I know RSA B-Safe stuff is made to fit onto cell phones and pagers. They also are the public key vendor for DOCSIS cable boxes. Maybe they can help you. www.rsa.com pz -----Original Message----- From: owner-cypherpunks@Algebra.COM [mailto:owner-cypherpunks@Algebra.COM]On Behalf Of Xiao, Peter Sent: Tuesday, January 09, 2001 10:13 PM To: 'Josh Richards'; coderpunks@toad.com; cypherpunks@toad.com Subject: RE: crypto implementation for small footprint devices -----Original Message----- From: Josh Richards [mailto:jrichard@cubicle.net] Sent: Tuesday, January 09, 2001 6:21 PM To: coderpunks@toad.com; cypherpunks@toad.com Subject: Re: crypto implementation for small footprint devices * Xiao, Peter [20010109 16:01]:

I am currently looking for crypto implementation that can fit into small footprint (in the order of 50K or less) devices. Ideally, an SSL type of protocol meets my requirements but it is almost impossible to implement it within 50K even with selected cipher suites. So, I am looking for alternatives (either symmetric key or public key based). I was thinking about WTLS but looks like its implementation can not be significantly smaller than that of TLS since it is also based on Public Key cryptography (I am wondering how it fits into a cellphone). Can any one tell me what is the approximate size of the client implementation of WTLS. Also, would anyone send some pointers to me regarding what I am looking for.

How small of footprint? 50K (presuming you mean in currency) isn't really a measurement of footprint size to me. :) Would something along the lines of a Java iButton URL:http://www.ibutton.com/ match your requirements? It truly depends on what you need the device to be capable of...and I don't just mean the crypto implementation but is this a device to be self-powered? How do you need to interface with it? Etc. The device is a DCT2000 set-top box with very limited footprint. Since the box needs to run a lot of other applications, 50K is the space that we would like to spend on the security purpose. The platform supports C interface. -jr ---- Josh Richards [JTR38/JR539-ARIN] Geek Research LLC - URL:http://www.geekresearch.com/ IP Network Engineering and Consulting

--On Wednesday, January 10, 2001 2:00 AM -0500 Declan McCullagh wrote:

It also might be worth checking out the elliptic curve apps that run on Palm OS. --Declan

Declan: A Canadian company, Certicom has been developping Elliptic curve crypto libraries for quite a while. Thier software is in many embedded devices and several PDA's including the palm. hope it's of help regards robert