Security

Key Storage

One of the primary difficulties in establishing good security through cryptography is key storage. In order for a key to be useful, it must be persistent. But by keeping the key around, we risk it being compromised. Let’s imagine that we want to encrypt some personal files on our computer so that no one can read them. We create a 448-bit Blowfish key and encrypt our files with it, thinking that our files will now be secure. But if someone were to get into our machine, they’d be able to read the key and decrypt the files. In order for the files to be safe, we have to protect the key that we used to encrypt those files.

Password-Based Encryption (PBE)

The examples that we’ve given so far have used binary keys. These keys need to be stored in some fashion –  on a hard drive or floppy disk for instance. Password-based encryption (PBE) uses a password as the key. This is convenient because the security then rests with the user rather than in a physical medium. Unfortunately, password-based encryption in general isn’t as secure as algorithms with binary keys like TripleDES or Blowfish. To demonstrate this, let’s say we use Blowfish with a key size of 128 bits. That gives us a keyspace of 2128. Password-based encryption typically uses ASCII characters. An average user’s password might be 6 characters in length. If it’s entirely lowercase, there are only 266 possible keys, or roughly 228. Adding capital characters and symbols helps quite a bit, but it cannot even approach the keyspace of a good symmetric algorithm.

Symmetric Encryption

This chapter we’re going to elaborate on the subject by describing how to use the JCE to perform symmetric encryption. To begin with, we will look at how we encrypt and decrypt using symmetric encryption. Then we discuss applications for symmetric encryption, followed by some examples, which deal with the following aspects of encryption:

Basic encryption
Encryption using Blowfish
Password-based encryption
The main topics discussed in this chapter are:

The blacklists were incredibly simple to implement into RouterOS and once configured, the lists can be scheduled to update at regular intervals via the RouterOS system scheduler. Squidblacklist.org provides a list of available blacklists, but make sure to review the blacklist compatibility chart first, before implementing the list into your RouterOS configuration. In addition, you will need to change the “dst-path” value to an existing path for the script to work. If you want to download the blacklist to the root of your MikroTik you can delete the “dst-path” property and its value entirely . Also, make sure that the “in-interface” and “out-interface” property value is set to that of your network environments WAN interface. Should you choose the “All-In-One Firewall/Filter Setup” script (via copy/paste in the MikroTik terminal), you will need to enable the scheduled tasks, since they are disabled by default in the script.

Blocking Adult Sites Easy in Mikrotik
Creating a healthy internet atmosphere is important. Especially if the stout client of our network is children or school children who can not access adult content. The problem is, a lot of adult sites are circulating on the internet. This will make a headache if we have to block his site one by one.

To be able to block certain sites or content on the internet on Mikrotik can be done by: