can you tunnel multicast over secure shell?

Question

Level 5

4,155 points

can you tunnel multicast over secure shell?

Can multicast IP packets be tunneled over ssh? That is, can one
"ssh -L 5297:localhost:5297 -L 5298:localhost:5298 remote.cmptr.IP.addr"
and have that remote computer appear as if it is on the same local subnet (at least insofar as multicast traffic to those two ports is concerned)? Or is there some other novel way of doing it?

I have heard that multicast packets do traverse a VPN, but not sure if ssh will do this.

Thanx in advance!

2001 Quicksilver G4, Mac OS X (10.4.6)

Posted on May 7, 2006 10:00 PM

Reply

Answer 1

May 7, 2006 10:17 PM in response to j.v.

It should work, and as far as I can tell it does work. There are a couple of pages I found using Google that refer to tunnelling iTunes through ssh tunnels, with the note that the Bonjour multicast packets get through, so I don't think you'll have any problems.

Reply

Answer 2

j.v. Author

Level 5

4,155 points

May 8, 2006 7:09 PM in response to Michael Newbery

Actually, I am considering plunking out a few buck$ on two iSight cameras, in order to set up point-to-point AV comms. Most of the forum traffic in iChatAVland seems to be AIM/Jabber server related, or Mac-to-PC related. No questions about running iChatAV over ssh tunnels. I understand that one of the options with iChatAV is to communicate via Bonjour, which, if I have half a clue, is multicast IP technology. So, rather than leave a gazillion ports open on both DSL/cable modems at each end of the circuit, tunneling the iChatAV Bonjour ports over ssh would really be cool.

So you're from Wellington...as I recall, that's the capital, isn't it? On the southern end of the north island? Been a long time, going on ten years now, but toured NZ when I came off the Ice for the last time (was working for the US Antarctic Program at the time). Great country, really enjoyed my visit there.

Anyways, I'll be sure to let you know how this iSight/iChatAV/Bonjour/multicastIP over ssh stuff turns out...I'm feeling a bit more adventurous about gambling my money on a couple of iSights now...

Stay tuned!

Reply

Answer 3

May 9, 2006 5:58 PM in response to j.v.

I understand that one of the
options with iChatAV is to communicate via Bonjour,
which, if I have half a clue, is multicast IP
technology. So, rather than leave a gazillion ports
open on both DSL/cable modems at each end of the
circuit, tunneling the iChatAV Bonjour ports over ssh
would really be cool.

The announcement part of Bonjour is multicast, but the actual iChatAV traffic will just be straight unicast IP.

So you're from Wellington...as I recall, that's the
capital, isn't it? On the southern end of the north
island? Been a long time, going on ten years now, but
toured NZ when I came off the Ice for the last time
(was working for the US Antarctic Program at the
time). Great country, really enjoyed my visit there.

Your memory does not fail you. I'm pleased you liked the place. I'm rather fond of it myself 🙂
I'm afraid I've not made to to Colorado yet (flown over it I guess, but that hardly counts).

Looking forward to hearing your results...

Reply