A static IP address is an IP address that was manually configured for a device, versus one that was assigned by a DHCP server. It’s called static because it doesn’t change. It’s the exact opposite of a dynamic IP address, which does change.
Static vs. Dynamic IP Addresses
The opposite of a never-changing static IP address is an ever-changing dynamic IP address. A dynamic IP address is a regular address like a static IP is, but it’s not permanently tied to a device. Instead, dynamic IP addresses are used for a specific amount of time and then returned to an address pool so that other devices can use them.
When to Use a Static vs Dynamic IP Address
This is one reason that dynamic IP addresses are useful. If an ISP used static IP addresses for their customers, there’d constantly be a limited supply of addresses for new customers. Dynamic addresses provide a way for IP addresses to be reused when they’re not in use elsewhere, providing internet access for more devices than would otherwise be possible.
Static IP addresses limit downtime. When dynamic addresses obtain a new IP address, any user that’s connected to the existing one is removed from the connection and has to wait to find the new address.
Disadvantages of Using a Static IP Address
The major disadvantage that static IP addresses have over dynamic addresses is that the devices must be configured manually. The examples given above with regards to a home web server and remote access programs require you to set up the device with an IP address and properly configure the router to communicate with that specific address.
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