I have some things to add to that: a) My experience is that potential fiber distances are fairly standard, regardless of the manufacturer.
b) Do not try to put ethernet on CAT3 unless you are REALLY deperate. It will *hypothetically* work, but it is out of spec. Since it is out of spec do not assume that the endpoints will sync up; whether or not they do is hardware specific. I have recent experience in this area - my work-issued laptop (a Dell Latitude E5500 with integrated Broadcom gigabit) will not sync up to a Cisco Catalyst 2950-12 switch over CAT3. The same set of cables, switch and switch port sync up fine with my previous home desktop (Intel DG33BU motherboard with integrated Intel gigabit ethernet). On 2/2/2011 12:55 PM, Ben Scott wrote: > On Wed, Feb 2, 2011 at 10:40 AM, Holstrom, Don <[email protected]> wrote: >> I work in an old Museum here in the District. My runs are very long, one is >> over 700 feet and gives me a problem every now and then. Is it worthwhile to >> switch out our CAT4&5 and go to CAT6a (there is something above 6a?) > > As everyone else has said, twisted pair Ethernet is limited to 100 > meters (~328 feet) in the spec. This is independent of speed -- > anything from gigabit to ten megabit, CAT3 to CAT6A, the limit is 100 > meters. > > Repeaters or switches along the way will let you extend that > distance. I'd suggest switches; that keeps the path full-duplex and > you don't have to worry about repeater hop limits. > > Fiber can go longer still. How long depends on the type and grade > of fiber. Exact numbers seem to vary by manufacturer. HP (ProCurve) > ranges from 220 meters (721 feet) on the cheapest to 70 kilometers (43 > miles) on the high end. (http://tinyurl.com/4kdkoda) > > If you don't have existing modular ports (SFP) in your switches, you > can get single-port media converters for small money. Installation is > usually the pricey part. > > I've read nothing good about Ethernet-over-power-lines. > > The grade of UTP mainly determines maximum speed: > > CAT3 = 10 megabit > CAT5 = 100 megabit > CAT5E = 1 gigabit > CAT6 = waste of money > CAT6A = 10 gigabit > > The 100 meter limit comes about due to the time it takes for signal > propagation in a copper medium. In the event of a collision > detection, a "jam signal" is transmitted. There has to be enough time > for the jam signal to reach all other nodes before the next > transmission opportunity. > > Since it's a timing limit, on a full duplex point-to-point link > (i.e., most links these days), you can actually go a longer distance > and still have it sometimes sort-of work. However, you're > out-of-spec, so anything can happen. It might fail on alternating > Tuesdays, or it might cause demons to fly out of your nose. -- Phil Brutsche [email protected] ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to [email protected] with the body: unsubscribe ntsysadmin
