“…Specific topics covered include: Block and stream symmetric ciphers, such as AES and RC4; and asymmetric ciphers, such as RSA and EIGamal Message authentication codes, including HMACs Tunneling technologies based on gtunnel SSL protocol for building network-to-network VPNs SSH protocols as drop-in replacements for telnet, ftp, and the BSD r-commands Lightweight VPNs, including VTun, CIPE, tinc, and OpenVPN IPsec, including its Authentication Header (AH) protocol, Encapsulating Security Payload (ESP), and IKE (the key management protocol) Packed with details, the text can be used as a handbook describing the functions of the protocols and the message formats that they use. …”