Internet Protocol Security (IPsec)

Internet Protocol Security, or IPsec, is a suite of protocols for securing communication at the IP layer. It provides confidentiality, integrity and authenticity for transmitted data packets. It uses the Encapsulating Security Payload protocol for encryption and the Authentication Header for integrity verification, complemented by Internet Key Exchange for key negotiation. IPsec operates in transport mode to secure individual connections or in tunnel mode, where the entire packet is encapsulated. Encryption methods such as AES are applied together with hash functions for checksum generation. The main application is VPN connectivity, for example site-to-site tunnels for connecting locations or remote access for mobile workplaces. IPsec is supported by firewalls, routers and VPN gateways from virtually all manufacturers.