cable standards

cjthedj45

Hi,

I'm writing the network+ exam on Wednesday and I'm having a few problems with the cable standards. I'm using a few different resources for my study and it seems they conflict slightly. Here is an example.

1000 base SX max data transmission on MMF is 260 Meters.

However on another resource I'm given the below example.

1000 base SX max data transmission over 500 meters.

The only difference is that MMF is mentioned in the first example. Does this mean that the 2nd example is refering to the use of SMF. I'm confused I would really appreciate it if any of you know the accurate information for cable standards particulary fibre optic. My head is all over the place at the moment and when I'm taking the practice exams I'm not sure what the correct answer is regards to cable standards. Does anyone have any easy way to memroise this Thanks in advance

cjthedj45

Hi,

Its me again I have just found another conflict whilst doing my preperation for the exam on Wedensday. Example below.

One resource says that a 1000base CX max cable length is 25 meters.

another resource says 1000base CX cat 6 is 100 meters max length.

These cable standards are melting my brain please can anyone offer any guidance. Thanks

macdude

http://en.wikipedia.org/wiki/Cat_6


"As with all cables defined by TIA/EIA-568-B, the maximum allowed length of a Cat-6 horizontal cable is 90 meters (295 feet). A complete channel (horizontal cable plus cords on either end) is allowed to be up to 100 meters in length, depending upon the ratio of cord length:horizontal cable length."

cjthedj45

Hi Macdude,

Thanks for your reply but is what you have said relevant to the test? Your response has confused me more because you have noted that the cable length is 90 meters but 100 meters if it has cords on the end. I have never heard of cords adding length to cables in either of my study resources. What I would find really useful is a list of the exact cable standards that I will be tested on. My study resources seem to conflict hence the reason for me reaching out on this forum. If anyone could put any further clarity on this issue it would be much appreciated. Thanks

tonyg

I have also found that there are many conflicts when it comes to cable standards. I for one am going to stick with the break out on cable standards in "Network + All In One" and the Tech notes here on this site.

As for the 90 -v- 100 issue I think it is mentioned in the All In One that when you make your cable run from the server room to the node you also have to take into account how long the patch cable is from the client machine to the wall jack and how long the patch cables are in the server room. The bottom line is if you were to see a question like; "the length of the cable run to the node is 95 meters, the patch cable in the server room is 3 meter long and the patch cable connecting the node to the wall jack is 4 meters long, can you use cable type x?"

The answer would be no. The total amount of cable exceeds the 100 meter limitation.

ksimpson

Anytime you see SX (*short haul) .. that means MMF. LX (*long haul) means SMF

Correct me if I'm wrong. Just how I learned it.

A LX Module needs SMF and a SX Module needs MMF.