Lucky Green wrote:
Ian Grigg wrote:
Also, a lot of cryptosystems are put together by committees. SSH was originally put together by one guy. He did the lot. Allegedly, a fairly grotty protocol with a number of weakneses, but it was there and up and running. And SSH-2 is apparantly nice, elegant and easy to understand, now that it has been fixed up.
ssh2 is in essence a re-invention of what SSL did without having to use X.509 keys. This reinvention was, IMHO, largely the result of the limitations of the ssh1 design.
OK. Learning more every day :-)
(SSH is the only really successful net crypto system, IMHO, in that it actually went into its market and made a mark. It's the only cryptosystem that is as easy to use as its non-crypto competitor, telnet. It's the only one where people switch and never return.)
I trust that we can agree that the volume of traffic and number of transactions protected by SSL are orders of magnitude higher than those protected by SSH. As is the number of users of SSL. The overwhelming majority of which wouldn't know ssh from telnet. Nor would they know what to do at a shell prompt and therefore have no use for either ssh or telnet.
Indeed! Although I trust that we can also look at many different ways of measuring success. In order to *compare* success, like for like, we have to start with an understanding of the marketplace for each system, and assume that the marketplace for each application is its universe. I (arbitratrily) define the marketplace for SSL as browsing. (I.e., HTTP, as used between a browser and a webserver. The SSL protected part might be referred to as HTTPS. This of course ignores all the other users of the protocol.) There, we can show statistics that indicate that SSL has penetrated to something slightly less than 1% of servers. It would of course be interesting to see what the bandwidth figures are like, for example, but I wouldn't be surprised if they are also less than 1% (think about all those yahoo monsters that overflow your POTS). The fact that a user of SSL is neither aware nor capable of being protected by SSH is irrelevant, neither is a sysadmin concerned in his job with protecting his work with SSL. (Actually that's not true; there was an SSL terminal system for a while, as an adjunct to SSLeay, but that is a dead or dying protocol, rapidly replaced by SSH whenever the two entered competition. Which is a good thing, the SSL terminal was a nightmare to get going, due to its insistance on hand crafting certificates.).
Given that SSL use is orders of magnitude higher than that of SSH, with no change in sight, primarily due to SSL's ease-of-use, I am a bit puzzled by your assertion that ssh, not SSL, is the "only really successful net crypto system".
SSL's 1% penetration into the browsing market doesn't strike me as successful. If I was "selling SSL" as a business, I'd be looking at the other 99% and wondering why it's just sitting there, not being sold. As there are big expensive companies doing just that; then I guess they have tried. Have a look at the penetration reports on http://www.securityspace.com/ On the other hand, SSH, as a cryptosystem, as an application (think: replacement for telnet, not as competitor to the SSL protocol) penetrates its market very well. I have no more than anecdotal evidence for that, but any sysadmin knows that once they started using SSH, they would never go back to the alternate unless forced, kicking and screaming. It would be very interesting to find out what SSH v. telnet traffic looks like. That's what I mean by success. Within its market place, SSH rules. -- iang --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majordomo@metzdowd.com