In article , [EMAIL PROTECTED] says... > Ok I have spent ages trying to find an answer to this question, and probably > only added to my confusion. You know how it is you spend ages looking at > something and become snow blind or get tunnel vision or whatever, but I > cannot see the answer to the following: > > How far does a bit travel in say 1 second or put another way how long does a > bit take to travel a certain distance ? > > I understand, or think I do that if the line is say 128kbps then I can, in > theory at least, expect 128,000 (approx) bits start down that line every > second. > > But how long do they take to reach the other end, assuming a point to point > link and both ends being the same speed, obviously. > > There has to be a nice simple formula for this somewhere, you know the sort > of thing x= line speed, y = distance z = time etc > > Any ideas or poitners would be appreciated > > Thanks It depends on the medium used. The rough calculation for the propagation of an electromagnetic signal in wire is 66% of the speed of light in a vacuum. Or 186000 x 2/3 = 124000 miles/sec.
Measurement on Cat5 are very close to this number. Coax is different. More on the order of 55% of the speed of light in a vacuum. If you are very interested in this, check out xxx.lanl.gov/abs/physics/0201053 -- Wes Knight MCT, MCSE, CNE, CCNP, ASE, etc. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=41197&t=41192 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
