Evolution of Data Networks

1
Performance of non-persistent CSMA
2
Performance of 1-persistent CSMA
S
0.53
1-Persistent CSMA
0.01
0.45
0.16
0.1
G
1
3
Achievable Throughputs
4
Frame Transfer delay for Ethernet
5
IEEE 802.3 MAC Frame
802.3 MAC Frame
2 or 6
1
2 or 6
2
4
7
Destination Address
Source Address
Information
FCS
Pad
Preamble
Length
SD
Synch
Start frame
64 to 1518 bytes

• Destination address is either single address
• or group address (broadcast 111...111)
• Addresses are defined on local or universal
  basis
• 246 possible global addresses

0
Single address
Group address
1
0
Local address
1
Global address
6
Ethernet frame (DIX Standard)
Ethernet Frame
2 or 6
1
2 or 6
2
4
7
Destination Address
Source Address
Information
FCS
Pad
Preamble
Type
SD
Start frame
Synch
64 to 1518 bytes