Re: [Cfrg] VMAC Internet-Draft Available

[David McGrew <[e-mail]>]

Hi Ted,

thanks for posting.  I have not had a chance to read over it in  
detail yet, but I look forward to that.

I do have a quick question, though.  What would change if the high  
level structure were modified to something like Tag = F_K2(H_K1(M))?   
As you probably guessed, the reason that I ask is that I believe that  
there are applications that would be interested in alternatives to  
HMAC, but which would prefer to use a MAC that does not require a  
sequence number.

David

On Apr 24, 2007, at 10:32 AM, Ted Krovetz wrote:

> A new Internet-Draft is available for VMAC. The draft and reference  
> code are available at
>
>   http://fastcrypto.org/vmac
>
> VMAC is a message authentication code that is extremely fast on 64- 
> bit little-endian machines, and pretty fast on other architectures.  
> The primary goals of VMAC are:
>
> * High speed on 64-bit architectures. The table below gives sample  
> performance on several architectures. The code that generated these  
> numbers is written in C with a small amount of inline assembly.  
> Optimizing for other architectures requires as little as writing  
> efficient 64-bit multiplication, 128-bit addition and 64-bit byte- 
> swapping routines.
>
>                                           64-bit Tags     128-bit Tags
>         Bits/Endian/Architecture         64  512   4K     64  512   4K
>     ---------------------------------+-----+----+-----+-----+----+----
>     64/LE/AMD Athlon 64 "Manchester" |  6.0  1.1  0.5 |  7.0  1.6  0.9
>     64/LE/Intel Core 2 "Merom"       |  5.9  1.2  0.6 |  6.9  1.7  1.1
>     64/BE/IBM PowerPC 970FX          | 10.1  2.5  1.6 | 11.4  3.8  3.0
>     32/LE/Intel Core 2 "Merom"       |  8.3  2.2  1.4 | 11.1  3.6  2.8
>     32/LE/Intel NetBurst "Nocona"    | 15.0  4.4  3.1 | 18.9  7.1  5.8
>     32/BE/Freescale PowerPC 7457     | 15.3  6.4  5.3 | 22.1 11.2 10.0
>     32/LE/Embedded ARM v5te core     | 39.9 13.1 10.1 | 53.6 22.9 19.8
>     ---------------------------------+-----+----+-----+-----+----+----
>     Table: Tag generation speed measured in CPU cycles per message
>     byte, for cache-resident messages of length 64, 512 and 4K bytes.
>     Architectures are listed as register-size/endianness/model.
>
> * Reduction of per-session memory requirement over UMAC (A VMAC  
> predecessor). Whereas UMAC required 1080 bytes of internal key to  
> produce 64-bit authentication tags, VMAC uses 160 bytes. (If one  
> were to increase VMAC's internal key to the same as UMAC's, peak  
> speeds would be as low as 0.3 CPU cycles per byte.)
>
> * Retention of the virtues of UMAC: no intellectual-property  
> claims, provable security, flexibility between normal-security tags  
> (64-bit) and high-security tags (128-bit).
>
> VMAC was introduced at the Selected Areas of Cryptography 2006  
> conference. Special thanks go to Wei Dai, a very talented crypto  
> programmer. He read the SAC paper and then made significant  
> contributions to the VMAC design (increasing speed and security)  
> and code (resulting in the speeds reported here).
>
> A security note is being written and will be available on eCrypt  
> and the VMAC website later this summer. Any comments you may have  
> would be most welcome.
>
> Thank you,
> Ted Krovetz
> Computer Science Department
> California State University, Sacramento
>
>
> _______________________________________________
> Cfrg mailing list
> [e-mail]
> https://www1.ietf.org/mailman/listinfo/cfrg

_______________________________________________
Cfrg mailing list
[e-mail]
https://www1.ietf.org/mailman/listinfo/cfrg