General Comments.
There are still no definition on what constitutes best protection against 
monitoring i.e. what offers best, adequate or minimal protection against 
monitoring.  Give one of the goal is to move the internet to better protect 
against this kind of activity, we need to clarify which actions in this draft 
best enable that goal and not just providing basic interoperability.

Section 3.4 and 4.1 needs to be consolidated as there is a lot of overlap 
between the two sections.

I think it is good to provide rational behind the recommendations for various 
cipher sites, it leaves the reader with some interpretation between that and 
the actual cipher suites. It would be better to actually list the cipher suites 
in question to remove any scope for misinterpretation.

Also support for the SNI is missing from the draft. This is a mandatory for any 
application interacting with a service.

Specific comments.

Section 3.2 still treats SSL 3.0 differently to TLS 1.0. Why is it ok to fall 
back to TLS 1.0 but not SSL 3.0 if both offer the same security?

Section 3.4.
bullet 3.  Implementations MUST NOT negotiate cipher suites with an effective 
key length of less than 112
bullet 5   Implementations SHOULD prefer cipher suites with greater than 128 
bits of effective key length
bullet 6  Given the foregoing considerations, implementation of the following 
suites are recommended (in order of preference)

*         TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384

*         TLS_DHE_RSA_WITH_AES_256_GCM_SHA384

*         TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256

*         TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
Rational: In the preceding bullet we give preference to cipher with 256 bit key

Also client MUST send an ec_point_formats extension

3.5 public key lengths.
Public key algorithms based on integer factorization or discrete logarithms 
MUST use a public key size of at least 2048 bits.

4.1
Clients SHOULD include TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 as the first 
proposal to any server.
Rational: Section 3.4 bullet 5 says we give preference to ciphers stronger than 
128 bits.

Clients MUST include the "supported elliptic curve" extension

Trevor

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