RE: High Density Multimode Runs BCP?
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Thor Lancelot Simon Sent: Wednesday, January 26, 2005 2:09 PM To: nanog@merit.edu Subject: Re: High Density Multimode Runs BCP?
On Tue, Jan 25, 2005 at 07:23:17PM -0500, Deepak Jain wrote:
I have a situation where I want to run Nx24 pairs of GE across a datacenter to several different customers. Runs are about
200meters max.
When running say 24-pairs of multi-mode across a datacenter, I have considered a few solutions, but am not sure what is
common/best practice.
I assume multiplexing up to 10Gb (possibly two links thereof) and then back down is cost-prohibitive? That's probably the "best" practice.
I think he's talking physical plant. 200m should be fine. Consult your equipment for power levels and support distance. Inside plant, dedicated fiber tray Nothing wrong with running a bundle of MM with the SM bundles. This method usually uses fiber shelfs with either pig tailed (factory) or fusion spliced(best) method. Inside plant, no tray, fiber trough Use factory terminated strands(patch) only and save yourself aggravation and get better reliability. Run it loose in the trough from source to destination ports. Inside plant, no tray, no fiber trough Use factory strands(patch) and run it inside a 1/4" or larger innerduct from source to destination ports. Spiral wrap is always recommended on the "last 7'" and some sort of bracing near the port should be provided. Consult the cable manufacture for proper bend radius. Avoid zip ties if possible. Vibration and other factors make them not desirable. There's a multitude of combinations of the above. Without knowing the facility layout and the cross connect/inter connect standard, it's hard to speculate. (the above is as close to a BCP as you can get. Fairly typical central office standards via Bellcore. Er. Telcordia. YMMV -M<
On Wed, Jan 26, 2005 at 02:49:29PM -0500, Hannigan, Martin wrote:
When running say 24-pairs of multi-mode across a datacenter, I have considered a few solutions, but am not sure what is
common/best practice.
I assume multiplexing up to 10Gb (possibly two links thereof) and then back down is cost-prohibitive? That's probably the "best" practice.
I think he's talking physical plant. 200m should be fine. Consult your equipment for power levels and support distance.
Sure -- but given the cost of the new physical plant installation he's talking about, the fact that he seems to know the present maximum data rate for each physical link, and so forth, I think it does make sense to ask the question "is the right solution to simply be more economical with physical plant by multiplexing to a higher data rate"? I've never used fibre ribbon, as advocated by someone else in this thread, and that does sound like a very clever space- and possibly cost-saving solution to the puzzle. But even so, spending tens of thousands of dollars to carry 24 discrete physical links hundreds of meters across a datacenter, each at what is, these days, not a particularly high data rate, may not be the best choice. There may well be some question about at which layer it makes sense to aggregate the links -- but to me, the question "is it really the best choice of design constraints to take aggregation/multiplexing off the table" is a very substantial one here and not profitably avoided. Thor
participants (2)
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Hannigan, Martin -
Thor Lancelot Simon