Interfaces and cables Flashcards
what does the RJ in RJ-45 mean
Registered Jack
What is Ethernet
Collection of network protocols/standards/ rather then a single protocol. Not one single thing.
What is a bit
Binary Digit. a value, represented by binary code, zeros or ones.
what is a Byte
8 bits equal 1 byte
How is speed measured?
In bits per second. kilo, mega, gigabits per second. not bytes
How is data measured?
Bytes
How much is one kilobit?
1,024 bits. 1/3 a page of text
How much is one megabit?
million 1,000,000 bits or 1000 kilobits
How much is one gigabit?
a billion bits 1,000,000,000/ 1000 megabits
terabyte
trillion bits, 1000 gigabits
what is IEE 802.3 standard?
1983 standard for ethernet.
what does the base in 10BASE-T mean?
baseband signaling/ can only carry ethernet
what does the T in 10BASE-T mean?
Twisted pair
10Base-T
Ethernet,
802.3i
100 M
10 Mbps
100Base-T
Fast Ethernet,
802.3u
100 Mbps
100 Meters
10000Base-T
Gigabit Ethernet,
802.3ab
100 M
1 Gbps
10GBase-T
10 Gig Ethernet,
802.3an
100 M
10 Gbps
UTP
un-shielded twisted pair. Twist protects against EMI
how many wires are in RJ-45?
8
What standards only use 2 pairs (4 wires out) of the 8?
10BASE-t 100BASE-T
What standards only use 4 pairs (8 wires)?
1000Base-T and 10GBase-T
which pins can PC transmit data on 10BASE-t 100BASE-T
1 and 2
Which pins does a switch receive data 0n 10BASE-t 100BASE-T
1 and 2
what is full duplex?
devices can send a receive data at the same time
which pins do PCs revice data on 10BASE-t 100BASE-T
4, 5
which pins do switch transmit data on 10BASE-t 100BASE-T
3, 6
Routers send data on which pins and receive data on which pins. 10BASE-t 100BASE-T
1, 2 and 4 ,5 same as a PCs
Straight through cable.
pin 1 connects to pin1, pin 2 connects to 2 and 3 to 3, 4 to 4. Connects different devices to each other.
Crossover cable
connects like devices. pins 1,2 connect to 3,6 wires are crossed over each other.
routers, firewalls and PC transmit and receive data on which pins?
1, 2 and receive on 3 and 6.
switches transmit data on what pins?
transmit 3,6 and receive 1, 2
Audio MDIX
Allows devices to detect which pins neighbors transmit data on, and can then adjust which pins they use to transmit and receive data.
1000Base-T and 10GBASE-T
all eight are used. 4,5 and 7 and 8
What can pairs of wires do in 1000Base-T and 10GBASE-T that 10BASE-t 100BASE-T cannot?
Each pair can transmit data bi-directionally. Meaning each pair is committed only to receving or transmitting data.
How many meters can a copper UDP be used?
100 meters
SFP Transceiver
Small form-factor pluggable
How do fiber optic cables work?
By sending lite over glass fibers.
Why do fiber optic cables have two connectors on both ends?
each ends have both receive and transmit connectors.
What are the four parts of a fiber cable?
1, fiber glass core which light travles.
- cladding that reflects light
- protective buffer that protects cable from breaking.
- outer jacker of the cable.
Multi mode fiber
Core is wider then single mode.
That allows multiple angles, (modes) of light to enter the fiberglass core.
allows longer cables than UTP but shorter cables than single-mode fiber.
cheaper then single-mode fiber(due to cheaper led-based SFP transmitters.
Not as fast or long as single mode.
single mode fiber
core i narrower then multimode,
light enters at a single angle(mode) from a laser based transmitter.
allows longer cables then multi and UDT cables.
more $ then multimode. due to laer-based SFP transmitters.
UTP vs fiber
UTP is lower cost, shorter max distance, vulnerable to EMI
You connect two old routers together with a UTP cable. however the data is not successfully sent and received between them.
Older routers do not have MDIX and can only communicate with a cross over cable.
most likey they are connected with stight through cable.
routers transmit data on which pins?
1, 2
to connect Lans that are 150 meters apart.
multi mode fiber. because its cheaper then single mode. supports distance over 150 meters
connections over 3K apart what kind of cable would you use.
Single mode. because multi mode does not support distances over 3K
can you connect like devices to stright through cables.
no.
most switches do not have enough SFP interfaces to support many end devices.
true
BIT is short for
binary digit. Smallest unit of data in computer.
one byte is equal to
8 bits, one character in a text doc.
