Tag: dns

Firefox Extension Boosts Browser Security

August 27, 2008 by Jason

The Carnegie-Mellon University (CMU) made available a Firefox extension developed at their School of Computer Science and College of Engineering that improves security in Firefox by protecting against man-in-the-middle attacks. The extension, named Perspectives, is available only for Firefox 3 and works on Windows, Linux (32-bit) and OS X (Intel), with support for Linux (64-bit) and Open Solaris being in the experimental stage of development.

A man-in-the-middle attack is performed by intercepting the traffic between a user and a resource that he is trying to access. This can be achieved by exploiting several vulnerabilities, like the latest DNS cache poisoning or GMail accounts hacking incidents show.

When accessing a server resource using secure protocols like SSL or SSH, a correct identification of the server is required. This is achieved through digitally signed certificates. Due to the fact that certificates issued by trusted authorities like VeriSign are expensive, it became common practice for small businesses and websites to use self-signed certificates. Read More»

Microsoft Offers TCP/IP Fundamentals for Windows

June 02, 2008 by Jason

TCP/IP, an acronym for Transmission Control Protocol/Internet Protocol, is a suite of protocols supported by Microsoft with the Windows family of platforms. Essentially, through its components, TCP/IP is used for communications on both private networks and on the Internet. As far as the world wide web is concerned, the most common aspects of TCP/IP are IPv4 (Internet Protocol version 4) and IPv6. The Redmond company is offering extensive documentation on TCP/IP as it is supported in Windows Vista, Windows Server 2008, Windows Server 2003 and Window XP. TCP/IP Fundamentals for Microsoft Windows is available for download.

“This online book is a structured, introductory approach to the basic concepts and principles of the Transmission Control Protocol/Internet Protocol (TCP/IP) protocol suite, how the most important protocols function, and their basic configuration in the Microsoft Windows Vista, Windows Server 2008, Windows XP, and Windows Server 2003 families of operating systems,” revealed Keith Combs, Microsoft IT Pro Evangelist, citing an excerpt of the documentation’s description. Read More»

Howto clear/Flush DNS Cache in Ubuntu

January 14, 2008 by Jason

Some distributions run a caching nameserver in the background out of the box while some do not. To clear the cache if you have such a daemon running, simply restart the nscd service in ubuntu.

Most DNS clients will cache the results of name resolution request to speed up multiple lookups to the same URL. Just think about how many requests are made to the same domain when visiting a single web page. Every file, image, style sheet, etc. that is on that page and served from the same domain requires a DNS lookup. Read More»