Themonk, the US average is
not 12mbits as you have indicated because that would be suggesting most everyone has a fiber connection.
"A megabit is a unit of information or computer storage, abbreviated Mbit (or Mb)."
"1 megabit = 10(to the power of
6) = 1,000,000 bits which is equal to 125,000 bytes or 125 kilobytes." Taken from:
http://en.wikipedia.org/wiki/Megabit
So 12 megabits would equal 125 kilobytes x 12 = 1,500 kilobytes
"North America's average is 4452 kb/s" taken from:
http://www.speedtest.net/
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How they invented the speeds
T1 and up is the terminology for digital, two-way transmission of voice, data, or video over a single highspeed circuit. The transmission rate is based on the bandwidth for one voice channel in digital form. This channel is called DS-0 and consists of 64 kbps of bandwidth.
By Time Division Multiplexing 24 DS-0 channels, T1 is formed. But there is more. To separate the different channels a framing bit is used. For framing 8000 bps are used.
T1 gives you 24 analog voice channels plus the framing rate. This makes the T1 speed: 24 x 64000 + 8000 = 1.544 Mbps. For the other T-versions an equal equasion is used ending everything up to the specs given in the table below.
Carrier Signal Level # of T1 signals # of Voice Channels Speed
T1 DS-1 1 24 1544 kbps
T1c DS-1c 2 48 3152 kbps
T2 DS-2 4 96 6312 kbps
T3 DS-3 28 672 44736 kbps
T4 DS-4 168 4032 274760 kbps
Taken from:
http://ckp.made-it.com/t1234.html
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