C3. Your favorite cables Flashcards
What is the coax cable? How is it constructed? What is it made of?
Coax stands for coaxial; It has a center conductor made of copper and an outer plastic jacket with a braided shield over copper
What kind of plastic is used for coax cables (and where is it used?)
PVC vs FEP; FEP is just good old teflon. Teflon is a plenum-rated coating; good replacement for all other media because it’s safe in case of fire
What is one example of a coax cable?
Thinnet - thin ethernet - is a thin coaxial cable; Thinnet is used with the BNC connectors on both sides…
What are the BNC connectors?
BNC babies are a kind of coaxial connectors
What type of coaxial connectors are used on cable TV?
F-type
What’s a twisted pair cable? What are the two kinds of twisted pair cables?
A cable with … deep breath! multiple!! twisted pairs. There are two kinds of cable - STP and UTP; some are shielded - hence a shielder twisted pair or STP. Some are unshielded - UTP.
Why is UTP so popular? Where is it used?
UTP is used in Ethernet cabling!
What is crosstalk?
Crosstalk is a kind of interference that occurs when electromagnetic signals are conducted on copper wires in close proximity to one another; the interference is minimized by twisting the cables together
What are twisted pair cables good for?
- They’re cheaper than other types of cabling
- They’re easy to work with
- They allow transmission rates that were impossible 10 years ago
What is category 1 of twisted wire pairs? What’s its conventional name? What kind of signal frequency range does it support?
Two twisted wire pairs (2^1 lol) POTS - plain old telephone service; it supports signals limited to 1 MHz frequency range
What is category 2 of twisted wire pairs? What kind of speed and signal frequency range does it support?
Four twisted wire pairs. This category handles transmissions up to 4 Mbps, with a frequency limitation of 10 MHz
What is category 3 of twisted wire pairs? What kind of speed and signal frequency range does it support? What is it used for?
Four twisted wire pairs, three twists per foot. This category handles transmissions up to 10 Mbps and 16 MHz
It’s used in telecommunication equipment and is totally obsolete for networks
What is category 4 of twisted wire pairs? What kind of signal frequency range does it support?
Four twisted wire pairs. Up to 20 MHz. Obsolete
What is category 5 of twisted wire pairs? What kind of cable is it used for? What kind of signal frequency range does it support?
Four twisted wire pairs; used for 100BaseTX; rated for 100 MHz
What is category 5e of twisted wire pairs? What kind of cable is it used for? What kind of signal frequency range does it support? What’s special about it!
Has four twisted wire pairs; recommended for 1000BaseT; rated for 100 MHz
It’s capable of handling disturbance on each pair that’s caused by transmitting on all four pairs at the same time - so we can use it with Ethernet - and this is the lowest category good for Ethernet!
What is category 6 of twisted wire pairs? What kind of cable and signal frequency range does it support?
Four twisted wire pairs, used for 1000BaseTX and rated for 250 MHz.
What is category 6A of twisted wire pairs? What kind of speed and signal frequency range does it support?
Four twisted wire pairs, used for 10GBaseT for up to 100 meters; rated for 500 MHz.
What is category 7 of twisted wire pairs? What is the speed that it supports and across what distance does it support it?
Four twisted wire pairs; Allows 10 Gigabit internet over 100 meters of copper cabling
What kind of connectors typically go with twisted pair cables?
RJ - registered jacks!
Name the three kinds of RJ connections and what they are good for
1) RJ-11 for phones
2) RJ-45 for LANs with short distances
3) RJ-48c for T1 connections
Describe the fiber-optic cables - how do they essentially transmit signals? What are the two kinds of transmission (but not two types of cables)?
They transmit digital signals using eight impulses rather than electricity; light impulses are carried on either glass or plastic core
- Glass core is better for distance
- Plastic is better for … cost, of course :)