An Internet Protocol (IP) address is a numerical identifier that is assigned to every device or machine in a computer network. If you are planning to start your own Internet business, using a virtual private network VPN or VOIP, you need to be adequately informed about IP addressing. We all (should) know – there are static and dynamic IP addresses. But when should you use them?
What is a Dynamic IP Address?
A dynamic IP address changes each time you boot your machine or network device. It also changes when you dial into your Internet service provider. Some ISPs change your IP each time you log on to their network while some make the changes periodically.
Most dynamic IP addresses are assigned using the Dynamic Host Configuration Protocol (DHCP). The router on your home network assigns IP addresses to your computers and other network devices as you put them on. Private IP addresses usually have this format: 192.168.0.x. Your router’s IP address will usually be 192.168.0.1 while your computers will be assigned numbers ranging from 192.168.0.2 to 192.168.0.254.
In situations where you need to remotely administer a particular computer on a network, you may need to reserve a particular address for it. To assign static IPs to certain computers and dynamic IPs to others on the same network, you should reserve the IPs for the specific machines on the DHCP server. This will help you to administer the network centrally without the need to assign static IPs manually. It will also prevent the occurrence of IP conflicts.
When Should You Use Dynamic Ips?
Dynamic IPs will be good for anyone who uses their computer or home network for the following:
* To browse the Internet and upload or download files
* To send and receive email through a mail server or via a web based email service like yahoo mail, hotmail or gmail.
* To use online chat services or instant messaging
* To use FTP servers or web servers that only require access from your LAN or corporate network but do not require access from the Internet.
What is a Static IP Address?
A static IP address is a fixed IP address that is manually assigned to a device on a network. It is called a static IP because it is not changed each time the device is switched on. Static addresses remain the same each time you connect to the network or send a message.
When Should You Use a Static IP?
Static IP addresses provide greater reliability for applications such as voice over Internet protocol (VOIP). If you run a service that permits incoming audio or video, you may need to use a static IP. For example if you have an on-site IP-PBX, you will need to have at least one static IP address.
A static IP will also be required if you have a machine that functions as a server and requires external access from the users online. This includes running a web server, e-mail server, FTP server, or DNS server. A static IP allows you to enjoy faster upload speeds which boost the efficiency of these services.
If you intend to host a gaming website or you want to use Play Station, X-Box or a VPN to provide secure access to files from your corporate network server, you should also consider buying a public static IP address.
How to Set Up a Static IP in Linux?
Here are the steps you should take to assign a static IP address on a Linux system.
1. Make sure you are logged on as root
2. Create a backup copy of the /etc/network/interfaces file on your machine. You can easily restore the backup if something goes wrong.
3. Edit the /etc/network/interfaces file. From the text console, you can load this file into the famous vi editor.
4. Scroll down the file until you locate the network interface card. An Ethernet connection is usually identified by eth0 or wlan0 while a wifi connection is identified as wifi0.
5. Replace “ iface eth0 inet dhcp “ with “ iface eth0 inet static “.
6. Add these lines: (you can replace the address and dns nameserver with your own configuration)
address 192.168.0.5
netmask 255.255.255.0
network 192.168.0.0
gateway 192.168.0.0
dns-name-servers 216.10.119.241
If you are running Slackware or Red Hat Linux, one of the simplest methods is to log on as root and then type ifconfig/netstat at the console. You can then use the text-based menu to modify the configuration settings.
In Slackware the settings will take effect instantly. But in Red Hat you need to type “ service network restart “ and press enter.
