The document presents three schemes to prevent selective jamming attacks by hiding packet classification at the physical layer: 1) A strong hiding commitment scheme that uses symmetric encryption to commit a sender to a message. 2) A cryptographic puzzle hiding scheme that requires solving a puzzle to obtain the decryption key. 3) Hiding based on all-or-nothing transformations that pre-processes packets before transmission to prevent classification until all pseudo-messages are received and transformed. The schemes aim to transform selective jamming into random jamming and were shown to effectively mitigate network performance degradation from such attacks.