The Web Technologies
The literal meaning and full forms of acronyms and terms Linux, Firewall, TCP/IP, DWDM. These are the technologies that virtually define the Web world.
Bewildered by the stream of acronyms and terms that characterize the wired world? Here's a low-tech guide for some high-tech technologies defining them.
TCP/IP (Transmission Control Protocol/Internet Protocol)
To many people, TCP/IP is the Internet. But it's not so honey! TCP/IP is actually a key protocol on which the Internet works. TCP/IP was originally developed for the US Dept. of Defense as a method of connecting dissimilar communications systems. Its purpose was to provide a transportation medium to carry vital message within a wide range in short time.
Although TCP/IP has became popular in last few years, it has been in use in Unix systems for long times. TCP/IP is a layered protocol, which means the data transfer takes place within numerous stages. TCP provide transport functions ensuring that the data bundles are received correctly at the other end. While IP provide the routing mechanism and is connectionless. The drawback is that it can't provide quality service and there isn't any priority e.g. between video and data.
Linux - Open source operating system.
Over the past year the free, open source code operating system based on Unix developed by Linus Trovalds, has received almost non-stop support from vendors and is forecasted to grow in leaps and bounds @ 23% per year and will cross Micorsoft's Windows NT by 2004. Linux has four distributors: Red Hat and Caldera in the US and UK, SuSE in Germany and Pacific Hi-Tech in Japan.
The fact that it's an open source operating system has helped to make Linux robust. Open means that anybody can take the original code and work on it, making changes where they like. This means that thousands of people have contributed to the evolution of Linux, detecting and rectifying problems and passing the information on. On the other hand, Windows is a closed operating system which only Microsoft engineers may alter.
Firewall - Network security barrier
Firewalls are another critical piece of the security puzzle. They are used both within a business as a barrier to protect sensitive information from prying eyes, and as a barrier between a company's public Web server and its internal network.
As the use of Internet increases and e-commerce Web sites proliferate, the need for the firewalls is heightened. It uses numerous techniques to afford protection. These include packet filtering, which blocks traffic according to IP addresses and/or port numbers and is also known as a screening router.
Overseeing security is an Internet Engineering Taskforce standard called ipsec, which defines how to perform basic encryption and security on top of IP. New ipsec's are launched all the time.
DWDM (Dense Wavelength Division Multiplexing)
Lack of bandwidth is one of the biggest problems facing the telecommunications and service provider networks, which are tasked with carrying much of the burden of Internet traffic.
With an office PC, he more memory space that is acquired, the faster it is used up, but the user has the option of buying more space. Where Internet is concerned, the answer isn't as simple. These organizations have traditionally had two options in the face of growing demand.
They could either lay new fibre optic cable or could increase the speed at which data is transmitted. Laying such cable is expensive and so too is the price of upgrading existing cables to run at faster rates.
Ciena Corporation developed Dwdm as an alternative in 1996. Today most of the major network equipment vendors, including Cisco Systems and Nortel Networks, intergrate dwdm into their high-end products.
Dwdm works by breaking a single white fibre light into its component wavelengths, or colours - imagine a rainbow - each of which can carry greater volumes of data. As it is not being transmitted at higher speeds, no fibre upgrades are needed.
Normal fibre carries an average of 32,000 phone calls or data transmissions per second but dwdm systems can increase that by up to 96 times, raising the capacity of the same fibre to over 3 million phone calls or data transmissions per second.
Dwdm can be used with atm and IP network switches which are increasingly being used in service provider networks, and can be used to create vpns (virtual private networks) on a per-wavelength basis, making them a more cost effective service for carriers to offer.