Transport Layer Security (TLS) is an important part of the network security protocol for organizations of any size, including managed service providers (MSPs). It is designed to protect data from hacker attacks and help ensure the security of sensitive information such as passwords and credit card numbers. MSP can play its role by ensuring that its customers use the TLS protocol for maximum security in all web-based communications. In the following article, we will understand what Transport Layer Security is, how it works, and answer other common questions about its implementation.
What is TLS?
Transport layer security is an encryption protocol designed to provide end-to-end security for Web-based communications. The Internet Engineering Task Force (IETF) established TLS as a standard protocol to prevent tampering and eavesdropping.
When browsing the Internet, users and Web applications often encounter multiple possible security issues. These include verifying the identity of the other party, data tampering, and third-party monitoring. Transport Layer Security uses encryption technology to authenticate the client or server in the connection, helps ensure the integrity of the data being transmitted, and provides protection throughout the browsing session.
Users usually recognize TLS from secure web browsing, where online transactions are protected from hackers and eavesdroppers. The safe browsing session is indicated by the padlock icon in the upper left corner of the web browser. It is also used in applications such as email, file transfer, video and audio conferencing. It is also compatible with a large number of protocols, including HTTP, SMTP, FTP, XMPP, etc. Users should note that TLS is not designed to protect data on end systems, but only to protect data transmitted over the Internet.
TLS evolved from Secure Sockets Layer (SSL). SSL was originally developed by Netscape Communications Corporation in 1994 to protect Web sessions. SSL 1.0 was never publicly released, and SSL 2.0 was quickly replaced by SSL 3.0 on which TLS is based. TLS turned into first specified in RFC 2246 ] in 1999 as a packages impartial protocol, and at the same time as turned into not directly interoperable with SSL 3. 0, which presented a fallback mode if important. But, SSL 3. 0 is now considered insecure and has become deprecated via RFC 7568 in June 2015, with the advice that TLS 1. 2 must be used. TLS 1.3 is likewise presently (as of December 2015) under development and will drop support for less secure algorithms.
How Does TLS Work?
TLS safety is designed to apply encryption from each client and server ends to help ensure a safe connection between two or greater communicating packages, assure interoperability between devices, and function with relative performance.
Client-server communication begins by indicating whether or not communications will proceed with or without TLS protocols. The client can specify a Transport Layer Security connection in a selection of approaches. For example, the client would possibly use a port variety that helps the sorts of encryptions utilized in TLS communications. Another potential technique is to make a protocol-precise request to switch to a Transport Layer Security connection.
After the client and server have agreed to communicate using Transport Layer Security, the TLS protocol specification continues through two layers: TLS handshake protocol and TLS recording protocol. Transport Layer Security protocols use symmetrical and asymmetrical cryptographic combinations. Symmetrical cryptography creates a key that is known by the sender and receiver, while asymmetrical cryptography produces a key pair – one public (sharing between senders and recipients) and one private.
The specifications needed to exchange the application “Message” are set in the Handshake TLS protocol. TLS Handshake involves a series of exchanges between clients and servers that vary based on the key exchange algorithm used and the compiled cypher suite, but can be revealed as follows:
- A client sends a message “HELLO client” requesting a connection and has a list of the supported dials (a set of encryption algorithms used to establish a secure connection and a random chain of bytes (called “random client”).
- The server responds with a message “Server Hello” containing the selected TLS protocol version (1.0, 1.2, etc.), the chosen encryption sequence and a random string of bytes (called “random server”).
- The server sends its SSL certificate to the client for authentication. The customer authenticates the server when verifying the SSL certificate and can also send a certificate for authentication if requested by the server.
- The client sends a second series of random bytes, the “premaster secret”. The client uses asymmetric cryptography to generate a public key from the Security Certificate of the Server, which is then used to encrypt the secret of the prize. The secret of the prize can only be deciphered with the private key by the server.
- The server decrypts the secret of the premaster with the private key.
- Both the client and the server generate session keys of the client random, random from the server and the secret of the premaster.
- The client sends a “finished” message that has been encrypted with a session key.
- The client and the server have successfully achieved safe symmetrical encryption, which means that the handshake is complete and communication can continue with the session keys set.
Once the decryption method is established during the handshake procedure, the TLS record protocol uses symmetric cryptography to generate unique session keys for each connection that allows continuous communication throughout the session. The registration protocol also attaches to the data that is sent with a Hash-based message authentication code (HMAC).
Because the Encryption Protocols in Transport Layer Security are complex, users should expect to spend some calculation power in the process. But TLS also has internal techniques instead to prevent significant delays. As a result, Transport Layer Security protocols should not significantly affect the performance of the web application and loading times, nor should they increase computational costs for most organizations.
The benefits of Transport Layer Security
The benefits of TLS are simple when discussed using versus not using TLS. As noted above, an encrypted TLS session provides a secure authentication mechanism, data encryption and data integrity checks. However, when comparing Transport Layer Security to another set of authentication and secure encryption protocol, such as Internet Protocol Security, Transport Layer Security offers additional benefits and is a reason why IPsec is being replaced with TLS in many situations of implementation of the company. These include benefits like the following:
- Safety is directly constructed in each application, unlike the external software or hardware to build IPsec tunnels.
- There is true end-to-end encryption (E2EE) between the communication devices.
- There is granular control over what can be transmitted or received in an encrypted session.
- Since TLS operates within the upper layers of the Open Systems Interconnection (OSI) model, it doesn’t have the network address translation (NAT) complications that are inherent to IPsec.
- TLS offers logging and auditing functions that are built directly into the protocol.
The challenges of TLS
There are several disadvantages in that not to use any safe authentication or encryption – or when deciding between Transport Layer Security and other security protocols, such as IPsec. Here are a few examples:
- Because TLS operates in layers 4 to 7 of the OSI model, as opposed to Layer 3, which is the case with IPsec, each application and any communication stream between the client and the server must create the TLS session itself to get the benefits of authentication and data encryption.
- The possibility of using TLS depends on whether each application supports it.
- Because TLS is implemented on an application basis to better improve granularity and control of encrypted sessions, this is the cost of increased overhead management.
- Now that TLS is gaining popularity, the threat actors are more focused on the discovery and exploitation of potential TLS exploits that can be used to compromise the security and integrity of the data.