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Comment by jpeg_hero | Hacker News Reader

What kind of fiber could you even provision to the base station? 50gbit? 100gbit? Is that even possible?

10, 40 and 100 Gbit/s are common fiber speeds (as in, you can buy standardized parts from multiple vendors), but at least 100GbE is properly expensive (something in my brain says +100k€ per interface, but that figure probably is a few years old). And that's per individual fiberpair & wavelength, so it is easy to bundle up multiple channels.

I assume the quoted wireless speeds are for a single client under perfect conditions, what summed up bandwidth can a single tower support with multiple clients? 10 or 40G probably go a long way already.

100 GbE isn't that expensive. Transceivers for 100 GbE are in the $800 per port or so. CDW sells Proline 100 GbE transceivers for $300 a pop. It's a standard QSFP28 interface that is used for most of them. It carries 4x 25 GbE across the fibres.

They also make 100 GbE DAC cables.

Longer distances do cost more... Just looking around I found some 100GBASE-LR4 transceivers going for $6k a pop from Finisair... but at least you get to continue using your single mode fiber ;-)

If you're digging in the ground anyway, why not multiple fiber strands, and as many empty tubes as you can fit in there too? The digging is what costs (at least here in Denmark), not the materials.

I'm not arguing that we should use submarine style cables for base stations, but so you know what's possible: those cables (about 1 inch diameter) routinely do terabits per second.

You can get 10G Ethernet SFP+ modules using OM3 fiber for $100 these days. 12 strand outdoor fiber sells for $0.33/ft. Yes, neither of these is what you'd use as a backhaul link between cell sites, but it gives you an idea when you can do 60G over 300m distance for under $1,500 all in (assuming you already have SFP+ capable hardware at both ends). As others have stated, LR grade hardware has came way down in price just like the SR stuff has.

Stay away from multimode stuff, unless you are doing 100G inside data centers.

Single mode cable is cheaper and the optics are about the same for all use cases other than very short range 100G.

10G Etherner SFP+ modules aren't $100 a pop, it's more like $20-40 from third party providers. You can also do better than $0.33/ft for 12 count outdoor fiber.

100G optics are $400 for multimode and $1500 for singlemode. You gonna pay a lot more for switch or router ports tho.

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