Ethernet Standards and Cable Types Flashcards
What does CSMA/CD stand for?
Carrier Sense Multiple Access with Collision Detection
What does CSMA/CA stand for?
Carrier Sense Multiple Access with Collision Avoidance
What is IEEE 802.3 standard describe?
10Base-T - The T stands for twisted pair cable, and the maximum length of a 10Base-T copper cable is 100 meters. The 10 refers to the 10 Megabits per second capacity
What is the purpose of twisting the cable pairs in a Twisted Pair Cable?
Twisting cuts down on the possibility of electromagnetic interference.
True or False - The limit for a 10Base5 cable is 100 meters
False - The limit for 10Base5 is 500 meters
True or False - The limit of a 10Base2 cable is 100 meters
False - The limit of a 10Base2 cable is 185 meters
What does IEEE 802.3u describe?
Faster ethernet is defined by IEEE 802.3u and has a maximum capacity of 100Mbps. Faster Ethernet cables also have a max length of 100 meters.
How long is 100 meters in feet?
328 feet
what does IEEE 802.3z?
Gigabit Ethernet has a maximum capacity of 1000Mbps and is also expressed as 1 Gbps, the maximum cable length is 100 meters Additional standards for Gigabit Ethernet also include 802.3ab
What is a Cat 5 UTP?
A standard Ethernet cabling type is Category 5 Unshielded Twisted Pair which is commonly known as CAT 5 UTP. The connector on the end of a typical CAT 5 cable is a RJ-45 connector
What are the endpoints of a CAT5 wires called?
PINS
True or False - On a CAT5 cable, Pins 3 and 6 are used to Transmit and Pins 1 and 2 are used to Recieve.
False - Pins 1 and 2 Transmit and Pins 3 and 6 Receive
What is Crosstalk?
Crosstalk is caused by electromagnetic interference. Basically a signal crosses over from one pair of cables to another causing the signals to become unusable
What is NEXT?
Near End Cross Talk
What is FEXT?
Far End Cross Talk
What is NEXT caused by?
Generally caused by crossed for crushed wires, the conductors inside the wires don’t have to be exposed, but if the conductors are to close the signal traveling on one wire can actually interfere with the signal on another wire. Then year-end refers to the end of the cable being tested.
What is PSNEXT?
Power Sum Near End Crosstalk - refers to the calculation carried out when a NEXT test is run. When the NEXT results for each pair of wires is added, the result is the PSNEXT value.
Why would you use a straight through cable?
To connect to dissimilar devices together
Why would you use a Crossover cable?
To connect to similar devices together. (i.e. switch to switch)
Why would you use a Rollover cable?
Console Access
For a straight through cable, which pins are connected?
Pin 1 on one side is connected to Pin 1 on the other side, Pin 2 to Pin 2 and so on
True or False - Two switches can be connected together with a Straight Through Cable
False - A crossover cable would be used to connect similar devices to be connected
What is the Crossover Cable Pin Layout?
1-3
2-6
3-1
6-2
What is the pin layout for a rollover cable?
1-8
2-7
3-6
4-5
What are other names for a MAC Address?
Ethernet Address, NIC, Physical Address
What does a switch use a MAC address used for?
The MAC address is used by switches to send frames to the proper destination.
How many bits is a MAC Address?
48
What are the two parts of a MAC Adress?
The first part (i.e. the AA-BB-CC in AA-BB-CC-11-22-33), is the OUI (Organizationally Unique Identifier) The OUI is assigned to hardware vendors by the IEEE (Institute of Electrical and Electronics Engineers) Each OUI is only assigned to one vendor.
True or False - Vendors have only one OUI
False - Vendors can have many OUI’s
What is the Broadcast MAC address?
All F’s - FF-FF-FF-FF-FF-FF
What is the range of Multicast MAC addresses?
The first half of a multicast MAC address is always 0100.5e, the second half of a multicast MAC message will fall in the range of 00-00-00 through 7f-FF-FF - Make sure you watch that 7!!
