Paced and Packet-Pair TCP patches.

Enclosed you will find a patchfile and four new source files.
Apply the patches to FreeBSD 4.1 kernel source.
Add the files to the sys/netinet directory.
Pacing is compiled by adding

options	TCP_PACING

configuration file.  Packet-pair estimation is enabled by
also adding

options	TCP_CE

to the kernel configuration file.  TCP_CE requires
TCP_PACING.

The kernel configuration file also needs

options	HZ=1000

in the configuration file to support finer-grained timers.
This option often causes the wall-clock time to be incorrect;
using 512 instead of 1000 corrects this, but you lose precision.
It is not yet clear how much precision you really need.

There is also a SACK implementation here; it is enabled by
adding

options	TCP_SACK

to the configuration file.

After any change to the configuration file, run config on it,
then change to the build directory and

	make clean && make depend
	make