The time required to crack an encryption algorithm is directly related to the length of the key used to secure the data.

Every so often, we encounter someone still using antiquated DES for encryption. If your organization hasn’t switched to the Advanced Encryption Standard (AES), it’s time for an upgrade. To better understand why: let’s compare DES and AES encryption:

iOS and Android’s Bluetooth APIs allow apps to communicate with BLE devices. The API simplifies the way apps implement BLE and allows multiple apps to use BLE at the same time, but it also introduces many undocumented behaviors. Unfortunately, the only way to understand these behaviors is through experimentation. The behavior we’ll be focusing on today is how iOS and Android handle reconnecting to disconnected human interface devices.

Closures are self-contained blocks of functionality that can be passed around and used in your code. Closures in Swift are similar to blocks in C and Objective-C and to lambdas in other programming languages.

Closures can capture and store references to any constants and variables from the context in which they are defined. This is known as closing over those constants and variables. Swift handles all of the memory management of capturing for you.

NOTE

Don’t worry if you are not familiar with the concept of capturing. It is explained in detail below in Capturing Values.

Git commands are an essential lesson that every developer needs to master at some point. To use the full potential of Git, the popular version control system, you need to know how to use Git commands.

In this tutorial, you will find all the commonly used Git commands as well as a downloadable cheat sheet.

git init [directory]
git clone [repo / URL]
git clone [repo / URL] [folder]
git config --global user.name "[your_name]"

To login (from unix shell) use -h only if needed.

[mysql dir]/bin/mysql -h hostname -u username -p password

To login (from windows)

[mysql dir]/bin/mysql.exe -h hostname -u username -p password

Create a database.

mysql> create database [databasename];

List all databases on the server.

mysql> show databases;

Switch to a database.

mysql> use [db name];

While full-disk and file-based encryption goes a long way to protecting the data stored on an Android device, for some especially sensitive data like passwords etc., this may not be enough.

The problem is that if an attacker is able to compromise the Linux kernel or gain root access via some other means, then since the kernel is able to read the unencrypted contents of any files stored on the device (once the user has entered their password), the attacker can gain access to any sensitive data. Also, even if an attacker is not able to gain root access, if they can nonetheless compromise your app, then they can gain access to your app’s data.

The solution is to directly encrypt the most sensitive data before storing it.

Getting this right though is hard, and we strongly recommend you speak to a security expert before attempting this.