r7056@Kushana: nickm | 2006-08-08 23:40:53 -0700

   additional fields to existing structures; implementations are constrained

   to ignore fields they do not expect.

   Parties negotiate OR connection versions as described below in section

   Parties negotiate OR connection versions as described below in sections

   4.1 and 4.2.

2. Connections

   0 when the other side is recognized as a router running version

   0.1.2.??-alpha or earlier.

   If a server finds that it wants to send a cell (for example because a

   [If a server finds that it wants to send a cell (for example because a

   circuit wants to extend to that client, and the TLS connection

   is already established) yet no cell has arrived yet, we can't

   distinguish between a version 0 client and a slow network. We can't

   assume that the other side approves of version 0, so we can't just

   start using version 0. Perhaps the right answer is to then launch a

   new TLS connection because you don't have a usable one after all?

   new TLS connection because you don't have a usable one after all? -RD]

   [That would seem to be thrashy.  Let's see if we can do better.  Remember,

   normal v0 clients always send something after connecting, so if we have

   had a connection for a while and gotten nothing over it, we could get away

   with assuming it's bad.  Alternatively, we could identify V0 clients by

   the OU=Tor field in the certificates: we don't check for it, and we never

   documented it.  We might break other people's clients by sending them

   hello cells, but only if those clients are nonconformant.  Am I right?

   In any case, this seems way more reliable.  -NM]

5. Circuit management