Difference between revisions of "Bandwidth"

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[[Category:Engineering]]
 
[[Category:Engineering]]
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== 9600 baud is about a screen per second of text ==
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A 9600 "baud" connection is a little less than 1K per second. That's about 1 screen full of human text on an 80x24 terminal every second. ... Really, if every line was filled solid that's about one full screen every 2 seconds. Typical text for humans averages using only 1/2 the screen.
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== 16550 UART ==
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16550 UART chips can handle up to 115.2 kbit/s (115200 bps)
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== Bandwidth comparisons ==
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kbps = kbit/s = kbits per second = thousand bits per second
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MBps = MByte/s = MByte per second = megabytes per second
  
 
{| style="text-align:left;"
 
{| style="text-align:left;"
 
|-
 
|-
! align="left" | <big>Connection</big>
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! align="left" | '''Connection'''
! <big>Bit</big>
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! '''Bits per second'''
! <big>Bytes</big>
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! '''Bytes per second'''
! <big>Real World Expected Throughput</big>
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! '''Real World Expected Throughput'''
 
|-
 
|-
| TTY (V.18) || '''0.045 kbit/s''' || TTY uses a Baudot_code code, not ASCII. This uses 5 bits per character instead of 8, plus one start and 1.5 stop bits (7.5 total bits per character sent). || 6 characters/sec ||
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| TTY (V.18) || '''0.045 kbit/s''' || TTY uses a Baudot_code code, not ASCII. This uses 5 bits per character instead of 8, plus one start and 1.5 stop bits (7.5 total bits per character sent). || 6 characters per second ||
 
|-
 
|-
| Modem 300 (300 baud) (Bell 103 or V.21) || '''0.3 kbit/s''' || 0.03 kB/s (~30 cps) ||
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| Modem 300 (300 baud) (Bell 103 or V.21) || '''0.3 kbit/s''' || 0.03 kB/s (30 characters per second ~ about reading speed) ||
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|-
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| serial 9600 8N1 (close to V.32 9600 baud) || '''9.6 kbit/s'''<br />(10 bits per word) || 0.96 kB/s (960 Bytes/s) ||
 
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| Modem 56k (V.92) || '''56.0/48.0 kbit/s''' || 5.6/4.8 kB/s ||
 
| Modem 56k (V.92) || '''56.0/48.0 kbit/s''' || 5.6/4.8 kB/s ||
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|-
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| serial 57600 8N1 || '''57.6 kbit/s'''<br />(10 bits per word) || 5.76 kB/s (5760 Bytes/s) ||
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|-
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| serial 115200 8N1 || '''115.2 kbit/s'''<br />(10 bits per word) || 11.52 kB/s (11520 Bytes/s) ||
 
|-
 
|-
 
| DS1/T1 || '''1.544 Mbit/s''' || 0.192 MB/s ||
 
| DS1/T1 || '''1.544 Mbit/s''' || 0.192 MB/s ||
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| Gigabit Ethernet (1000base-X) || '''1000 Mbit/s''' || 125 MB/s || 600 Mbit/s (75 MB/s)
 
| Gigabit Ethernet (1000base-X) || '''1000 Mbit/s''' || 125 MB/s || 600 Mbit/s (75 MB/s)
 
|-
 
|-
| 802.11b DSSS 0.125|| '''11.0 Mbit/s''' || 1.375 MB/s ||
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| Bluetooth 2.0+EDR || '''3 Mbit/s''' || 0.375 MB/s ||
 
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|-
| 802.11a 0.75 || '''54.0 Mbit/s''' || 6.75 MB/s ||
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| 802.11b || '''11.0 Mbit/s''' || 1.375 MB/s ||
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|-
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| 802.11a || '''54.0 Mbit/s''' || 6.75 MB/s ||
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|-
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| 802.11g || '''54.0 Mbit/s''' || 6.75 MB/s ||
 
|-
 
|-
 
| 802.11n || '''248.0 Mbit/s''' || 31 MB/s ||
 
| 802.11n || '''248.0 Mbit/s''' || 31 MB/s ||
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|-
 
|-
 
| eSATA (SATA 300) || '''2400 Mbit/s''' || 300 MB/s ||
 
| eSATA (SATA 300) || '''2400 Mbit/s''' || 300 MB/s ||
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|-
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| USB 3.0 || '''4.80 Gbit/s''' || 600 MB/s ||
 
|-  
 
|-  
 
| PC2100 DDR-SDRAM (single channel) ||  '''16.8 Gbit/s''' || 2.1 GB/s ||
 
| PC2100 DDR-SDRAM (single channel) ||  '''16.8 Gbit/s''' || 2.1 GB/s ||

Latest revision as of 13:02, 18 May 2011


9600 baud is about a screen per second of text

A 9600 "baud" connection is a little less than 1K per second. That's about 1 screen full of human text on an 80x24 terminal every second. ... Really, if every line was filled solid that's about one full screen every 2 seconds. Typical text for humans averages using only 1/2 the screen.

16550 UART

16550 UART chips can handle up to 115.2 kbit/s (115200 bps)

Bandwidth comparisons

kbps = kbit/s = kbits per second = thousand bits per second

MBps = MByte/s = MByte per second = megabytes per second

Connection Bits per second Bytes per second Real World Expected Throughput
TTY (V.18) 0.045 kbit/s TTY uses a Baudot_code code, not ASCII. This uses 5 bits per character instead of 8, plus one start and 1.5 stop bits (7.5 total bits per character sent). 6 characters per second
Modem 300 (300 baud) (Bell 103 or V.21) 0.3 kbit/s 0.03 kB/s (30 characters per second ~ about reading speed)
serial 9600 8N1 (close to V.32 9600 baud) 9.6 kbit/s
(10 bits per word)
0.96 kB/s (960 Bytes/s)
Modem 56k (V.92) 56.0/48.0 kbit/s 5.6/4.8 kB/s
serial 57600 8N1 57.6 kbit/s
(10 bits per word)
5.76 kB/s (5760 Bytes/s)
serial 115200 8N1 115.2 kbit/s
(10 bits per word)
11.52 kB/s (11520 Bytes/s)
DS1/T1 1.544 Mbit/s 0.192 MB/s
T2 6.312 Mbit/s 0.789 MB/s
T3 44.736 Mbit/s 5.5925 MB/s
OC1 51.84 Mbit/s 6.48 MB/s
OC3 155.52 Mbit/s 19.44 MB/s
Ethernet (10base-X) 10 Mbit/s 1.25 MB/s 6 Mbit/s (0.75 MB/s)
Fast Ethernet (100base-X) 100 Mbit/s 12.5 MB/s 60 Mbit/s (7.50 MB/s)
Gigabit Ethernet (1000base-X) 1000 Mbit/s 125 MB/s 600 Mbit/s (75 MB/s)
Bluetooth 2.0+EDR 3 Mbit/s 0.375 MB/s
802.11b 11.0 Mbit/s 1.375 MB/s
802.11a 54.0 Mbit/s 6.75 MB/s
802.11g 54.0 Mbit/s 6.75 MB/s
802.11n 248.0 Mbit/s 31 MB/s
PCI 32-bit/33 MHz 1067 Mbit/s 133.33 MB/s
PCI 64-bit/100 MHz 6399 Mbit/s 800 MB/s
Serial ATA (SATA-150) 1500 Mbit/s 187.5 MB/s
Serial ATA (SATA-300) 3000 Mbit/s 375 MB/s
Serial Attached SCSI (SAS) 3000 Mbit/s 375 MB/s
RS-232 Serial max 0.2304 Mbit/s 0.0288 MB/s
USB 2.0 (USB Hi-Speed) 480 Mbit/s 60 MB/s
eSATA (SATA 300) 2400 Mbit/s 300 MB/s
USB 3.0 4.80 Gbit/s 600 MB/s
PC2100 DDR-SDRAM (single channel) 16.8 Gbit/s 2.1 GB/s
PC3200 DDR-SDRAM (single channel) 25.6 Gbit/s 3.2 GB/s
PC2100 DDR-SDRAM (dual channel) 33.6 Gbit/s 4.2 GB/s
PC3200 DDR-SDRAM (dual channel) 51.2 Gbit/s 6.4 GB/s