Re: Length of pre-shared key

[James Tiller <tiller@lucent.com>]

Juha -

I'm going out on a limb here... but technically there is no limit
since the key is only used locally in the creation of the SKEYID.
The real limit is in the PRF inputs, i.e. SKEYID =
prf(pre-shared-key, Ni_b | Nr_b)

Seeing that the Nonce can be between 8 and 256 bytes, it *could*
be logically surmised that the shared secret would have the same
consideration based on the PRF - but this depends on the process
implemented and supported.

Just my $0.02

-------------
Best regards,
Jim Tiller, CISSP
Global Security Product Manager
Lucent Worldwide Services
--
tiller@lucent.com
10:58 AM - 2/25/2002


Monday, February 25, 2002, 9:41:20 AM, juha wrote:
ollila>         Hello!

ollila> Have IPsec and IKE specifications any requirements about the pre-shared keys? I didn't find the required length of pre-shared key.

ollila> Best Regards,
ollila> Juha Ollila