The best quality commercial software can cost hundreds and even thousands of dollars. If you can’t afford this expensive software, you can often find free open source software with the same features for free

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Best Free Open Source Software Programs for Windows
A signcryption scheme allows a sender to produce a ciphertext for a receiver so that both confidentiality and non-repudiation can be ensured. It is built to be more efficient and secure, for example, supporting insider security, when compared with the conventional sign-then-encrypt approach. In this paper, we propose a new notion called heterogeneous signcryption in which the sender has an identity-based secret key while the receiver is holding a certificate-based public key pair
ZigBee is a wireless sensor network standard that defines network and application layers on top of IEEE 802.15.4’s physical and medium access control layers. In the latest version of ZigBee, enhancements are prescribed for the security sublayer but we show in this paper that problems persist. In particular, we show that the end-to-end application key establishment protocol is flawed and we propose a secure protocol instead
You see a lot of products out there purporting to help you get back that speed that your computer has lost over time as you’ve cruised the Internet picking up cookies, installed programs and maybe sometimes unplugged your computer before remembering to shut it off. Microsoft apparently understands that computers running their operating system need some tweaking and/or maintenance from time to time, so that’s why they’ve included some tools to help users get back some, it not all, of the speed they’ve lost.

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Use Microsoft’s Optimizing Tools to Keep your Windows 7 Computer Running Fast
Macros are sequences of keystrokes or commands that can be saved in OpenOffice. You can use macros to automate frequent tasks, such as typing your name, address, telephone number or email address. The simplest way to create a macro is to use the built-in macro recorder that comes with the OpenOffice suite of software

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How to Record, Edit and Use Macros in OpenOffice Writer