I would like to know whether there is any open free radius server which supports radius fragmentation i.e. radius server which accepts packets greater than 4k size limit from the client and will do reassembly of the packet at server end. And once whole packet is assembled, will do the successful authentication of the packet?
Any pointers will help.
On
No, but there is an RFC currently in draft for this, instead of inventing your own scheme you should use the draft standard. When it's complete, we will add support to FreeRADIUS for packet fragmentation.
https://datatracker.ietf.org/doc/html/draft-perez-radext-radius-fragmentation-06
I'm not aware of any, and not sure if you could even do this. Since there is no nice header structure I can't guarantee packets will be "complete". When we have a "large" packet, we end up splitting it and using a VSA carrying an association value. For example, we have an interim record with a VSA(AssociationID)=00512121 and another with that same association ID. You could do a lot of black magic with CoA messages.