STATIC IP ADDRESS Vs DYNAMIC IP ADDRESS:

FIRST KNOW WHAT IS IP (INTERNET PROTOCOL ) ADDRESS:

This number is an exclusive number all information technology devices use which identifies and allows them the ability to communicate with each other on a computer network. There is a standard of communication which is called an Internet Protocol standard.

An IP address identifies a computer or other device to a network.. Every device on a network needs to have its own address. that way, data is sent to the right place. There are IP addresses are used by the whole Internet, and others, only used by locally, for example in your home.

WHY WE NEED IP ADDRESS: 

The IP address is basically the address that distinguishes where you want to send information to, and from where the information comes. There simply has to be a way to distinguish with which of the millions of computers in the World you want to communicate.

The IP address is a layer 3 address. It is designed and intended to refer to a specific network and because the internet address pool is centrally managed it provides the network with the information needed to get the data anywhere in the world. 

IP addresses may either be assigned permanently for an Email server/Business server or a permanent home resident or temporarily, from a pool of available addresses (first come first serve) from your Internet Service Provider. A permanent number may not be available in all areas and may cost extra so be sure to ask your ISP.

Domain Name System (DNS): This allows the IP address to be translated to words. It is much easier for us to remember a word than a series of numbers. The same is true for email addresses.

THE IP ADDRESS FROM YOUR ISP IS ASSIGNED ONE OF TWO WAYS:

* Set to an IP address which is unchanged for months or years at a time. This is a static IP address.

* Set to an IP which is only good for a limited time, and which is changed according to the policy set by your ISP's DHCP server. This is a dynamic IP address.

Static IP addressing is for one customer on one IP address and Dynamic IP addressing assigns a different IP address each time the ISP customer logs on to their computer.

STATIC IP ADDRESS:

Because a static IP can be relied on for an indefinite period, some networking software requires a static IP. ISPs usually charge extra for static IPs. Your ISP may not be willing to give their customers static IP addresses at all.

This is an IP address that is allocated to you that does not change each time you access the Internet. You can use a static IP address to run an email server or even host a website, however, virtual hosting is very inexpensive so it would be most advisable to obtain a proper hosting solution.

Also known as a Dedicated IP Address, this is when a website has an unchanging IP address every time it is connected with a server. The opposite of this is a Dynamic IP address, where the system is assigned a new IP address every time it starts up. 

Static IP address assignment (sometimes also called fixed addressing) is an alternative to dynamic addressing (normally, DHCP) on Internet Protocol networks. Dynamic addressing is convenient. It also allows mobile computers to more easily move between different networks.

STATIC IP ADDRESSING ALSO OFFERS SOME ADVANTAGES:

• A static IP address best supports name resolution, so that a computer can be most reliably reached over the network by its host / domain name. Web and FTP servers in particular benefit from fixed addressing for this reason.
• Using static IP addresses on home networks gives somewhat better protection against network security problems than does DHCP address assignment.
• Some network devices do not support DHCP. Using static IP address assignment for all devices on the home network guarantees to avoid potential address conflicts where DHCP may supply an address already assigned statically elsewhere.

DYNAMIC IP ADDRESS:

Dynamic IPs are used in large networks where computers are frequently reconfigured, or where a limited number of IP address are available to share between many computers. 

The Dynamic Host Configuration Protocol (DHCP) is a computer networking protocol used by hosts (DHCP

clients) to retrieve IP address assignments and other configuration information.A variable IP address that is delegated to a computer or server each time it is connected to the Internet. Many ISPs use a dynamic IP address system in order to reduce the number of IP addresses they need to maintain.

THE BIGGEST ADVANTAGES OF DYNAMIC IP ADDRESSING:

Dynamic IP Addressing are less security risk as the computer is assigned a new IP address each time the customer logs on, they are cost effective and there is automatic network configuration (the less human intervention with network configuration the better). Dynamic addressing is usually used by ISP's so that one IP address can be assigned to several users, however some ISP's use Sticky Dynamic IP Addressing and do not change the IP address very often. Dynamic IP Addressing can be used by families with several computers or by a small business owner who has a home office. The software that comes with a router allows for Dynamic Host Configuration Protocol (DHCP) setup and assigns each computer attached to the router an IP address automatically.

 

WHEN WE DON'T WANT STATIC IP ADDRESS:

If you ONLY do things from the following list you do not need static IP addresses.

1. If you browse the Internet.
2. If you send and receive e-mail via an offsite mail server or service (the normal method and typically using your ISP's mail server(s) or a mail service such as gmail, hotmail, yahoo mail etc.).
3. If you download or upload files.
4. If you use Instant message services or chat services.
5. If you run any services, such as web or FTP servers, that ONLY require access from your local area network (single site) and that DO NOT require or ALLOW access from the Internet. 

WHEN WE NEED STATIC IP ADDRESS: 

• When we run one or more Web server's directly on your site that require external access.
• When we run one or more FTP server's directly on your site that require external access.
• When we run one or more E-mail server's directly on your site that require external access.
• When we allow 'incoming' Video Conferencing you may need to use static IP addresses.
• When we run any other service or 'Application' that requires external access. For example some peer-to-peer, game applications require that you have a static IP address for licensing purposes.
• When we require or allow 'incoming' Video or Audio services. In this case you may need to use static IP addresses. 

When using static IP addresses on home and other private networks, they should be chosen from within the standard private IP address ranges listed:

• 10.0.0.0 through 10.255.255.255
• 172.16.0.0 through 172.31.255.255
• 192.168.0.0 through 192.168.255.255

TO CHOOSE AND SET SPECIFIC STATIC IP ADDRESSES SUITABLE FOR YOUR NETWORK, FOLLOW THESE GUIDELINES:

1. Do not choose any addresses that end with ".0" or ".255" - these addresses are generally reserved for use by network protocols.
2. Do not choose the addresses at the beginning of a private range. IP addresses like 10.0.0.1 and 192.168.0.1 are very commonly used by network routers and other consumer devices. These are the first addresses someone will attack when trying to break into a private computer network.
3. Do not choose an address that falls outside the range of your network mask. For example, to support all addresses in the 10.x.x.x private range, the network mask on all devices must be set to 255.0.0.0, otherwise some static IP addresses in this range will not work.

This Article Written Author By: Premakumar Thevathasan. CCNA, CCNP, CCIP, MCSA, MCSE, MCSA - MSG, CIW Security Analyst, CompTIA Certified A+.