Basic advice for fiber in the home?

[jester]

I've been planning on upgrading my home network to 10GbE for a while, with Mikrotik hardware. Nothing will be particularly complicated; I'll need two or three runs of cable that will be 10–20m at most, a couple of very short runs of patch cable, and I think three switches. My assumption is that connections from switch to switch will be via cable into the SFP+ ports, but the actual link to the various machines will be into standard RJ45 jacks.

Now that I'm looking into the details, I'm getting overwhelmed by how complicated this all seems, and I can't find any straightforward explanation of what to do. Instead there are lists of a dozen different incompatible kinds of cable, a dozen different incompatible connectors, and seemingly thousands of transceivers.

I'm not really interested in the complete history of connector types, or a breakdown of the best cables for 20km runs. I just want something like "Use LC duplex connectors for everything, OM3 multimode cable for everything, and one of these few transceivers depending on whether it's connecting fiber or copper." Is there some place to get clear advice about what to do?

 

[reasonsandreasons]

If you're running cables through walls, you probably want to go with OS2 single-mode duplex LC-to-LC fiber. Single mode fiber is the most adaptable format out there, and can carry signals up into the 400 Gigabit range over simple duplex cables. Multimode fiber requires cables with more fibers to do that above 25 Gigabit speeds. The upshot is that with single-mode fiber any future speed upgrades will require changing the receivers, not re-running the fiber. The con with single-mode is that the transceivers are moderately more expensive, but 10GBASE-LR transceivers are cheap enough on the secondary market that it's not a real worry.

If your switch's 10 gigabit ports are all SFP+, you'll need to use a 10GBASE-T transceiver to get to the machines themselves. These are all pretty interchangeable with Mikrotik hardware, but make sure you get one that supports 2.5G and 5G if that's important to you. The STH guide is good on this front.

 

[Fallen Kell]

Also in terms of "basic advice" for fiber in the home, run conduit. If you don't have the tools and experience to splice fiber or install terminations, you will probably be running pre-terminated fiber, and as a result the width of the conduit will need to be larger. You also need to pay attention to any/all bends that you make with the conduit so that they are all gentle, sweeping bends to allow for both the optical cable to not get crimped, but also enough space for the end termination plug to be able to fit through the bend.

So make you life easier, run the conduit and secure it into place, paying attention to the bends. Then blow a pull string into the conduit (don't skimp on the length of the string, leave at least double the length outside one of the ends of the conduit so you still have the string reachable on both ends of the conduit after performing the first pull, this way you can pull the string back through the conduit and perform a second pull in the future cause in 10 years you might need additional fiber cables).

 

[nexox]

My assumption is that connections from switch to switch will be via cable into the SFP+ ports, but the actual link to the various machines will be into standard RJ45 jacks.

If you don't already have 10GBaseT ports on your machines and you intend to buy 10G NICs, save some power (plus probably money) and buy cards that have SFP+ ports, just make sure to check the model to ensure it doesn't enforce a vendor lock on SFP+ modules, unless you want the added annoyance of buying modules that match.

For short runs use DACs (copper cable with SFP+ connectors,) for longer runs that you don't need to pull through a wall there's a post in the Great Deals section on cheap 7 meter AOCs (fiber with SFP+ connectors permanently attached.)

 

[jester]

Thanks for these suggestions. I won't be running the cable myself, I'll get a guy to do it, I just need to know what to tell him. Two of the runs will be fairly easy (along baseboards); there's one place where there's an existing conduit, and we have to figure out whether it'll be possible to run new cable through it. (If not, I won't be able to do anything about that run.)

 

[Tech Junky]

@jester

It's all a planning game when it comes to this sort of thing. Plenty of info above tracks though and should be helpful in planning how/where to run the new fiber. If you have the conduit in place though it's easier to come back and change from say OM3 to SM if you find the need to.

I would probably just stick with OM3/4 though as it handles plenty of bandwidth. Sticking with the SR modules will tend to be cheaper as well. CU is CU though and it tend to run hotter vs optics in the PC side.

For the conduit just hire an electrician to run the pipes and secure them. If you have the space for a larger diameter that allows you to feed the fibers yourself you can save on that end of the install. It's all a hassle unless you do it for a living but, once you get the foundation in place it's easy to manage yourself. In most cases it's probably easier to run a pair of fibers in each tube at the same time so you have a backup if one doesn't work the other might and then threading a replacement backup will be easy as well since you just attach the new to the bad and pull it through.

The biggest issue though to keep an eye on is to keep the connector types the same across all legs so you don't end up with odd and ends of optics to deal with. Order what you need and a couple of spares in case there's a lack of QC on them. Easier to send back extras than to wait on another shipment.

https://www.servethehome.com/sfp-to-10gbase-t-adapter-module-buyers-guide/

 

[mattventura]

Seconding the suggestion to use single-mode fiber. LC SMF will not be obsolete for a very long time. It's already good for 400gb+, and will continue to be supported because ISPs don't want to have to upgrade 80km fiber runs. Looking at ebay prices, 10gbase-LR (or LR-lite) transceivers are $5-6 on the bay, 25Gbase-LR is $9, 40g is $10-15, and 100g is $35.

 

[klui]

There are all sorts of arguments used to justify single mode or multimode. Multimode will support 100G or greater but requires OM5 and MPO16. Really think about how long you will use 10G before you have FOMO and want something faster. Whatever you choose should be fine for 10G as long as you choose LC duplex. Just realize if you go with multimode anything faster than 40G will require OM5 and expensive transceivers. Who knows what will work by the time they come down in price. The reason why folks recommend single mode is you can get really inexpensive ($5) transceivers that support 100G today.

Even though you won't be pulling the wires, you need to understand how it's done so you know it's been installed properly. Most likely you will be purchasing pre-terminated bend insensitive fiber. All new fiber optic cables should be bend insensitive. Just be aware if you buy new old stock. To get them pulled through conduit you need to either use a pull sock of some sort but traditional ones require a large diameter conduit, like 2 inches. If you were pulling MPO patch cords there are pull eye caps made for that purpose. I can't find anything for LC connectors. You can attach an LC coupler to your fiber connector with a cap on the other end and use that as a pull cap. Just get ones with regular flanges so you could attach to its holes. https://www.dintek.com.tw/media/com...image_5826891c60d32_adaptor-9-max-800x800.png While you're at it, pull another pair as spare through your conduit.

Understand the fiber's tensile load rating you buy. And while they're on par with copper they should not be fished through a home's structure bare. The crevices of a home may have an effect on the cable's compression rating which are quite low. While fiber's tensile load ratings are roughly 30 ft-lb, their compression rating is less than 1 ft-lb for a patch cord. Because you'll be pulling from the connector the tensile rating should be de-rated as well. Tensile ratings take into consideration the cable's strengthening member. How much to de-rate is up for debate because the vendors don't provide figures for completed assemblies.

What you don't want your contractor do is to use a metal pull grip. Grips are meant to pull a large bundle of cables but they will crush fiber due to how they work. They're used to pull loose fiber meant to be terminated after they've been pulled. And even then additional fiber past the grip need to be discarded.

There are many aspects one needs to consider before plunging into fiber. STH has some articles at the main site but unfortunately nothing to aide in their installation nor what product one should choose over another. You will need to do your research and make the best decision for your use case. There isn't one place that has all this stuff documented.