44 lines
2.0 KiB
HTML
44 lines
2.0 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
|
|
<HTML>
|
|
<HEAD>
|
|
<META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9">
|
|
<TITLE>Compressed TCP/IP-Sessions using SSH-like tools: Thoughts about performance.</TITLE>
|
|
<LINK HREF="Compressed-TCP-5.html" REL=next>
|
|
<LINK HREF="Compressed-TCP-3.html" REL=previous>
|
|
<LINK HREF="Compressed-TCP.html#toc4" REL=contents>
|
|
</HEAD>
|
|
<BODY>
|
|
<A HREF="Compressed-TCP-5.html">Next</A>
|
|
<A HREF="Compressed-TCP-3.html">Previous</A>
|
|
<A HREF="Compressed-TCP.html#toc4">Contents</A>
|
|
<HR>
|
|
<H2><A NAME="s4">4. Thoughts about performance.</A> </H2>
|
|
|
|
<P>Of course compression/encryption takes CPU time. It turned out that an
|
|
old Pentium-133 is able to encrypt and compress about 1GB/hour -- that's quite
|
|
a lot. If you compile SSH with the option "--with-none" you can
|
|
tell SSH to use no encryption. That saves a little performance. Here is a comprise
|
|
between several download methods (during the test, a noncompressed 6MB-file
|
|
was transfered from a 133MHz-Pentium-1 to a 233MHz Pentium2 laptop over a 10MBit
|
|
ethernet without other load).
|
|
<P>
|
|
<PRE>
|
|
+-------------------+--------+----------+-----------+----------------------+
|
|
| | FTP |encrypted |compressed |compressed & encrypted|
|
|
+-------------------+--------+----------+-----------+----------------------+
|
|
+-------------------+--------+----------+-----------+----------------------+
|
|
| Elapsed Time | |7.6s | 26s | 9s | 23s |
|
|
+-------------------+--------+----------+-----------+----------------------+
|
|
| Throughput | 790K/s | 232K/s | 320K/s | 264K/s |
|
|
+-------------------+--------+----------+-----------+----------------------+
|
|
|Compression Factor | 1 | 1 | 3.8 | 3.8 |
|
|
+-------------------+--------+----------+-----------+----------------------+
|
|
|
|
</PRE>
|
|
<HR>
|
|
<A HREF="Compressed-TCP-5.html">Next</A>
|
|
<A HREF="Compressed-TCP-3.html">Previous</A>
|
|
<A HREF="Compressed-TCP.html#toc4">Contents</A>
|
|
</BODY>
|
|
</HTML>
|