Internet Protocol (IP) Address Interview Preparation Guide

IP addresses are used to transfer information across the internet. If you type www.ibm.com into your browser, your computer resolves this friendly name into the equivalent IP Address of IBM’s webserver, and then retrieves their homepage using this IP address. While you are connected to the internet, you are assigned a unique IP address as well, which is shown at the top of this page. IP addresses are defined in the TCP/IP protocol family, which is the basic technical foundation of the internet.

The IP address shown on this site is always the correct internet address, which is seen by all webservers and hosts you visit. If your computer has a network card and is connected to other PCs at your site, then you have a second, local IP address which is different from the internet address of your DUN connection or your firewall or router, which substitute all internal addresses with a true internet IP address.

DNS stands for domain name service. It can be thought of as a large, distributed database, containing all internet domain names and hosts, such as www.mywebsite.com. The reason for using DNS names instead of IP addresses is simple: meaningful names are much easier to deal with by human beings than numbers, such 212.202.126.70 If you are using a Dialin or DSL connection to your provider, the DNS name shown is probably a somewhat cryptic name, which is used by your provider internally to organize and manage the numerous dialin ports.

Domain names are like trademarks: competitive names are valuable and much sought-after. They are basically given on a first-come first-serve basis by international organizations, such as ICANN, DENIC, and several local organizations responsible for one ore more top level domains, such as .com, .gov, .de, .info and so on. The mechanism to query the current, registered owner of a domain name is called WHOIS. Type in any domain name, such as www.globalguideline.com or any ip address to find out the legitimate owner.

In an attempt to fight spam, several organizations began building black lists in order to ban domain names or IP address ranges that were accursed to be involved in unwanted practices. Many large organizations use these block lists to filter incoming emails. If you notice that some of your emails consistently fail to reach specific recipients and you verified the email address for validity, check if your IP address is blocked and, if so, talk to your provider to rectify the situation. If this happens more than once, get yourself another, better provider.

Most people think of the internet as surfing, downloading and mail, period. They simply use their internet connection to access some outside services. But imagine what could be done if you reverse the direction: Accessing your computer (or network) from the outside world will eventually open up a whole set of exciting new possibilities, like sharing data with customers and suppliers, IP telephony, video conferencing, remote control or working abroad, monitoring and controlling your premises and much more. All of these services need to access your computer or firewall by using its internet IP address as a doorway. Even if you don’t become excited about these possibilities, rest assured that many others are! Marketing companies geolocate your ip address, track your browsing habits with cookies or spyware and hackers are running robots to locate unsecured PCs. So this website will be dedicated to everything that could be done by accessing this doorway (your IP address), including important questions of security and privacy that will inevitably arise. If this sounds interesting, stay tuned!

An IP Address is a unique number used to identify a computer or a network device in the network or on the Internet. An IP Address looks like the following,xxx.xxx.xxx.xxx where x is a decimal representation of the equivalent Hexadecimal value. As you can see, there are 4 Octets split by three DOTS. This way of representing an IP address is called DOT Notation. An IP Address comprises of 2 parts. A Network ID and a Host ID. In simple words, its like the Street Address and the Door Number, where Street Address is your Network ID and the Door number is the unique host ID.

Well, thats where there comes in a new component called Subnet Mask which allows systems to differentiate between Host ID and the Network ID.

A Subnet Mask is an address mask that allows, systems to differentiate between the Network ID from that that of the Host Ids in a IP Address. This is represented very much as how an Ip address is represented.

As the Internet is flooded with more and more networks and computers, the system is now slowly running out of available addresses to fit in more networks or computers. For this reason, IPV6 is being designed. This is a new version of the IP protocol addressing method (V6 is Version 6) which is to slowly and steadily replace the existing IPV4 (V4 is version 4).