de-peering for security sake

Owen DeLong owen at
Sat Dec 26 23:11:13 UTC 2015

> On Dec 26, 2015, at 12:50 , Matthew Petach <mpetach at> wrote:
> On Sat, Dec 26, 2015 at 12:34 PM, Owen DeLong <owen at <mailto:owen at>> wrote:
>>> On Dec 26, 2015, at 08:14 , Joe Abley <jabley at> wrote:
>>> On Dec 26, 2015, at 10:09, Stephen Satchell <list at> wrote
>>>> My gauge is volume of obnoxious traffic.  When I get lots of SSH probes from a /32, I block the /32.
> [...]
>>> With respect to ssh scans in particular -- disable all forms of
>>> password authentication and insist upon public key authentication
>>> instead. If the password scan log lines still upset you, stop logging
>>> them.
>> This isn’t a bad idea, per se, but it’s not always possible for the guy running the server
>> to dictate usage to the people using the accounts.
>> Also, note that the only difference between a good long passphrase and a private key is,
>> uh, wait, um, come to think of it, really not much.
>> The primary difference is that nobody expects to have to remember a private key so we don’t
>> get fussed when they contain lots of entropy. Users aren’t good at choosing good long secure
>> passphrases and the automated mechanisms that attempt to enforce strong passwords just
>> serve to increase user confusion and actually reduce the entropy in passwords overall.
> No, the difference is that a passphrase works
> in conjunction with the private key, which is
> the "something you have" vs the "something
> you know" in two-factor authentication.

No… You are missing the point. Guessing a private key is roughly equivalent to guessing a really long
pass phrase. There is no way that the server side can enforce password protection of the private key
on the client side, so if you are assuming that public-key authentication is two-factor, then you are
failing miserably.

> With password authentication, there's only a
> single solution space for the attacker to
> sift through; with private key authentication,
> unless you're sloppy about securing your
> private key, there's two massive solution spaces
> for the attacker to sift through to find the unique
> point of intersection.

The point here is that securing the private key is a user task and not under the control of the administrator.
As such, you have to assume sloppy.

> Massively different solution space volumes
> to deal with.  Equating the two only has meaning
> in cosmological contexts.

Or contexts where the user is sloppy about securing their private key, e.g. the real world.


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