lube for making your wire slide through the conduit easier.

I remember seeing glow rods 10-15 years ago in the cable industry.

> There's even a special lube for making your wire slide through the conduit easier.

A fellow engineer had to wire (Ethernet) an office, but he didn't have the silicon-based lubricant, so he bought vegetable lard at the corner shop... since there were conduits, it didn't really smell bad unless someone needed to replace a wire. It was surprising that no insect tried to eat the lard for the couple of years it lasted.

AFAIK plenum cable also needs a certain fire resistance rating. "Plenum" means something like a hidden space where air flows.

Yep! Might be a more common term among electricians.

And cable techs.

In my case, when I upgraded from Cat5 to Cat6, I taped on to the existing 5 and used it to pull the 6 through the attic and down the wall. In the attic, you usually use a string, with a weight of some kind attached (if it's a new install), to drop down the wall seal plate, which you've drilled a hole into, down to the hole you've already carved out for your cable box near the baseboard area.

Yep, normally fished indoors, and blown / sucked / pulled through underground (or above ground) conduit outside.

Reply on news.ycombinator.com