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>Key continuity gets you pretty far, But that implies that some time in the past, you had a "first contact" with the real Paypal. You then need something some

by jasode 9y ago

>Key continuity gets you pretty far, But that implies that some time in the past, you had a "first contact" with the real Paypal. You then need something somewhere that helps validate that initial trust. And let's say a computer already made first contact with paypal.com and bankofamerica.com, what happens when the user needs to format the harddrive or gets a brand new smartphone? Do they export their previous successful handshakes to a flash card and import them into their new device to maintain key continuity? Or is it easier to use an entity (CAs or something similar) to help establish indentity+trust?

rocqua 9y ago
There is no either or. Key continuity combined with CAs is better than either alone. CAs for the first use, and key continuity for most of the rest. Another interesting option is called triangulation IIRC. The idea is to randomly query some other clients for their key-continuity info on first use.
- jasode 9y ago
  >There is no either or. Right, but it seemed like tedunangst's continuity suggestion was an answer to tptacek's "You cannot have privacy without some form of trust or identity." Since continuity doesn't work for 1st contact, it still doesn't solve the fundamental trust issue. Based on the thread's context about the value or worthlessness of CAs... If you have to still use CAs for 1% of the key handshakes, "key continuity" seems like a tangent to the topic.
  - tedunangst 9y ago
    I think we're veering into pedantic silliness, but "the person I talked to on Monday" is an identity. (Created on the fly when I speak with them on Monday.) This isn't always a useful identity, but perhaps a relevant point in a discussion of identity vs trust.
WorldMaker 9y ago
You've already established an implicit trust of the DNS at that point to even make that first trust with a paypal.com or bankofamerica.com. The various DNS-pinned certificate proposals aren't necessarily the right answer either, but the proponents are correct that the "first contact" with a server isn't with the server at all, but in DNS name resolution. If you trust DV certs at all, a lot of it is because you trust DNS, for the most part, and the DNS-pinning certificate advocates are at least correct that if we're all relying on that as our identity+trust database then they already are our most important CAs today in identity+trust discussions.
tracker1 9y ago
It would be easy enough to have a few "trusted" and "pinned" domains in the browser, or even certs... these pinned sites could then be used to do the cert lookup validation, which then runs against the SOA for the domain... There's ways to do third party validation of a DNS entry.. only so much that it's the correct entry, since that's really all DV gives you anyway with automation. This is really only needed on first contact too.

by jasode 9y ago

rocqua 9y ago

There is no either or. Key continuity combined with CAs is better than either alone. CAs for the first use, and key continuity for most of the rest. Another interesting option is called triangulation IIRC. The idea is to randomly query some other clients for their key-continuity info on first use.

jasode 9y ago
>There is no either or. Right, but it seemed like tedunangst's continuity suggestion was an answer to tptacek's "You cannot have privacy without some form of trust or identity." Since continuity doesn't work for 1st contact, it still doesn't solve the fundamental trust issue. Based on the thread's context about the value or worthlessness of CAs... If you have to still use CAs for 1% of the key handshakes, "key continuity" seems like a tangent to the topic.
- tedunangst 9y ago
  I think we're veering into pedantic silliness, but "the person I talked to on Monday" is an identity. (Created on the fly when I speak with them on Monday.) This isn't always a useful identity, but perhaps a relevant point in a discussion of identity vs trust.

WorldMaker 9y ago

You've already established an implicit trust of the DNS at that point to even make that first trust with a paypal.com or bankofamerica.com. The various DNS-pinned certificate proposals aren't necessarily the right answer either, but the proponents are correct that the "first contact" with a server isn't with the server at all, but in DNS name resolution. If you trust DV certs at all, a lot of it is because you trust DNS, for the most part, and the DNS-pinning certificate advocates are at least correct that if we're all relying on that as our identity+trust database then they already are our most important CAs today in identity+trust discussions.

tracker1 9y ago

It would be easy enough to have a few "trusted" and "pinned" domains in the browser, or even certs... these pinned sites could then be used to do the cert lookup validation, which then runs against the SOA for the domain... There's ways to do third party validation of a DNS entry.. only so much that it's the correct entry, since that's really all DV gives you anyway with automation. This is really only needed on first contact too.