Unanswered Question
Apr 14th, 2008

Hi All

I am new to multicasting concept and here is my requirement.

I have one application server which sends multicast packet in network and at other end the receiver is receiving the same packets as they belong to same subnet.

Now the requirement is to have Server on one subnet (my company premises) and client machines resides remotely (other premises), client and server both has only internet connection in between no any VPN.

As up to noe i was using local multicast addressing as i dont want my request to go out side my L3 device, but to full fill my recent requirement i have to forward Multicast packets to outside network (internet) and from there it has to reach group of client only.


1) Is that possible?

2) If yes, Do i have to purchase Global Multicast IP Address?

3) or Is only to have some configuratioin on my L3 device or have to configure L3 device at my clisnt end?

4) If not all above, what is would be the procedure to have multicast environment overthe internet?

Please let me know your experience and put your suggetion to get this resolved.

- Dhaval Tandel

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Harold Ritter Tue, 04/15/2008 - 11:21


1) Yes, it is possible. You would probably be best to just encapsulate the multicast traffic in a GRE tunnel. This way it would look as unicast traffic to the Internet.

2) No need for global mcast address if you use the approach recommended in answer # 1.

3) The GRE tunnel can be configured between the router adjacent to the multicast source and the router adjacent to the receivers, given that these routers have global Internet addresses (NAT would probably work too).


dhavaltandel Tue, 04/15/2008 - 23:24

Thanks a lot Hritter,

But actually in my case the client can be at different location so can not have static tunnel in between, this is like i have Multicas Application in my premises for demo so client may vary as far as the location is concern.

Can you add something on this?

- Dhaval Tandel

Harold Ritter Fri, 04/18/2008 - 07:34


Unfortunately, Multicast is not globally available on the Internet today. Even if it was, you would probably need to make modification at every customer site to get multicast from the Internet.

Running mcast over some sort of vpn connection might be the easiest way to get this working. The other way would be to connect unicast to the application if this is possible.



This Discussion