Ethernet data rate period

Data rate
Period
100M 1G 10G 40G 100G
bits bytes bits bytes bits bytes bits bytes bits bytes
10ns 1 0.125 10 1.25 100 12.5 400 50 1K 125
100ns 10 1.25 100 12.5 1K 125 4K 500 10K 1.25K
1us 100 12.5 1K 125 10K 1.25K 40K 5K 100K 12.5K
10us 1K 125 10K 1.25K 100K 12.5K 400K 50K 1M 125K
100us 10K 1.25K 100K 12.5K 1M 125K 4M 500K 10M 1.25M
1ms 100K 12.5K 1M 125K 10M 1.25M 40M 5M 100M 12.5M
10ms 1M 125K 10M 1.25M 100M 12.5M 400M 50M 1G 125M
100ms 10M 1.25M 100M 12.5M 1G 125M 4G 500M 10G 1.25G
1s 100M 12.5M 1G 125M 10G 1.25G 40G 5G 100G 12.5G
1m 6G 750M 60G 7.5G 600G 75G 2.4T 300G 6T 750G
1h 360G 45G 4.6T 250G 36T 4.5T 144T 18T 360T 45T
1d 8.64T 1.08T 86.4T 10.8T 864T 108T 3.456P 432T 8.64P 1.08P

Ethernet frame and packet

Ethernet frame and packet sizes

Ethernet frame and packet sizes
 
Default VLAN Q-in-Q MPLS
Frame Packet Frame Packet Frame Packet Frame Packet
Minimum 64 84 64 84 64 84 64 84
Maximum 1518 1538 1522 1542 1526 1546 1530 1550

Minimum default ethernet packet and frame

Minimum default ethernet packet and frame
 
Interframe Gap Preamble DST MAC SRC MAC Type Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 2 Bytes Min 46 bytes 4 bytes
Layer 2 Ethernet frame
Layer 1 Ethernet packet

Minimum default ethernet frame size: 64 bytes

Minimum default ethernet packet size: 84 bytes

Minimum vlan tagged ethernet packet and frame (IEEE 802.1Q)

Minimum vlan tagged ethernet packet and frame
 
Interframe Gap Preamble DST MAC SRC MAC 802.1Q Tag Type Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 4 bytes 2 Bytes Min 42 bytes 4 bytes
Layer 2 Ethernet vlan tagged frame
Layer 1 Ethernet vlan tagged packet

Minimum vlan tagged ethernet frame size: 64 bytes

Minimum vlan tagged ethernet packet size: 84 bytes

Minimum Q-in-Q tagged ethernet packet and frame (IEEE 802.1ad)

Minimum Q-in-Q tagged ethernet frame
 
Interframe Gap Preamble DST MAC SRC MAC Metro Tag Customer Tag Type Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 4 bytes 4 bytes 2 Bytes Min 38 bytes 4 bytes
Layer 2 Ethernet Q-in-Q tagged frame
Layer 1 Ethernet Q-in-Q tagged packet

Minimum Q-in-Q tagged ethernet frame size: 64 bytes

Minimum Q-in-Q tagged ethernet packet size: 84 bytes

Minimum MPLS tagged ethernet packet and frame

Minimum MPLS tagged ethernet packet and frame
 
Interframe Gap Preamble DST MAC SRC MAC Type MPLS Label MPLS Label MPLS Label Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 2 bytes 4 bytes 4 bytes 4 bytes Min 34 bytes 4 bytes
Layer 2 Ethernet MPLS tagged frame
Layer 1 Ethernet MPLS tagged packet

Minimum MPLS tagged ethernet frame size: 64 bytes

Minimum MPLS tagged ethernet packet size: 84 bytes

Maximum default ethernet packet and frame

Maximum default ethernet packet and frame
 
Interframe Gap Preamble DST MAC SRC MAC Type Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 2 Bytes 1500 bytes 4 bytes
Layer 2 Ethernet frame
Layer 1 Ethernet packet

Maximum default ethernet frame size: 1518 bytes

Maximum default ethernet packet size: 1538 bytes

Maximum vlan tagged ethernet packet and frame (IEEE 802.1Q)

Maximum vlan tagged ethernet packet and frame
 
Interframe Gap Preamble DST MAC SRC MAC 802.1Q Tag Type Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 4 bytes 2 Bytes 1500 bytes 4 bytes
Layer 2 Ethernet vlan tagged frame
Layer 1 Ethernet vlan tagged packet

Maximum vlan tagged ethernet frame size: 1522 bytes

Maximum vlan tagged ethernet packet size: 1542 bytes

Maximum Q-in-Q tagged ethernet packet and frame (IEEE 802.1ad)

Maximum Q-in-Q tagged ethernet frame
 
Interframe Gap Preamble DST MAC SRC MAC Metro Tag Customer Tag Type Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 4 bytes 4 bytes 2 Bytes 1500 bytes 4 bytes
Layer 2 Ethernet Q-in-Q tagged frame
Layer 1 Ethernet Q-in-Q tagged packet

Maximum Q-in-Q tagged ethernet frame size: 1526 bytes

Maximum Q-in-Q tagged ethernet packet size: 1546 bytes

Maximum MPLS tagged ethernet packet and frame

Maximum MPLS tagged ethernet packet and frame
 
Interframe Gap Preamble DST MAC SRC MAC Type MPLS Label MPLS Label MPLS Label Data CRC
12 Bytes 8 Bytes 6 bytes 6 bytes 2 bytes 4 bytes 4 bytes 4 bytes 1500 bytes 4 bytes
Layer 2 Ethernet MPLS tagged frame
Layer 1 Ethernet MPLS tagged packet

Maximum MPLS tagged ethernet frame size: 1530 bytes

Maximum MPLS tagged ethernet packet size: 1550 bytes

Smallest size of Ethernet frame

The minimum frame payload is 46 Bytes (dictated by the slot time of the Ethernet LAN architecture). The maximum frame rate is achieved by a single transmitting node which does not therefore suffer any collisions. This implies a frame consisting of 72 Bytes (see table below) with a 9.6 µs inter-frame gap (corresponding to 12 Bytes at 10 Mbps). The total utilised period (measured in bits) corresponds to 84 Bytes.

Ethernet frame parts
Frame Part Minimum Size Frame
Inter Frame Gap (9.6µs) 12 Bytes
MAC Preamble (+ SFD) 8 Bytes
MAC Destination Address 6 Bytes
MAC Source Address 6 Bytes
MAC Type (or Length) 2 Bytes
Payload (Network PDU) 46 Bytes
Check Sequence (CRC) 4 Bytes
Total Frame Physical Size 84 Bytes

The maximum number of frames per second is:

Ethernet Data Rate (bits per second) / Total Frame Physical Size (bits)
    = 10 000 0000 / (84 x 8)
    = 14 880 frames per second.

Largest size of Ethernet frame

The maximum frame payload is 1500 Bytes, this will offer the highest throughput, when the frames are transmitted by only one node on the network (i.e. there are no collisions) To calculate the throughput provided by the link layer, one must first calculate the maximum frame rate for this size of frame.

Ethernet frame parts
Frame Part Maximum Size Frame
Inter Frame Gap (9.6µs) 12 Bytes
MAC Preamble (+ SFD) 8 Bytes
MAC Destination Address 6 Bytes
MAC Source Address 6 Bytes
MAC Type (or Length) 2 Bytes
Payload (Network PDU) 1500 Bytes
Check Sequence (CRC) 4 Bytes
Total Frame Physical Size 1538 Bytes

The largest frame consists of 1526 Bytes (see table above) with a 9.6 µs inter-frame gap (corresponding to 12 Bytes at 10 Mbps). The total utilised period (measured in bits) therefore corresponds to 1538 Bytes.

The maximum frame rate is:

Ethernet Data Rate (bits per second) / Total Frame Physical Size (bits)
    = 812.74 frames per second

The link layer throughput (i.e. number of payload bits transferred per second) is:

Frame Rate x Size of Frame Payload (bits)
    = 812.74 x (1500 x 8)
    = 9 752 880 bps.

This represents a throughput efficiency of 97.5 %.

Maximum frame rates reference

Provided by Roger Beeman, Cisco Systems

Maximum frame rates reference
Size (bytes) Ethernet (pps) 16Mb Token Ring (pps) FDDI (pps)
64 14880 24691 152439
128 8445 13793 85616
256 4528 7326 45620
512 2349 3780 23585
768 1586 2547 15903
1024 1197 1921 11996
1280 961 1542 9630
1518 812 1302 8138

Maximum number of frames per second

Maximum number of frames per second
Speed (bits per second) Frames Per Second (fps) Frames Per Second (fps)
10 Mbps 14880 14.8 kfps
100 Mbps 148809 148 kfps
1 Gbps 1488095 1.48 mfps
10 Gbps 14880952 14.8 mfps
25 Gbps 37202380 37.2 mfps
40 Gbps 59523809 59.5 mfps
100 Gbps 148809523 148 mpfs
(speed in bits) / ((frame size)*8)

Example for minimum default ethernet packet:
    (speed in bits) / (84*8)

Ethernet cable categories frequency

Category Speed Max frequency
CAT 1 Carry only voice 1MHz
CAT 2 4Mbps 4MHz
CAT 3 10Mbps 16Mhz
CAT 4 16Mbps 20Mhz
CAT 5 100Mbps 100Mhz
CAT 5e 1000Mbps 100Mhz
CAT 6 1000Mbps 250MHz
CAT 7 10Gbps 600MHz
CAT 7a 10Gbps 1000Hz
CAT 8 25Gbps 2000Mhz


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