Re: networking installation. cables v hubs

Robbie wrote:

> Question: All cable, or use less cables and more hubs?
>
>
>
> Situation: Installing an Ethernet network for 20 users in a building which
>
> has 3 floors, and is 50m Long. Offices are grouped into 4 main areas, 4 on
>
> Grnd Floor, 5 on 1st Floor, 5 on 2nd Floor, 6 on 2nd Floor at other end of
>
> building.
>
>
>
> Option A:
>
>>From the central point where the Server is located, run Cat 5e cabling to
>
> all points where a network point is required (involving some long and fairly
>
> tortuous cable runs through the building). Use 24 Port 10/100 Switch located
>
> near the Server.
>
>
>
> Advantages - this gives every point maximum throughput, and keeps hardware
>
> in one area away from users.
>
> Disadvantages: Requires more time to pull all the cable to all points, thus
>
> relatively high installation time.
>
>
>
> Option B:
>
>>From central point where the server is located, run Cat 5e cabling to only
>
> the major areas of the building (i.e. 1 cable to 1st floor offices, another
>
> to 2nd floor offices, another to 2nd floor office at other end of building,
>
> etc) then place smaller (8 Port?) 10/100 Network Switch near Server, and
>
> place an 8 or 4 Port hub (or possibly Switch, as these are almost as cheap
>
> as Hubs now) in each "office group" and run cabling from this to the wall
>
> sockets in each individual office.
>
>
>
> Advantages: Much less time spent pulling long cable runs through the
>
> building which, so lower installation time/cost.
>
>
>
> Disadvantages: Higher equipment cost. Users in each area share one Ethernet
>
> cable from their local Hub, through the Switch, to other Hubs. Possible
>
> bottlenecks, possible technical problems with number of hops?
>
>
>
>
>
> Question: With the above information can anyone experienced in network cable
>
> installations advise which method best for us, and are there any technical
>
> issues raised by having 4 Hubs, 1 Switch in terms of Ethernet limitations
>
> either physical or at the byte level?
>
> We are aware that by cabling EVERY port direct to a 24 Port Switch, every
>
> user gets the best throughput, but as expected network traffic should be
>
> low, will there be any problem using fewer "backbone" cables and splitting
>
> the data off closer to the users by having a Hub per group of offices?
>
>
>
> Thanks in advance for ANY advice
>
> Robbie
>
>
>
>

I think you've identified the issues correctly. Unfortunately, the
necessary conclusion is that the amount of contention will depend on
the usage pattern. My first inclination is that Option B will be
fine for a typical office (and is similar to what I have here). If
you're doing video or something else with large bandwidth requirements,
however (e.g. diskless clients), you may need to pull more cable.

The best advice I can give you is to try to estimate peak bandwidth
requirements for each leg (based on your particular anticipated
application mix) and act accordingly.

If your server just has one 10/100 NIC, you won't get any more total
throughput than it can provide, so IT may be the ultimate bottleneck.
Adjust that thought if you have more than one server.

Also consider that Gigabit networks are coming down in price and may
allow cheap increase in the trunk speeds without recabling fairly soon.

Switches are cheap enough now that I doubt there's much use for hubs
any more.

That's my 2 cents.





CJT