This book along with the essay "Beyond Cryptographic Routing: The Echo Protocol in the Era of Exponential Encryption" describe a new protocol: The Echo Protocol and its characteristics with respect to Graph-Theory, Routing-Theory, Networking and Encryption. As a contrast to the TCP protocol, the ECHO is a protocol without routing information. Instead, it's a multi- and hybrid-encryption concept. A network node sends packets to all connections. This creates the new network type of a flooding network, which is particularly interesting in the context of anonymizing mix networks like Tor or I2P and other. The modes of operation of the Echo Protocol like Full, Half or Adaptive Echo and sub-protocols of the Echo protocol like the POPTASTIC protocol (which is encrypted chat over e-mail servers) or the SECRED protocol (which is a kind of cryptographic discovery like in a DHT) complement further interesting innovations: Some Servers will learn someday through being instructed by private cryptog