SSL and TLS provide a generic channel security mechanism on top of TCP. This means that SSL and TLS are protocols that enable secure communication between two parties over a network, such as the internet, by using encryption, authentication, and integrity mechanisms. SSL and TLS operate at the transport layer of the OSI model, above the TCP protocol, which provides reliable and ordered delivery of data. SSL and TLS can be used to secure various application layer protocols, such as HTTP, SMTP, FTP, and so on. SSL and TLS do not provide nonrepudiation by default, as this is a service that requires digital signatures and certificates to prove the origin and content of a message. SSL and TLS do provide security for most routed protocols, as they can encrypt and authenticate any data that is transmitted over TCP. SSL and TLS do not provide header encapsulation over HTTP, as this is a function of the HTTPS protocol, which is a combination of HTTP and SSL/TLS.