Thus spake Sriram, Kotikalapudi (Fed) via NANOG (nanog@lists.nanog.org) on Tue, Aug 19, 2025 at 04:34:18PM +0000:
Question: Can a prefix be never routed on the Internet but used only one-way for source address in IP packets?
That is. a user owns an IP prefix. They never advertise a route to it in BGP on the Internet. But they use the prefix solely for source address in IP traffic from a source to a destination (sink). In this set up, the destination server obviously cannot/doesn't return any acknowledgements etc. to the source. Anyone aware if there is any such known application in use on the Internet - even if it is rare? Thanks.
We see this for example in a generalized pattern like instrument -> DAQ system -> UDP firehose -> FPGAs -> compute, which is a completely unidirectional application workflow. Dale