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Re: Does this exist ?


From: Valdis.Kletnieks () vt edu
Date: Thu, 12 Jul 2007 14:03:54 -0400

On Thu, 12 Jul 2007 12:10:46 CDT, Dan Becker said:

There simply has to be a way to represent a larger value than you
transmit when you transmit.

Why does there "*have* to be" a way?  There's 32 bits available, that can
represent 2**32 different addresses.  You want to represent more than 2**32
addresses, you'll need more bits (see IPv6).

Note that it's possible to use some trickery to represent a larger *range*.
For example, TCP Window Scaling, where (basically) you send a TCP option that
says "Multiply all the windows by 8, or 16 or some other specified power-of-2".
The problem is that the number of different possible values doesn't change.
So for instance, the TCP window field in the header has 16 bits, so you can
represent 65536 different values 0, 1, 2, 3, 4,... 65534, 65535. WIth a window
scale of (say) 64, you can represent 0, 64, 128, 192, 255, ... 4194176,
4194240.  But there's still only 65536 different values - you can no longer
reresent 1-63, 65-127, and so on.

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