just how secure is ssh?

[Jaded JAaron77]

My university has taken to packet sniffing to keep tabs on what is done on their network. I've a computer off-campus that I can access via ssh and create a tunnel for VNC, I'm just curious how easily they could see through that. I guess what I'm asking is exactly how good is ssh's encryption. (strange I'm actually typing this on the remote computer via the aforementioned tunnel and it doesn't pass arrow keys, backspace, or return)

[Ex-Cyber]

Assuming that your implementation is sound, I don't think it's feasible for them to actually break the encryption. However, they can still tell that you're connected to the other end of the tunnel, and may be able to perform traffic analysis to guess at the sorts of applications that you're running over the tunnel. Also, depending on your network configuration, it's possible that you would pass DNS queries over an unencrypted connection rather than the encrypted tunnel, which could basically tell them what sites you're talking to even though they wouldn't be able to see the actual connections.

[curt_grymala]

It depends on what you're connecting to. If you're connecting to the university network, and performing all of your actions there, they can basically see everything you're doing.

The communication between your computer and their network is encrypted and pretty safe from anyone hacking in between. However, on either end of the connection, everything is pretty much open.

It's the same concept as sending and receiving encrypted e-mail messages. The sender can see the message in plain text. The recipient can see the message in plain text. It's just encrypted for people trying to intercept it in between.

[Ex-Cyber]

Maybe I misunderstood, but I thought he was on university ethernet (e.g. resnet) and wanted to tunnel outside the university for privacy, not tunneling into the university network from some external ISP.

[Jaded JAaron77]

you're right, Ex, i'm on the university network, connecting to a computer off-campus.

so basically they'll be able to see who I'm connected to and that i'm using ssh/scp or maybe vnc over an ssh tunnel, but won't necessarily be able to see what files i'm transferring or what commands i'm sending over vnc?

[curt_grymala]

you're right, Ex, i'm on the university network, connecting to a computer off-campus.

so basically they'll be able to see who I'm connected to and that i'm using ssh/scp or maybe vnc over an ssh tunnel, but won't necessarily be able to see what files i'm transferring or what commands i'm sending over vnc?

Sorry. I misunderstood. It sounded to me like you were in an off-campus location trying to tunnel into the university network.

[BlackAura]

so basically they'll be able to see who I'm connected to and that i'm using ssh/scp or maybe vnc over an ssh tunnel, but won't necessarily be able to see what files i'm transferring or what commands i'm sending over vnc?

Yep. The actual data will all be encrypted, which includes everything sent or received after the connection is made. They'll be able to see an SSH connection with some kind of data traveling through it, and they'll be able to tell the IP addresses at either end of the connection, but that's about it.