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