113 lines
5.8 KiB
Text
113 lines
5.8 KiB
Text
|
|
More number for the questions about SSL overheads....
|
|
|
|
The following numbers were generated on a pentium pro 200, running linux.
|
|
They give an indication of the SSL protocol and encryption overheads.
|
|
|
|
The program that generated them is an unreleased version of ssl/ssltest.c
|
|
which is the SSLeay ssl protocol testing program. It is a single process that
|
|
talks both sides of the SSL protocol via a non-blocking memory buffer
|
|
interface.
|
|
|
|
How do I read this? The protocol and cipher are reasonable obvious.
|
|
The next number is the number of connections being made. The next is the
|
|
number of bytes exchanged bewteen the client and server side of the protocol.
|
|
This is the number of bytes that the client sends to the server, and then
|
|
the server sends back. Because this is all happening in one process,
|
|
the data is being encrypted, decrypted, encrypted and then decrypted again.
|
|
It is a round trip of that many bytes. Because the one process performs
|
|
both the client and server sides of the protocol and it sends this many bytes
|
|
each direction, multiply this number by 4 to generate the number
|
|
of bytes encrypted/decrypted/MACed. The first time value is how many seconds
|
|
elapsed doing a full SSL handshake, the second is the cost of one
|
|
full handshake and the rest being session-id reuse.
|
|
|
|
SSLv2 RC4-MD5 1000 x 1 12.83s 0.70s
|
|
SSLv3 NULL-MD5 1000 x 1 14.35s 1.47s
|
|
SSLv3 RC4-MD5 1000 x 1 14.46s 1.56s
|
|
SSLv3 RC4-MD5 1000 x 1 51.93s 1.62s 1024bit RSA
|
|
SSLv3 RC4-SHA 1000 x 1 14.61s 1.83s
|
|
SSLv3 DES-CBC-SHA 1000 x 1 14.70s 1.89s
|
|
SSLv3 DES-CBC3-SHA 1000 x 1 15.16s 2.16s
|
|
|
|
SSLv2 RC4-MD5 1000 x 1024 13.72s 1.27s
|
|
SSLv3 NULL-MD5 1000 x 1024 14.79s 1.92s
|
|
SSLv3 RC4-MD5 1000 x 1024 52.58s 2.29s 1024bit RSA
|
|
SSLv3 RC4-SHA 1000 x 1024 15.39s 2.67s
|
|
SSLv3 DES-CBC-SHA 1000 x 1024 16.45s 3.55s
|
|
SSLv3 DES-CBC3-SHA 1000 x 1024 18.21s 5.38s
|
|
|
|
SSLv2 RC4-MD5 1000 x 10240 18.97s 6.52s
|
|
SSLv3 NULL-MD5 1000 x 10240 17.79s 5.11s
|
|
SSLv3 RC4-MD5 1000 x 10240 20.25s 7.90s
|
|
SSLv3 RC4-MD5 1000 x 10240 58.26s 8.08s 1024bit RSA
|
|
SSLv3 RC4-SHA 1000 x 10240 22.96s 11.44s
|
|
SSLv3 DES-CBC-SHA 1000 x 10240 30.65s 18.41s
|
|
SSLv3 DES-CBC3-SHA 1000 x 10240 47.04s 34.53s
|
|
|
|
SSLv2 RC4-MD5 1000 x 102400 70.22s 57.74s
|
|
SSLv3 NULL-MD5 1000 x 102400 43.73s 31.03s
|
|
SSLv3 RC4-MD5 1000 x 102400 71.32s 58.83s
|
|
SSLv3 RC4-MD5 1000 x 102400 109.66s 59.20s 1024bit RSA
|
|
SSLv3 RC4-SHA 1000 x 102400 95.88s 82.21s
|
|
SSLv3 DES-CBC-SHA 1000 x 102400 173.22s 160.55s
|
|
SSLv3 DES-CBC3-SHA 1000 x 102400 336.61s 323.82s
|
|
|
|
What does this all mean? Well for a server, with no session-id reuse, with
|
|
a transfer size of 10240 bytes, using RC4-MD5 and a 512bit server key,
|
|
a pentium pro 200 running linux can handle the SSLv3 protocol overheads of
|
|
about 49 connections a second. Reality will be quite different :-).
|
|
|
|
Remeber the first number is 1000 full ssl handshakes, the second is
|
|
1 full and 999 with session-id reuse. The RSA overheads for each exchange
|
|
would be one public and one private operation, but the protocol/MAC/cipher
|
|
cost would be quite similar in both the client and server.
|
|
|
|
eric (adding numbers to speculation)
|
|
|
|
--- Appendix ---
|
|
- The time measured is user time but these number a very rough.
|
|
- Remember this is the cost of both client and server sides of the protocol.
|
|
- The TCP/kernal overhead of connection establishment is normally the
|
|
killer in SSL. Often delays in the TCP protocol will make session-id
|
|
reuse look slower that new sessions, but this would not be the case on
|
|
a loaded server.
|
|
- The TCP round trip latencies, while slowing indervidual connections,
|
|
would have minimal impact on throughput.
|
|
- Instead of sending one 102400 byte buffer, one 8k buffer is sent until
|
|
- the required number of bytes are processed.
|
|
- The SSLv3 connections were actually SSLv2 compatable SSLv3 headers.
|
|
- A 512bit server key was being used except where noted.
|
|
- No server key verification was being performed on the client side of the
|
|
protocol. This would slow things down very little.
|
|
- The library being used is SSLeay 0.8.x.
|
|
- The normal mesauring system was commands of the form
|
|
time ./ssltest -num 1000 -bytes 102400 -cipher DES-CBC-SHA -reuse
|
|
This modified version of ssltest should be in the next public release of
|
|
SSLeay.
|
|
|
|
The general cipher performace number for this platform are
|
|
|
|
SSLeay 0.8.2a 04-Sep-1997
|
|
built on Fri Sep 5 17:37:05 EST 1997
|
|
options:bn(64,32) md2(int) rc4(idx,int) des(ptr,risc1,16,long) idea(int) blowfish(ptr2)
|
|
C flags:gcc -DL_ENDIAN -DTERMIO -O3 -fomit-frame-pointer -m486 -Wall -Wuninitialized
|
|
The 'numbers' are in 1000s of bytes per second processed.
|
|
type 8 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes
|
|
md2 131.02k 368.41k 500.57k 549.21k 566.09k
|
|
mdc2 535.60k 589.10k 595.88k 595.97k 594.54k
|
|
md5 1801.53k 9674.77k 17484.03k 21849.43k 23592.96k
|
|
sha 1261.63k 5533.25k 9285.63k 11187.88k 11913.90k
|
|
sha1 1103.13k 4782.53k 7933.78k 9472.34k 10070.70k
|
|
rc4 10722.53k 14443.93k 15215.79k 15299.24k 15219.59k
|
|
des cbc 3286.57k 3827.73k 3913.39k 3931.82k 3926.70k
|
|
des ede3 1443.50k 1549.08k 1561.17k 1566.38k 1564.67k
|
|
idea cbc 2203.64k 2508.16k 2538.33k 2543.62k 2547.71k
|
|
rc2 cbc 1430.94k 1511.59k 1524.82k 1527.13k 1523.33k
|
|
blowfish cbc 4716.07k 5965.82k 6190.17k 6243.67k 6234.11k
|
|
sign verify
|
|
rsa 512 bits 0.0100s 0.0011s
|
|
rsa 1024 bits 0.0451s 0.0012s
|
|
rsa 2048 bits 0.2605s 0.0086s
|
|
rsa 4096 bits 1.6883s 0.0302s
|
|
|