For bulk encryption, I'd suggest arcfour. The standardized form has issues with weak keys; it helps to throw away the start of the stream. There are @putty.projects.tartarus.org algorithms that throw away the first 1536 bytes (arcfour128-draft-00 at putty.projects.tartarus.org, which takes 16 bytes of key, and arcfour256-draft-00 at putty.projects.tartarus.org, which takes 32); I also have arcfour-64k at rodents.montreal.qc.ca, which throws away the first 64K. For the expensive crypto, there's not much to be done except be sure to implement (or use an implementation which implements) connection sharing. (Well, unless you have crypto accelerator hardware, I suppose, which is unlikely on a PDP-11.) For code size, the best thing I can think of is to compile it to a very-CISC instruction set, probably more CISCy than any real machine, then build an emulator for that. You'll pay a speed price, but slow-and-working is better than fast-but-won't-fit, and even the emulator is probably faster than overlays. You might even want to write it in a compact interpreted language. My own implementation, compiled for SPARC32, has sizes text=1118216 data=13248 bss=316060, which is much too large as it stands; I must admit some uncertainty whether even an emulated machine would fit. Perhaps two layers of emulation? Mouse

On Thu, 8 May 2014, John Willis wrote: It's not too snappy on a VAX 4000/300. I have Process Software's TCPware installed on mine - the initial negotiation takes 1-1/2 minutes, but after that is reasonably responsive. I don't recall the key length or encryption. Mike Loewen mloewen at cpumagic.scol.pa.us Old Technology http://sturgeon.css.psu.edu/~mloewen/Oldtech/

May I suggest using a openwrt router for the job. ssh to the router and open a telnet port on a separate utp port. [x] Done On 08-05-14 15:25, John Willis wrote: -- Met vriendelijke Groet, Simon Claessen drukknop.nl

It looks like this will be the way to go. Given the (relatively) huge memory footprint for the crypto, and the sheer amount of computation required, the pdp11 just isn't up to the job.