10 IP Addressing Scheme Best Practices

IP Addressing is a fundamental networking concept. It’s the process of assigning numerical labels to devices connected to a network. The purpose of IP Addressing is to uniquely identify devices on a network so that they can communicate with each other.

There are a few different IP Addressing schemes in use today, but the most common is the IPv4 scheme. This scheme uses a 32-bit address space, which allows for a total of 4,294,967,296 unique addresses.

While this may seem like a lot, the IPv4 address space is actually running out. This is due to the fact that the world population is growing and more and more devices are being connected to the internet. As a result, a new IP Addressing scheme, known as IPv6, is being slowly adopted.

IPv6 uses a 128-bit address space, which allows for a total of 340,282,366,920,938,463,463,374,607,431,768,211,456 unique addresses. This is a vast improvement over the IPv4 address space and will be able to accommodate the needs of the internet for many years to come.

When designing an IP Addressing scheme, there are a few best practices that should be followed in order to ensure that the scheme is effective and efficient.

1. Use a private IP address range

If you use a public IP address range, then your devices will be reachable from the Internet. This is not necessarily a bad thing, but it does open up your devices to potential attacks.

If you use a private IP address range, then your devices will only be reachable from within your own network. This is much more secure, as it means that anyone on the Internet will not be able to directly access your devices.

There are a few different private IP address ranges that you can choose from, but the most common one is the 192.168.0.0/16 range. This is the range that most home routers use, and it’s a good choice for small networks.

For larger networks, you may want to use a different private IP address range. The 10.0.0.0/8 range is often used for this purpose.

2. Assign static IP addresses to servers and network devices

If you don’t assign static IP addresses to your devices, then every time the device reboots it will be assigned a new IP address by the DHCP server. This can cause all sorts of problems, such as breaking firewall rules, disrupting network connectivity, and so on.

It’s much easier to manage a network when all of the devices have static IP addresses. You can easily add these devices to your inventory management system, and you’ll always know what IP address they are using.

There are some exceptions to this rule, such as when you’re using mobile devices that connect to the network via WiFi. In these cases, it’s usually best to use DHCP so that the devices will be automatically assigned an IP address when they connect to the network.

3. Use DHCP reservations for other hosts

When you use DHCP reservations, the IP address of a host is permanently assigned to that host, which means that the same IP address will always be assigned to that host as long as it’s on the network. This is useful for hosts that need to be accessible by other devices on the network using their IP address (e.g. servers, printers, etc.).

Using DHCP reservations also has the added benefit of making it easier to manage your IP addresses, since you don’t have to worry about manually assigning IP addresses to hosts or keeping track of which IP addresses are assigned to which hosts.

4. Avoid using the last IP in each subnet

When a device sends a broadcast, it sends it to all devices on the same subnet. The last IP in each subnet is reserved for broadcast, so if you use that IP as a host address, your device will receive its own broadcasts and process them, which can lead to all sorts of problems.

It’s much better to use the second-to-last IP in each subnet as your host address. That way, you’ll still be able to communicate with all devices on the subnet, but you won’t have to worry about processing your own broadcasts.

5. Don’t use broadcast or multicast addresses

Broadcast addresses are used to send data packets to all devices on a network. However, this can be a security risk because it means that any malicious actor on the network can intercept and read the data packets meant for other devices.

Multicast addresses are similar to broadcast addresses, but they’re used to send data packets to a group of devices rather than all devices on a network. While this is less of a security risk than using broadcast addresses, it can still be problematic because it can lead to network congestion if too many devices are receiving the multicast data packets.

6. Use VLANs to separate different types of traffic

VLANs are virtual LANs that can be used to segment traffic on a network. By separating different types of traffic onto different VLANs, you can improve security and performance while making it easier to manage your network.

For example, you might put all of your user traffic on one VLAN and all of your server traffic on another VLAN. This would make it much harder for an attacker to sniff traffic or launch a man-in-the-middle attack, and it would also make it easier to troubleshoot problems since you wouldn’t have to worry about cross-traffic affecting your results.

Additionally, using VLANs can help improve performance by reducing congestion on your network. For example, if you have a lot of video streaming traffic, you might want to put that traffic on its own VLAN so it doesn’t slow down other types of traffic.

Overall, using VLANs is a great way to improve the security and performance of your network while making it easier to manage.

7. Use NAT when connecting multiple networks

When you have multiple networks that need to communicate with each other, it’s important to use NAT (Network Address Translation) so that each network can have its own unique IP address range. This way, there won’t be any conflicts between the addresses of the different networks.

NAT also allows you to hide the internal IP addresses of your devices from the outside world. This is important for security because it makes it more difficult for hackers to target specific devices on your network.

Finally, NAT can help improve the performance of your network by reducing the number of broadcasts that are sent. Broadcasts are packets that are sent to all devices on a network, and they can cause problems if too many of them are sent. By using NAT, you can reduce the number of broadcasts that are sent, which can improve the performance of your network.

8. Use DNS names instead of IP addresses wherever possible

DNS names are much easier for humans to remember than IP addresses. They’re also less likely to change, which means that you won’t have to go through the hassle of updating your configuration files every time there’s a change in the IP address scheme.

What’s more, using DNS names instead of IP addresses can help improve security. That’s because it’s harder for attackers to guess DNS names than IP addresses.

Finally, using DNS names instead of IP addresses can help improve performance. That’s because DNS names are cached by DNS servers, which means that they don’t have to be resolved every time they’re used.

9. Document your IP addressing scheme

If you don’t document your IP addressing scheme, then when something goes wrong (and something always goes wrong), it will be very difficult for someone else to understand what you did and why you did it. This is especially true if the person who designed the scheme is no longer with the company.

Documenting your IP addressing scheme doesn’t have to be complicated. A simple spreadsheet that lists each subnet, the network address, the broadcast address, the netmask, and a description of what each subnet is used for is usually sufficient.

If you want to get really fancy, you can create a Visio diagram that shows how all of the subnets are interconnected. But even a simple spreadsheet will go a long way towards making sure that your IP addressing scheme is understandable and maintainable.

10. Keep it simple!

A simple IP addressing scheme is much easier to understand and manage than a complex one. When you have a large network with hundreds or even thousands of devices, it can be very difficult to keep track of all the different IP addresses and subnets.

It’s also important to keep your IP addressing scheme consistent across all your devices. This will make it much easier to configure and troubleshoot networking issues.

Finally, you should avoid using private IP addresses for public-facing services. Private IP addresses are not routable on the public Internet, so anyone trying to access your website or email server will not be able to reach it.