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Homechoice: Optimising the connection

How can I test my connection speed?

Connection Speed Tests

Network conditions notwithstanding, a Homechoice connection is limited by the speed of the serial connection between PC and set-top-box to 115,200 baud (bits/second). To transmit one byte of data down this serial line requires 10 bits - one start bit, 8 bits of data and one stop bit. (Read this article for a detailed explanation.) Therefore the absolute maximum download rate you're going to see is 11,520 bytes/second. In theory you should be able to simultaneously upload at this same rate too.

The TCP/IP protocol encapsulates data in packets of up to 1492 bytes (assuming you have MTU set to 1492) each with a header of several bytes which translates to some additional (small) overhead and a corresponding further speed reduction.

For more accurate results, use the following links to test your download speed.
Since the test files consist of pseudorandom binary data, most compression algorithms will have no effect upon them - indeed, "gzip -9" produces a larger file than the original. If you use one of the Unix / Linux commands listed below you can download to /dev/null thereby eliminating any disk performance bottlenecks on your own machine from the test procedure. Windows users may be able to achieve similar results by first installing the Cygwin package and using wget from there.

1. http://www.randall.homechoice.co.uk/test/10Kb (should take approx. 1 second)
2. http://www.randall.homechoice.co.uk/test/100Kb (should take approx. 10 seconds)
3. http://www.randall.homechoice.co.uk/test/1Mb (should take approx. 1min 40 seconds)
4. http://www.randall.homechoice.co.uk/test/10Mb (should take approx. 16min 40seconds)

Usage example for fetch:

$ fetch -o /dev/null http://www.randall.homechoice.co.uk/test/100Kb
Receiving /dev/null (102400 bytes): 100%
102400 bytes transferred in 9.0 seconds (11.06 kBps)

Usage example for snarf:

$ snarf http://www.randall.homechoice.co.uk/test/100Kb /dev/null
http://www.randall.homechoice.co.uk/test/100Kb (100K)
/dev/null  [########################] 100K |   11.06K/s
102400 bytes transferred in 9.00 sec (11.06k/sec)

Usage example for wget:
NB/ the -O option is an uppercase O!

$ wget -O /dev/null http://www.randall.homechoice.co.uk/test/100Kb
--23:28:34--  http://www.randall.homechoice.co.uk/test/100Kb
           => `/dev/null'
Connecting to www.randall.homechoice.co.uk:80... connected!
HTTP request sent, awaiting response... 200 OK
Length: 102,400 [text/plain]

    0K -> .......... .......... .......... .......... .......... [ 50%]
   50K -> .......... .......... .......... .......... .......... [100%]
  100K ->                                                        [100%]

23:28:44 (11.12 KB/s) - `/dev/null' saved [102400/102400]