Tag: Encryption in Networks

asymmetric key: An approach to encryption where one (public) key is used to encrypt data prior to transmission and a different (private) key is used to decrypt data once it is received. certificate authority: An organization that digitally signs public keys after verifying that the name listed in the public key is actually the person…

You can take this quiz online at http://www.net-intro.com/quiz/ How do we indicate that we want a secure connection when using a web browser? a) Use https:// in the URL b) Use a secure web browser c) Open an incognito windowd) Manually encode the address of the server using SHA1 Why is a shared-secret approach not…

Since the Internet was nearly 20 years old before we needed broadly deployed security, we had to find a way to add security to the already existing four-layer model. The perfect place to add security was as an option in the Transport layer. This is why we call secure connections on the Internet “Secure Sockets…

While public/private key encryption works to allow the distribution of encryption keys across insecure networks and the use of those keys to encrypt transmissions, there is still a problem of knowing if the public key that you have received when you connected to a server is really from the organization it claims to be from.…

Since web browsers and web servers operate at the application layer, we barely notice whether we are using encrypted or unencrypted connections. Web browsers use the URL convention of replacing “http:” with “https:” to indicate that the browser is to communicate with the web server using the Secure Transport Layer instead of the unencrypted Transport…

Since network engineers decided to add security nearly 20 years after the Internet protocols were developed, it was important not to break any existing Internet protocols or architecture. Their solution was to add an optional partial layer between the Transport layer and the Application layer. They called this partial layer the Secure Sockets Layer (SSL)…

The traditional way to encrypt transmissions is using a shared secret (a password, a sentence, a number) that only the sending and receiving parties know. With the secret, it is easy to decrypt the received data, but if you received the data without possessing the secret, it would be effectively impossible to decrypt the message.…

The concept of protecting information so it cannot be read while it is being transported over an insecure medium is thousands of years old. The leaders in Roman armies sent coded messages to each other using a code called the “Caesar Cipher”. The simplest version of this approach is to take each of the characters…

In the early days of the Internet, networks were small and all of the routers were in secure locations. As long as each computer connected to the Internet protected itself from unwanted incoming connections, it was felt that there was no need to protect data from prying eyes while it was crossing the network. So…