STM0 STM1 STM4 STM16 STM64 STM256 capacity and speed

The page compares STM0 vs STM1 vs STM4 vs STM16 vs STM64 vs STM256 capacity and speed. It mentions difference between STM0, STM1, STM4, STM16, STM64 and STM256 with respect to capacity or speed.

CCITT has defined new multiplex hierarchy known as SDH (Synchronous Digital Hierarchy). The PDH and SDH hierarchies are used with digital multiplexers in exchanges. The different hierarchies having different bit rates are combined. STMs (Synchronous Transport Modules) are fiber optic network levels as defined in SDH for different bit rates. Refer PDH vs SDH >>

PCM E1 frame

The figure-1 depicts E1-frame. E1 frame takes 8 bits from each of the 64 kbps channels one by one. It retransmits these channels at 2048 kbps. E1 frame accomodates 30 voice channels including two additional 64 kbps channels. These two additional channels are used to transmit synchronization, service and signaling data. This results into E1 transmission rate of 2.048 Mbps or 2048 kbps equala to 32 * 64 kbps. E4 refers to 140 Mbps in the description below. Refer T1 frame vs E1 frame >>.

SDH uses basic digit rate of 155.52 Mbps and multiples of this by factors of 4*n. This basic SDH signal is called "d which include STM4, STM16, STM64 and STM256. Following paragraph mentions speed and capacity of these STM levels with respect to E1 and E4 as defined below.
➤E1 = 2.048 Mbps
➤E2 = 4 x E1 (8.448 Mbps)
➤E3 = 4 x E2 (34.368 Mbps)
➤E4 = 4 x E3 (139.264 Mbps)
➤E5 = 4 x E4 (565.148 Mbps)

STM0 Speed | STM0 Capacity

• STM0 : Synchronous transport module at level 0
• Speed (Bit Rate): 51.84 Mbits/sec
• Abbreviated bit rate: 51 Mbps
• capacity: 21 * E1

STM1 Speed | STM1 Capacity

• STM1 : Synchronous transport module at level 1
• Speed (Bit Rate): 155.52 Mbits/sec
• Abbreviated bit rate: 155 Mbps
• capacity: 63*E1 or 1*E4

STM4 Speed | STM4 Capacity

• Speed (Bit Rate): 622.08 Mbits/sec
• Abbreviated bit rate: 622 Mbps
• capacity: 252*E1 or 4*E4

STM16 Speed | STM16 Capacity

• Speed (Bit Rate): 2488.32 Mbits/sec
• Abbreviated bit rate: 2.4 Gbps
• capacity: 1008*E1 or 16*E4

STM64 Speed | STM64 Capacity

• Speed (Bit Rate): 9953.28 Mbits/sec
• Abbreviated bit rate: 10 Gbps
• capacity: 4032*E1 or 64*E4

STM256 Speed | STM256 Capacity

• Speed (Bit Rate): 39813.12 Mbits/sec
• Abbreviated bit rate: 40 Gbps
• capacity: 16128*E1 or 256*E4


Ethernet business    Ethernet over copper    Ethernet tutorial    DWDM system basics    Fibre optic communication    Types of WDM    PDH versus SDH    SONET versus SDH    What is PDMA?    What is WDM?    SONET SDH tutorial    SDH Networks    SDH Frame structure    SDH Modulation    PDH over SONET    PDH Frame structure

RF and Wireless Terminologies