I currently use SSH Tunneling for all my DreamHost Email accounts pop+imap, which allows me to access email securely and without certificate security warnings.
The wiki article Tunneling over SSH in Windows explains how to do use putty for this, so I assume thats ok, maybe its not.
I also use Tunnels to perform automated backups and to sync files to different servers for DNS round robin load-balancing, also for backups using the backup user that came with my account, all of which use RSYNC+SSH.
I shouldn't think any of this would be disallowed, even running Firefox through an SSH Tunnel like you are asking about. They fine-tune both the bandwidth and the machine resources allowed by your user account and group on the server, so I'm not sure how this would cause any problems as they kill any user processes that hit their limits automatically.
I always understood that as being a process that is initiated on your server. Not forwarded like SSH Tunnels. I'm sure they wouldn't want you to create SSH Tunnels by setting up a cron script that runs ssh to allow for inbound connections, which would let you connect from anywhere at anytime as long as you had your authentication. By initiating the tunnel from our own machines when and only when we need it I don't see a problem.. But if your login information or private key is stolen that would allow a malicious entity to then do whatever they want, tunnelling their malicious traffic through DreamHost's servers which can cause them major grief.
I use (and recommend) DreamHost VPS though so maybe its totally different.
Would love to know I'm not endangering my account! Also would be nice to know DH helps those like msittig suffering from censorship.
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