Re: small authenticator

At 12:10 PM 01/19/2000 -0700, [EMAIL PROTECTED] wrote: >Several people have suggested using a MAC; my problem is that the >opponent can reverse-engineer the chip and find the key. I was hoping >to give the chips a public key and have it encrypt a challenge that I'll >respond to. On my side, I'd

Re: small authenticator

7; heel of a vulnerable cleartext password database. Enzo - Original Message - From: Bill Stewart <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Thursday, January 20, 2000 4:37 Subject: Re: small authenticator > You don't have enough room

Re: small authenticator

You don't have enough room for RSA keys. I'd be surprised if you could fit elliptic-curve math into something that small, though there's enough room to store keys. Maybe the Certicom folks know more about it. For some kinds of authentication, a MAC is fine - you've got a server somewhere that kno

Re: small authenticator

At 11:13 AM -0600 1/19/2000, Rick Smith wrote: >At 04:49 PM 01/18/2000 -0700, [EMAIL PROTECTED] wrote: >>I've got something with around 100 bytes of ram and an 8-bit multiply. >>Is there an authentication mechanism that can fit in this? > >What types of attacks are you concerned with? That's the m

Re: small authenticator

Several people have suggested using a MAC; my problem is that the opponent can reverse-engineer the chip and find the key. I was hoping to give the chips a public key and have it encrypt a challenge that I'll respond to. On my side, I'd need to prevent chosen-cipehrtext attacks. -- Mike Stay Pr

Re: small authenticator

At 04:49 PM 01/18/2000 -0700, [EMAIL PROTECTED] wrote: >I've got something with around 100 bytes of ram and an 8-bit multiply. >Is there an authentication mechanism that can fit in this? What types of attacks are you concerned with? That's the main question. If you have a direct, unsniffable con

Re: small authenticator

[EMAIL PROTECTED] wrote: > > I've got something with around 100 bytes of ram and an 8-bit multiply. > Is there an authentication mechanism that can fit in this? HMAC? Cheers, Ben. -- SECURE HOSTING AT THE BUNKER! http://www.thebunker.net/hosting.htm http://www.apache-ssl.org/ben.html "My gr

small authenticator

I've got something with around 100 bytes of ram and an 8-bit multiply. Is there an authentication mechanism that can fit in this? -- Mike Stay Programmer / Crypto guy AccessData Corp. mailto:[EMAIL PROTECTED]