Transport Layer Security and Secure Shell

The root cause of the security protocol being implemented in the network is simple. Protects data as it passes through the network. The mechanism associated with the protection of travel data is called encryption. This special mechanism uses an algorithm that encrypts data to prevent hackers from easily intercepting data. Encryption works in conjunction with a set of protocols that help control data transfer between network devices. Therefore, security protocols are an important part of the network to improve data security, otherwise security is affected (Linn, 2014).

SSL / TLS (Transport Layer Security): TLS is an encryption protocol that provides communication security over a computer network. SSL (Secure Sockets Layer) is the predecessor of deprecated use of TLS. Both TLS and SSL use a certificate to establish a secure connection. The SSL certificate does not depend on the encryption protocol (such as TLS), and the certificate contains the key pair of the public key and the private key. These keys work together to establish an encrypted connection. TCP connection: the time it takes to establish a TCP connection between the source host and the target host. It is necessary to establish the connection correctly during multi-step handshake. If the TCP connection is managed by the operating system and the underlying TCP connection can not be established, the TCP connection timeout of the entire OS will refuse the application timeout setting.

TLS stands for Transport Layer Security, which is the encryption layer above TCP. We will resolve both problems by verifying the identity of the host and encrypting the message to be sent. To establish a TLS connection, an additional three-way handshake is performed after the first TCP handshake. After the TLS connection is established, HTTP requests and responses are sent to known trusted hosts and the HTTP message body is encrypted. This is called HTTP Secure or HTTPS.

The Transport Layer Security (TLS) protocol is divided into two phases: handshake and data transfer. During the handshake phase, both the client and the server understand each other 's encryption capabilities and establish an encryption key to protect the data transfer. Data transfer is done at the end of the handshake. The data is divided into a series of records, protected by the encryption key established in the first phase, and sent between the client and the server. Figure 7 shows how TLS fits into the other transport and application layer protocols. TLS was originally designed to work with reliable transport protocols such as TCP (Transmission Control Protocol). However, TLS is also used for untrusted transport layer protocols such as User Datagram Protocol (UDP). RFC 6347 defines datagram transport layer security (DTLS) 2 equivalent to TLS in the UDP world. This blog focuses on TLS only