Information security has become a vital part of people's life, especially for those people who spend much time online. Tons of data are being transmitted over the internet every second. These data include user ids, passwords, credit card information etc and some of them are sensitive information which needs secure way to transmit. Hence different protocols have been developed including SSL/TLS to encrypt data transmitted over the internet.The core of these security protocols is the certificate used to prove the identity of the server and client, and keys in the certificate will be used to...

Secure communication has become a vital requirement on the Internet. Lots of information transferred through the Internet are sensitive data such as financial transactions, medical information, media streaming etc. To ensure security of data transferred on the Internet, a few secure protocols have been designed including SSL/TLS and IPsec. Many large websites in the world have adopted TLS. Apart from SSL/TLS, there is some other protocol designed to be used in special cases. One of them is the DTLS -- Datagram Transport Layer Security protocol.What is DTLSDTLS is a secure data transfer pr...

Spam comments are annoying and notorious. They are either malicious data from hackers to exploit the loopholes of the site or advertisements posted by robots. These kinds of comments have their own features and patterns, if we are careful enough, we can find ways to block most of them although it's not so easy.To block the comment with malicious executable codes such as JavaScript, we should remember one rule : never trust user input. So wherever there are user inputs, we need to check the validity of the data, we should escape the data inputted by users and remove unnecessary HTML tags from t...

The history of computer virus is the same as computer history. With more and more powerful computers, virus also are smarter and harder to be detected and killed. They have big impact on data security and system usability. We introduce 10 notorious computer virus in the history.1. CreeperIn 1971, the Creeper virus, an experimental self-replicating program, is written by Bob Thomas at BBN Technologies. Creeper infected DEC PDP-10 computers running the TENEX operating system. Creeper gained access via the ARPANET and copied itself to the remote system where the...

We need to build a password protected website frequently such as an internal website within the team, demo website. Here what we are talking about is password protection in Nginx server level instead of application level registration and login. We are going to use Nginx server configuration and htpasswd file to achieve password authentication.The final result looks like below(Different browsers may have different interfaces):If the authentication fails, it will report a HTTP error: 401 Authorization Required.To achieve this function, we need to modify server configuration and create the userna...

Weak password is a serious security vulnerability, but the majority of network users still use some universal simple character sequences as the password.SplashData recently announced the world's worst password list in 2012.  "password","123456" and "12345678" are still at top places, while others have varying,  some new passwords like  "welcome" "Jesus" "ninja","mustang"and "password1 "are in the list.With the risk of password loss, SplashData CEO Morgan Slain said we hoped network users should be more careful about ourselves network status, be more conscious about password secu...

Sometimes if you want to hide some important files on your computer which you don't want others to see, how would you do that? Find a professional tool? Set password for some folders? Change the file properties to hidden? They are possible, but they may not be so convenient or so secure. Here we share with you how to hide a file in a picture.Prerequisites1 picture for example : test.jpg1 test file, for example : test.txtWinRARStepsPrepare the picture test.jpg and test file test.txtUse WinRAR to compress test.txt to test.rarOpen command prompt : Start->Run->Type "cmd", then cd to the dire...

A given hash uniquely represents a file, or any arbitrary collection of data. At least in theory. This is a 128-bit MD5 hash you're looking at above, so it can represent at most 2128 unique items, or 340 trillion trillion trillion. In reality the usable space is substantially less; you can start seeing significant collisions once you've filled half the space, but half of an impossibly large number is still impossibly large.Back in 2005, I wondered about the difference between a checksum and a hash. You can think of a checksum as a person's full name: Eubediah Q. Horsefeathers. It's a shortcut ...