IPsec

Internet Protocol Security (IPsec) is a protocol suite for securing Internet Protocol(IP) communications by authenticating and encrypting each IP packet of a communication session. IPsec includes protocols for establishing mutual authenticationbetween agents at the beginning of the session and negotiation of cryptographic keysto be used during the session. IPsec can be used in protecting data flows between a pair of hosts (host-to-host), between a pair of security gateways (network-to-network), or between a security gateway and a host (network-to-host).[1]


Internet Protocol security (IPsec) uses cryptographic security services to protect communications over Internet Protocol (IP) networks. IPsec supports network-level peer authentication, data origin authentication, data integrity, data confidentiality (encryption), and replay protection.


IPsec is an end-to-end security scheme operating in the Internet Layer of the Internet Protocol Suite, while some other Internet security systems in widespread use, such asTransport Layer Security (TLS) and Secure Shell (SSH), operate in the upper layers at the Application layer. Hence, only IPsec protects all application traffic over an IP network. Applications can be automatically secured by IPsec at the IP layer.


https://en.wikipedia.org/wiki/IPsec