Static IP
vs. dynamic IP
addresses:
Understanding
the difference

With the significance of network connectivity in today's connected world, it's essential to understand the difference between a static IP vs. dynamic IP address, their essential contribution to organizing the internet and how best to use them.

Deciding between a static IP vs. dynamic IP address can help an organization better support remote users, so they can access the devices they need, no matter where they are, as well as facilitate access to any data, digital information, or services they need to be productive.

Every device connected to the internet, or a private network using TCP/IP, has an assigned internet protocol (IP) address, acting as a unique identifier for that device.

The most popular network protocol in the world, TCP/IP (Transmission Control Protocol/Internet Protocol), is the standard internet communications protocol that allows devices to communicate over long distances. TCP is the component that breaks down and reassembles the packets of data, while IP is responsible for making sure the packets are sent to the right destination. We will explore IP in this article.

The IP address is a unique identifier for devices connected to a network, similar to a postal address. The first type of IP address was IPv4, which has been used since the inception of the internet. The IPv6 standard was created to accommodate the growth of internet-connected devices by offering more IP addresses, but to this day, IPv6 is still not enabled by all content and transit providers or products. Older computers and Wi-Fi routers, for example, may not be IPv6 capable.

IP addresses are managed and governed centrally through the Internet Assigned Numbers Authority, and although the depletion of the global supply of available IPv4 IP address space was announced in 2011, IPv4 are still widely used thanks to technologies like Classless Inter-Domain Routing (CIDR) and Dynamic Host Configuration Protocol (DHCP). CIDR is an addressing scheme that improves the allocation of IP addresses, while DHCP is a network management protocol used on IP networks for automatically assigning IP addresses.

What is the difference between a dynamic and static IP address? A static IP address is a permanent number assigned to a computer or device and does not change over time. However, a device that is connected to a dynamic IP address gets automatically assigned a temporary number that can change every time it reconnects with a network.

A key aspect of understanding the difference between static IP vs. dynamic IP addresses, is that they are not the only kinds of IP addresses. So exactly what is a static IP address and what are the other kinds of IP addresses?

• A private IP address is for internal customer/network use only and is not routed across the public internet Private IP networks provide simple, dedicated, restricted network environments that allow businesses to consolidate applications into a single, secure network infrastructure leveraging the IP protocol.
• A dynamic IP address is a temporary address for devices connected to a network that continually changes over time. Most devices use dynamic IP addresses, which are assigned by the network when they connect. Dynamic IP addresses are automatically assigned by the network via Dynamic Host Control Protocol (DHCP).
• A static IP address always stays the same. Devices with a static IP vs. dynamic IP address are often those accessed directly by customers, users and suppliers such as a web server, FTP server, or other Internet resources. Many ISP's use DHCP to assign addresses and make the dynamic address appear static by "locking" the assigned address so it never gets released. This is often used to assign businesses addresses that they want to stay the same.

When a static IP address is assigned to a device, it doesn't change until the associated services are disconnected or a request to release the IP address lease is submitted. Learn more in Verizon's IP Address Assignment and Usage Policy.

Static assignments, even through a "fixed" dynamic address, can help support identity-based protections to authenticate the identity of the user or device. This can allow you to adopt practices such as whitelisting or allowlisting and/or ensure users have the necessary authorization and permissions to access certain applications, data, or services. However, a static IP isn't necessary because it's possible to use dynamic Domain Name System (DNS), where permissions and access are tied behind the scenes. The address might change, but the access is provided through the DNS name.

This can be particularly useful for remote workers because static IPs can be used to verify permitted users to access a company network. Furthermore, the addition of private IP networking layers on security as each device will have their company's private IP address ahead of further authentication with the likes of multifactor authentication and single sign-on (SSO), not directly routed over the public internet.