cooling door

Mon Mar 31 14:53:32 UTC 2008

On Sat, Mar 29, 2008 at 3:04 PM, Frank Coluccio <frank at dticonsulting.com>
wrote:

>
> Michael Dillon is spot on when he states the following (quotation below),
> although he could have gone another step in suggesting how the distance
> insensitivity of fiber could be further leveraged:

Dillon is not only not spot on, dillon is quite a bit away from being spot
on. Read on.

>
>
> >The high speed fibre in Metro Area Networks will tie it all together
> >with the result that for many applications, it won't matter where
> >the servers are.
>
> In fact, those same servers, and a host of other storage and network
> elements,
> can be returned to the LAN rooms and closets of most commercial buildings
> from
> whence they originally came prior to the large-scale data center
> consolidations
> of the current millennium, once organizations decide to free themselves of
> the
> 100-meter constraint imposed by UTP-based LAN hardware and replace those
> LANs
> with collapsed fiber backbone designs that attach to remote switches
> (which could
> be either in-building or remote), instead of the minimum two switches on
> every
> floor that has become customary today.

Here is a little hint - most distributed applications in traditional
jobsets, tend to work best when they are close together. Unless you can map
those jobsets onto truly partitioned algorithms that work on local copy,
this is a _non starter_.

>
>
> We often discuss the empowerment afforded by optical technology, but we've
> barely
> scratched the surface of its ability to effect meaningful architectural
> changes.

No matter how much optical technology you have, it will tend to be more
expensive to run, have higher failure rates, and use more power, than simply
running fiber or copper inside your datacenter. There is a reason most
people, who are backed up by sober accountants, tend to cluster stuff under
one roof.

>
> The earlier prospects of creating consolidated data centers were once
> near-universally considered timely and efficient, and they still are in
> many
> respects. However, now that the problems associated with a/c and power
> have
> entered into the calculus, some data center design strategies are
> beginning to
> look more like anachronisms that have been caught in a whip-lash of
> rapidly
> shifting conditions, and in a league with the constraints that are imposed
> by the
> now-seemingly-obligatory 100-meter UTP design.

Frank, lets assume we have abundant dark fiber, and a 800 strand ribbon
fiber cable costs the same as a utp run. Can you get me some quotes from a
few folks about terminating and patching 800 strands x2?

/vijay

>
>
> Frank A. Coluccio
> DTI Consulting Inc.
> 212-587-8150 Office
> 347-526-6788 Mobile
>
> On Sat Mar 29 13:57 ,  sent:
>
> >
> >> Can someone please, pretty please with sugar on top, explain
> >> the point behind high power density?
> >
> >It allows you to market your operation as a "data center". If
> >you spread it out to reduce power density, then the logical
> >conclusion is to use multiple physical locations. At that point
> >you are no longer centralized.
> >
> >In any case, a lot of people are now questioning the traditional
> >data center model from various angles. The time is ripe for a
> >paradigm change. My theory is that the new paradigm will be centrally
> >managed, because there is only so much expertise to go around. But
> >the racks will be physically distributed, in virtually every office
> >building, because some things need to be close to local users. The
> >high speed fibre in Metro Area Networks will tie it all together
> >with the result that for many applications, it won't matter where
> >the servers are. Note that the Google MapReduce, Amazon EC2, Haddoop
> >trend will make it much easier to place an application without
> >worrying about the exact locations of the physical servers.
> >
> >Back in the old days, small ISPs set up PoPs by finding a closet
> >in the back room of a local store to set up modem banks. In the 21st
> >century folks will be looking for corporate data centers with room
> >for a rack or two of multicore CPUs running XEN, and Opensolaris
> >SANs running ZFS/raidz providing iSCSI targets to the XEN VMs.
> >
> >--Michael Dillon
>
>
>
>
>
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