GNS3 is a fantastic piece of software, it glues together different open source software and allows to emulate a network that includes Cisco routers (using real Cisco firmware), Cisco switches (using IOU, Cisco IOS on Unix), Cisco ASA and any other devices that can run on Qemu or Virtual Box emulator.
It also allows to connect the virtual network to the physical network, it is possible to access Internet in the emulated world and vice-versa. GNS3 is available on Windows, Mac OSX and on Linux, but it shines on Linux because, to use IOU, if you are not on Linux you need a Linux virtual machine running on VirtualBox.… Read the rest
I am not a fan of Microsoft products, I don’t like their complexity and the “dangerous by design” philosophy; recently I switched company and I am involved in implementing a data center for a public institution based primary on Microsoft Technology. One of this product is Microsoft Exchange; after many years of Unix System Management experience I didn’t believe how flawed Exchange was until I red by myself the official Microsoft Exchange documentation (Microsoft Exchange Server 2003 Resource Kit).… Read the rest
The increase of Spam is a trend that started few years ago and it is continuously expanding, but to fight it there is plenty of good Open Source software. To use it effectively, anyway, it is needed a good knowledge of how spam floods our inboxes.
How spammers collect email addresses
The most used address gathering technique is using virus and spyware software that, without user awareness, gather email addresses from Outlook (or other email software) address-books and send this information to the spammers.… Read the rest