Re: [Emu] review of draft-ietf-emu-eaptunnel-req-04

["Dan Harkins" <[e-mail]>]

  Since they both use the same low-entropy password to perform their
mutual authentication it is not, strictly speaking, just the peer's
credential.

  Dan.

On Wed, March 3, 2010 1:45 pm, Hoeper Katrin-QWKN37 wrote:
>
> See inline.
>> -----Original Message-----
>> From: Dan Harkins [mailto:[e-mail]]
>> Sent: Wednesday, March 03, 2010 3:39 PM
>> To: Hoeper Katrin-QWKN37
>> Cc: Dan Harkins; Joseph Salowey; [e-mail]
>> Subject: RE: [Emu] review of draft-ietf-emu-eaptunnel-req-04
>>
>>
>>   Hi Katrin,
>>
>> On Wed, March 3, 2010 12:31 pm, Hoeper Katrin-QWKN37 wrote:
>> > Dan,
>> >
>> > OK, I understand that the tunnel provides all these other feats.
>> >
>> > But why can't the server authenticate during the tunnel protocol? I
>> > still don't understand the use case for mutually anonymous tunnels.
>>
>>   Because it doesn't have the right credential.
>>
>> > If the server has a certificate why can't it send it to the peer
> before
>> > or during the tunnel establishment?
>>
>>   If the server has a certificate then sending it to the peer
>> would not really solve any problem. The peer would still need to
>> have a reason to trust it and we're back to the problem of putting
>> a trusted certificate in some certificate store. A global PKI to
>> solve all of our certificate issues still has not materialized.
>>
>> > If the peer and server share a secret, than this could be used to
>> > establish the tunnel.
>>
>>   If the peer and server share a secret they could use one of the PSK
>> ciphersuites for TLS but those are susceptible to a dictionary attack
>> and are therefore inappropriate.
>>
>>   The tunnel is being established with EAP-TLS so we are limited to
>> TLS ciphersuites and the authentication they provide. If a TLS
> ciphersuite
>> was appropriate always and everywhere then we would not need any other
>> EAP methods, we'd just do EAP-TLS. But that is not the case. Also it
> is
>> a requirement to tunnel additional EAP methods inside the tunnel so
>> obviously there are EAP methods that provide something that a TLS
>> ciphersuite does not.
>>
>> > What I am saying is what kind of server authentication credentials
> could
>> > be used inside an anonymous tunnel that could not be used to
>> > authenticate the server in the tunnel protocol? (given that privacy
> is
>> > not the issue)
>>
>>   A low-entropy password that can easily be remembered and entered by
> a
>> human with low probability of error.
> [KH] I asked what kind of SERVER credentials not peer credentials.
>>
>>   Dan.
>>
>
>