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 What is the relation between Jamsignal size and Minimum Frame Size in Ethernet(IEEE802.3) network? 

Several key parameters of CSMA/CD are needed to work correctly. 

First, there must be a carrier signal on the medium that other nodes can sense (thus the frame's preamble). 

Next, the transmitting node must be capable of completely transmitting the minimum packet size and reliably detecting whether a collision has occurred. This minimum transmission time necessary to transmit the minimum packet size is known as the slot time. For 10Mbps and 100Mbps Ethernet, the slot time is 512 bit times, which not coincidentally happens to be the minimum length of an Ethernet packet (64 octets is 512 bits). For gigabit Ethernet, the slot time is 4096 bit times. 
ollision detected procedure 

1. Continue transmission until minimum packet time is reached (jam signal) to ensure that all receivers detect the collision 
2. Is maximum number of transmission attempts reached? If so, abort transmission. 
3. Calculate and wait random backoff period 
4. Re-enter main procedure at stage 1 
jam signal is the same slot time 

Author	Message
manju Senior Member Joined: 20Feb2007 Online Status: Offline Posts: 221	Topic: Question on Ethernet Posted: 23Feb2007 at 4:57pm
	What is the relation between Jamsignal size and Minimum Frame Size in Ethernet(IEEE802.3) network? Several key parameters of CSMA/CD are needed to work correctly. First, there must be a carrier signal on the medium that other nodes can sense (thus the frame's preamble). Next, the transmitting node must be capable of completely transmitting the minimum packet size and reliably detecting whether a collision has occurred. This minimum transmission time necessary to transmit the minimum packet size is known as the slot time. For 10Mbps and 100Mbps Ethernet, the slot time is 512 bit times, which not coincidentally happens to be the minimum length of an Ethernet packet (64 octets is 512 bits). For gigabit Ethernet, the slot time is 4096 bit times. ollision detected procedure 1. Continue transmission until minimum packet time is reached (jam signal) to ensure that all receivers detect the collision 2. Is maximum number of transmission attempts reached? If so, abort transmission. 3. Calculate and wait random backoff period 4. Re-enter main procedure at stage 1 jam signal is the same slot time Post Resume: Click here to Upload your Resume & Apply for Jobs

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balu Senior Member Joined: 20Feb2007 Online Status: Offline Posts: 236	Posted: 23Feb2007 at 5:02pm
	Several key parameters of CSMA/CD are needed to work correctly. First, there must be a carrier signal on the medium that other nodes can sense (thus the frame's preamble). Next, the transmitting node must be capable of completely transmitting the minimum packet size and reliably detecting whether a collision has occurred. This minimum transmission time necessary to transmit the minimum packet size is known as the slot time. For 10Mbps and 100Mbps Ethernet, the slot time is 512 bit times, which not coincidentally happens to be the minimum length of an Ethernet packet (64 octets is 512 bits). For gigabit Ethernet, the slot time is 4096 bit times. ollision detected procedure 1. Continue transmission until minimum packet time is reached (jam signal) to ensure that all receivers detect the collision 2. Is maximum number of transmission attempts reached? If so, abort transmission. 3. Calculate and wait random backoff period 4. Re-enter main procedure at stage 1 jam signal is the same slot time
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