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A Few Random Thoughts...




   Hi all,

As one of those lucky souls with access to almost limitless bandwidth and the skills (or stupidity) to use it, I suppose an apology is in order:

I'm sorry- after reviewing what *could* be the consequences, I have to whimp out based on professional risk factors... I can't run an exit node. So I have to leave it to other folks who have a different situation to do the heavy lifting.

What I *am* doing is deploying a couple of heavy iron closed relays on OC3 or better bandwidth. The first is now deployed after a lot of up and down testing, and I'll get to the second in due time.

I've been watching Tor for a long time and just recently decided to get involved. The Iran situation cemented that decision.

   Anyhow, here are some random thoughts:

On the "Who uses Tor?" section of the website, I see no mention of IT people. I've used the Tor network for many practical uses as an IT Director. These range from bypassing my own firewall to test incoming connections, to helping my legal department do research on a pending lawsuit without the opposition *knowing* we even looked at their website. Having a random and easily accessible IP to initiate connections from is a priceless testing tool. Especially when dealing with niggling routing problems.

On one occasion my ISP was having routing/DNS problems, and Tor was able to find an entrance node and allow me to work even though I couldn't get to my remote servers directly. This saved my client a lot of downtime, and might have saved me the account. Also, my employer's R&D department sometimes needs to look at things they don't want anyone to know they looked at (All quite legal mind you).

Quite frankly Tor is an undervalued IT tool and it's capabilities should be trumpeted loudly on the web page. You might also find IT guys like me throwing up some relays in exchange. After all- who has the bandwidth anyway?

And before anyone accuses me of it, I'm not nearly stupid enough to do a port scan over Tor. Phew.

One of the issues I ran into when looking into running an exit relay had to do with not only the legalities, but identifying a server vendor that was offshore from my home country and friendly to a Tor exit. In order for me to run an exit node, I have to be completely shielded.

As it stands now, I can probably run an exit for instant messaging- and that's it. However, if Tor itself had a relationship with someone who rents hardware, perhaps a partnership, Tor could get the exit nodes it needs, and the server vendor could get lots of cash. From my standpoint, it doesn't matter whether I rent or colocate my hardware. So if Tor as an organization had a partnership with a few server rental whores (in multiple countries), it would simplify getting more exits. I need servers, Tor runs with little impact on my server, I could care less where my remote hardware is provisioned from. Bingo- more exits.

I read back about 6 months in the or-talk list and there were a couple of suggestions inferring that *everyone* should be forced to be an exit node. I think this is a very bad idea, and hurts the security of the person trying to remain anonymous by causing an identifiable change in bandwidth usage that could infer Tor usage (Information leakage).

Simply speaking, on a default Windows/Vidalia installation, outgoing Tor traffic usually looks like https traffic, but on a forced exit, now Tor is identified by relatively matched traffic on port 443 both in and out of the client's connection (Unless it's entrance node is a *nix variant). This could mean death (literal) for a political dissident who is now identified as having an in/out matching traffic pattern assuming his entrance node is on Windows. It is more likely, that a country monitoring it's citizens would miss simple https traffic. But even myself as a lowly IT director, would have alarm bells going off if https was initiating in two directions from the same machine. Alternative ports can also set off alarm bells. But given the nature of Onion Routing, two way traffic needs to be avoided in the most sensitive sensitive situations. Forcing exit nodes is a bad idea for users. It will also drive away anyone who cannot provide an exit node.... that's chasing away bandwidth as non exit relays run for the hills.

   Long post. Too much coffee and too much time staring at routing tables.

   Michael