What is a static IP?

[panais]

What is a static IP?
are there any benefits from it?

 

[scrooge]

Static IP addresses are manually assigned to a computer by an administrator. The exact procedure varies according to platform. This contrasts with dynamic IP addresses, which are assigned either by the computer interface or host software itself, as in Zeroconf, or assigned by a server using Dynamic Host Configuration Protocol (DHCP). Even though IP addresses assigned using DHCP may stay the same for long periods of time, they can generally change. In some cases, a network administrator may implement dynamically assigned static IP addresses. In this case, a DHCP server is used, but it is specifically configured to always assign the same IP address to a particular computer. This allows static IP addresses to be configured centrally, without having to specifically configure each computer on the network in a manual procedure.
In the absence or failure of static or stateful (DHCP) address configurations, an operating system may assign an IP address to a network interface using state-less auto-configuration methods, such as Zeroconf.

 

[mickey megabyte]

...or in simple terms:

every time your computer connects to a network, it is given a unique identifier - an ip address, so your router can tell one machine apart from another. this isn't necessarily the same each time. setting a static ip in your router settings makes sure that each computer always gets the same ip address each and every time. this is useful for several reasons, including if you need to forward any ports on a particular machine.

similarly, every time your computer (or rather your router) connects to the internet, your isp gives your machine a unique ip address, so the right stuff gets to your computer.

normally you'll have a 'dynamic ip' so each time you connect, you'll have a different ip, depending on how many other users there are on the network. however you could request a static ip, which means your computer will always be x.x.x.x on the internet. this is essential if you want to run a server.

most users don't need it, and most isp's that i've known charge extra for it.

 

[Ztruker]

A static IP is normally used by someone who wants to run a server of some kind (web or game) that other people can connect to.

 

[pparks1]

A static IP address is one that you set manually that doesn't change. Easy as that.

 

[jcahow]

To answer you inquiry about why a static IP might be used. They are used when something on the network/internet needs to be consistently referenced, since a dynamic IP can change over time.

DNS servers convert web addresses (www.xxx.com) for example to specific IP addresses so that their servers can be specifically referenced.

If you have a static IP you could assign it to a device at your location and access it remotely. For instance you could print to a networked laser printer at home from your office, access files off a home computer, or setup an online game/mail server. This assumes you have home router setup correctly to allow requests to pass through and be routed to that static IP address.

Static IP addresses are not common because they have to be specifcally assigned by your ISP (if they even allow this service) and they will charge you extra for this service. They also eat up one of your ISP's available IP addresses (assuming you also have a dynamic IP) as it cannot be reassigned to someone else.

There are a number of Dynamic IP services available that will take your dynamic IP address and treat it as a static IP address. They do this by watching/polling your IP address and constantly pointing at the current IP address. That way a web address (www.xxx.com) will consistently point to you even if your ISP assigns a new IP address but these services charge as well (some routers even have this service built into their firmware).

With the advent of all the file and picture sharing web sites (either through your ISP or alternate vendors) and the limited number if IPv4 addresses available the use of static IPs has never taken off except for web servers.