A TLS Bicycle Attack refers to a method of discovering password length on encrypted packets transmitted via SSL, or HTTPS. The term was first coined on December 30, 2015, by Guido Vranken, who wrote: "The name TLS Bicycle Attack was chosen because of the conceptual similarity between how encryption hides content and gift wrapping hides physical objects. My attack relies heavily on the property of stream-based ciphers in TLS that the size of TLS application data payloads is directly known to the attacker and this inadvertently reveals information about the plaintext size; similar to how a draped or gift-wrapped bicycle is still identifiable as a bicycle, because cloaking it like that retains the underlying shape. The reason that I've named this attack at all is only to make referring to it