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New Member

UDP to TCP translation

Hi all,

we have a routing network based on cat 3550. Sensitive traffic and main transport protocol is udp. Everything is working.

Now we want to buil a backup network based on GPRS "modems". GPRS modems only route ip and tcp. They do not route udp.

So we have have to "translate" udp to tcp when communication is established bt GPRS net.

I have check about ip forwod-protocol interface commnad, but it seems is only oriented to udp broadcast packets (using also ip helper-address command).

Despite of routing methof (which is working), how can we transform udo in tcp?

Thx to all

  • LAN Switching and Routing

Re: UDP to TCP translation


If a device is capable of routing IP, then it is implicit that it will be able to transport any ip packets. It is not going to distinguish whether the payload inside the ip is actually TCP or not.

You have mentioned that GPRS modems will route ip. If they are capable of transporting IP packets, then it is evident that TCP/UDP packets will be transported by GPRS modems.

TCP/UDP are layer 4 protcols, where as IP is layer 3. So where is the problem.??

Please feel free to get back to us.


New Member

Re: UDP to TCP translation


the main thing is that GPRS network (provided by Vodafone)is doing a sort of tunneling that does not support UDP.

We can get much more infor since this is an information porvided by customer.

The choice of the backup network was done by customer, and its config is out of our responsability.

So the question is to know, if there is a method or a way to transform udo packets in tcp software, protocols tranformation or whatever.


Re: UDP to TCP translation


Thanks for reverting back.

We can tunnel those udp packets to traverse via GRE tunnel. Im not sure whether this will work in your scenario through your service provider, as you have mentioned that there are some restrictions.

The best suggestion would be to check with your service provider on possibilities for your scenario and whether GRE tunneling would help.

Hope this helps.


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