What kind of fiber *in* the home?
Submitted by doc on Mon, 12/05/2005 - 17:33.
A few days ago I wrote Building an Open Source Home over at Linux Journal. Lots of great responses there. Meanwhile, a new question has come up: If we want to future-proof the house as much as possible, we'll want fiber, right? The question is, what kind? My electrician — the guy who's doing the installation — says there are many kinds to choose from. Me, I have no idea. I'm hoping one or more of you folks do.
Some parameters to bear in mind.
First, there is no fiber in the neighborhood. Yet. The neighbors are stategizing about the best way to approach Verizon and Cox (our cable provider) with expressions of demand, as well as suggestions. Meanwhile, fiber-to-the-home is probably several years away. Which means we need to have pre-installed cable that's ready for whatever some carrier brings into our garage.
Second, while we may be able to run empty conduit from the garage down the the new house's patch panel downstairs (in the basement level, essentially), our ability to run conduit elsewhere in the house is limited. We'll run one to the room where servers will live (if I put them in, which is still an open strategic question); but there's no way to run any out to the two places where we'll have entertainment centers, or up to the offices (my wife's and mine) on the top floor. So we'll need to pre-install some kind of cabling.
Third, Cat6 cabling is running to every room in the house, as well as out to the garage where the services come in.
So. Ideas? Suggestions?
For what it's worth, here's the Froogle results page for fiber optic cable.
Fiber is not needed
If you feel you do want to pull fiber in your dream house, multimode is the way to go. With astar topology (home runs from server closet to each room) I'd suggest four fiber (simplex) strands:
TX, RX, and a backup TX, RX pair if something failes.
However, that's not what I'd do. CAT6 will allow you to easily deliver gigabit ethernet service. With a switch, traffic to the multimedia PC
does not travel the same path as traffic to your MP3 server, or you home security server.
There's a second good reason to not bother with expense of fiber everywhere. In teh planing horizon of your project, high speed wireless capacity will be going off teh charts vs. any possible application you can conceive.
In your wildest dreams a service provider may in teh future sell you a point to point 1 gigabit per second Ethernet feed.
So you internet access past teh wall of your house is capped at 1 Gbps.
Inside your house yu can use 802.11n which will provide about 100mbps. Over the next five years that goes up, probably to about 1 Gbps.
Fiber in the walls of your home wll rovide some cool braging rights. Nothing more.
-ron jeffries
http://blog.eronj.com
Good news, and bad news
62.5 micron multimode dual-fiber cable is currently the lowest common denominator for short haul "box to box" connectivity. If you install it "connectorized" have dual LC connectors put on it, but make sure there's enough slack in the run to allow you to pull out an extra foot or two at each end, if somewhere down the line you need to change connectors. Most multimode fiber transceivers can drive up to 300 meters of unspliced fiber without trouble.
The telco folks use single mode fiber, which handles much greater distances at the cost of much more fussyness of handling and more expensive transceivers to connect to it. But, I'd be rather nervous about pulling single mode on spec, in the expectation that e.g. Verizon would happily splice their drop to your internal fiber without hassle, rather than insisting on running a single unbroken span directly to their box using their fiber.
As for the places you have conduit, make sure to have your electrician leave an extra "pull tape", in case you need to pull additional wires later.
Not which but how many...
IMHO there is only the multi-mode choice (see above)...So the real question becomes... How many strands to pull. The best rule-o-thumb that I can offer (and use myself) is 100% over-pull. Figure out what you think you might use today or next week and then double it at least. Of course this is a sliding scale. 2 strands, add 8 more. 4 strands, add 12 more. 8, pull 16, 12 pull 24. If you plan on using 48 strands then you are already using more than "home" technology. :)
Best of luck...
William Meloney