Disclosed are methods and systems for frustrating statistical attacks. A sender and receiver agree upon an encryption and integrity encoding scheme. For each "real" data packet, the sender generates integrity information, puts it in the packet, and then encrypts the packet using the agreed-upon scheme. Every now and again, the sender generates a "pseudo-data" packet encoded using a scheme different from the agreed-upon scheme. When the real-data and pseudo-data packets arrive at the receiver, they are decrypted using the agreed-upon scheme, and their validity is verified using the integrity information. Verification succeeds for real-data packets, and their data are accepted as valid. Verification fails for pseudo-data packets, however, and their data are discarded. An eavesdropper cannot differentiate pseudo-data from real-data and so cannot help but use all of the packets in its analysis. This mingling of pseudo-data with real-data frustrates the eavesdropper's statistical attempt to uncover the agreed-upon encoding scheme.