Which is the protocol used in ethernet. (CSMA/CD) Why is it called so ?

Which is the protocol used in ethernet. (CSMA/CD) Why is it
called so ?

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Which is the protocol used in ethernet. (CSMA/CD) Why is it called so ?..

Answer / vijaysivadas

CSMA/CD -Its called the carrier Sense Multiple
Access /Collision Detection

Each interface must wait until there is no signal on the
channel, then it can begin transmitting. If some other
interface is transmitting there will be a signal on the
channel, which is called carrier. All other interfaces must
wait until carrier ceases before trying to transmit, and
this process is called Carrier Sense.

All Ethernet interfaces are equal in their ability to send
frames onto the network. No one gets a higher priority than
anyone else, This is what is meant by Multiple Access.
Since signals take a finite time to travel from one end of
an Ethernet system to the other, the first bits of a
transmitted frame do not reach all parts of the network
simultaneously. Therefore, it's possible for two interfaces
to sense that the network is idle and to start transmitting
their frames simultaneously. When this happens, the
Ethernet system has a way to sense the "collision" of
signals and to stop the transmission and resend the frames.
This is called Collision Detect.

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Which is the protocol used in ethernet. (CSMA/CD) Why is it called so ?..

Answer / anil

CSMA/CD is a media access control mechanism used in Ethernet
to recover from frame collision. The following steps are
followed to recover from a collision.
Step 1: Before an Ethernet device sends a frame on the
Ethernet cable, it listens to find if another device is
already transmitting a frame (Carrier Sense).
Step 2: Once the device finds that other devices are not
transmitting any frame, it starts transmitting the frame. If
two devices detect that the Ethernet cable is free at the
same time, then both will start transmitting the frames
(Multiple Access). This will result in collision.
Step 3: The Ethernet devices while transmitting the frames,
also listen for the collision. (Collision Detect).
Step 4: If they detect a collision, both the devices stop
sending the frame (back off).
Step 5: They retry the transmission after a logarithmic
time-out period. This process is repeated till the frame is
transmitted successfully, for a maximum of 16 times. The
frame is discarded after the 16th retry.