one embodiment of the present invention verifies the pacs before any processing of that packet is done this ensures that invalid data is never processed however recognizing that pac verification may slow down the packet processing which might not be suitable for certain classes of packets e g resolve packets an alternate embodiment of the present invention does not verify the pac in these packets in addition to pac verification the security infrastructure of the present invention also performs an id ownership check to validate the pac as discussed above identity theft can be discovered by simple validation of the address certificate before using that address in pnrp or other p2p protocols this validation may entail simply verifying that the id is the hash of the public key included in the certificate the ownership validation may also entail the issuance of an inquire packet to the address in that pac the inquire packet will contain the id to be verified and a transaction id if the id is present at that address the node should acknowledge that inquire if the id is not present at that address the node should not acknowledge that inquire if the certificate chain is required to verify the identity the node returns the complete certificate chain while signature and id gt url validation is still complex and a significant use of resources as is validating the chain of trust in a supplied cert chain the system of the present invention avoids any sort of challenge response protocol which would add an additional level of.