Network security

What is IP allowlisting (whitelisting)? Understanding the basics and beyond


What is IP whitelisting?

Cloud service providers don’t magically make locally-based data infrastructure issues disappear. While it helps to achieve greater flexibility under a distributed model, your data doesn’t become more secure because it is not hosted in your building. Decentralization brings its share of risks threatening unsecured networks.

Whereas previously, only on-premise employees could access applications and software through the local network, remote and hybrid work models changed the paradigm. Businesses must be certain that remote connections are secure to be allowed to connect. This is where IP whitelisting or allowlisting comes into play (while both terms are interchangeable, allowlist is strongly favored over IP whitelist due to being a more race and culture-neutral option).

Let’s delve further into IP allowlisting/IP whitelisting and learn more about its application across organizations.

Key takeaways:

  • IP allowlisting (also called IP whitelisting) allows only predefined IP addresses and ranges to connect to networks and access resources, blocking all others. This limits access and helps control threats.
  • Benefits of IP allowlisting (whitelisting) include improved cloud and network security, enabling secure remote access, and improving productivity by blocking potentially harmful connections.
  • Challenges of IP whitelisting include being difficult to scale for large networks, not accounting for IP spoofing, issues with dynamic IPs, and potentially blocking legitimate connections. 
  • IP allowlisting (whitelisting) is generally more secure than blocklisting as it defaults to blocking all instead of specifically identifying threats, but both approaches can be combined for best security.
  • NordLayer helps enforce IP allowlisting by assigning static IPs through its Virtual Private Gateways to control cloud app access according to security policies.

What is an IP address?

At the core of any network communication is the IP address. Often overlooked but critically important, an IP address serves as the unique digital identifier for any device connected to the internet or a private network. It acts as the address that allows packets of data to be properly routed to the correct destination. 

Think of it like a physical street address—without the right number, mail carriers and deliveries would never find your home. For online systems, an IP ensures data finds its intended target whether it's traveling to a website, database, or other resource.

IP addresses can be dedicated (fixed) or shared (dynamic). Dedicated IPs tend to work best for purposes like IP allowlisting since dynamic addresses provided by ISPs can periodically change.

IP allowlisting — what is it?

IP allowlisting or IP whitelisting is a method to allow direct access into your network by bypassing firewall blocks. This feature limits system access to only a set number of IP addresses, denying all others that aren’t from the list. It helps network administrators control remote access to an organization’s network more precisely.

This solution allows setting permissions to access specific data or applications enforcing Zero Trust policies. Serving as an important qualitative improvement, IP allowlisting (whitelisting) contributes a significant leap to optimal cloud security.

IP whitelisting for Google Cloud, Amazon AWS, Salesforce, Azure

How does IP allowlisting work?

A whitelist is made by a network administrator who indicates which IP addresses or IP ranges are allowed to connect to internal networks or resources. It aims to uphold security policy by limiting exposure on the public internet — the more connections are allowed, the greater the risk of cyberattack. This approach blocks unauthorized IP address ranges, instantly shutting down potential threats. 

How IP whitelisting works

The list of allowed IP addresses heavily relies on dedicated static IP addresses to be assigned to specific organizations and groups of users. Such unique identifiers become the sole members to be allowed to connect, keeping network segmentation boundaries.

This setup works for systems inside Local Area Networks and cloud operations. Various other additions, like VPN gateways, can require additional authentication. Not having an allowed IP address means that the connection is impossible.

Benefits of IP allowlisting for business

Using IP allowlisting (whitelisting), administrators can compile a list of allowed sources that can interact with the business network. Not only does this cleans up private network connections, but it has several very important benefits.

Cloud security improvements. IP allowlisting (whitelisting) contributes as a barrier to unauthorized access to your network, which improves overall system security.

Improves productivity. IP allowlisting (whitelisting) serves as an effective and simple method to shut down the majority of incoming potentially dangerous connections supporting business continuity as well as productivity.

Secure network access. IP allowlisting (whitelisting) enables companies to set up secure remote access solutions allowing employees to work from home or anywhere else.

In general, IP allowlisting for business promotes security and workforce efficiency providing a simple method to reorganize how an organization can be reached from the outside.

IP allowlisting (whitelisting) challenges

IP allowlisting (whitelisting) can contribute to a workplace, but it has its fair share of challenges. Here are the major pain points you should consider before fully committing to this mode of operation.

Best suited to smaller networks

The process of IP allowlisting (whitelisting) directly correlates to the size of the network. The bigger the network, the harder it is to maintain the whitelist, which means unapproved connections can slip by. This means that IP allowlisting (whitelisting) is best suited to smaller organizations with fewer incoming connections and packets from various sources. Otherwise, internal segmentation is needed to group users according to their IP  packets’ source addresses. 

Doesn’t factor in IP addresses sources

An IP address is something that hackers can spoof. They can find what IP addresses are allowed and duplicate them to gain entry into the network. This means that it bypasses whitelist checks as it doesn’t verify whether its source belongs to a trusted individual. For this reason, organizations must introduce additional precautions like two-factor authentication, device ID checks, etc., to secure against spoofing attempts. 

Doesn’t work with dynamic IP addresses

The internet service providers rotate some IP addresses — therefore, they’re constantly changing. In such cases, it’s impossible to set up an IP address allowlisting (whitelisting) because the address can be later reassigned to someone else, who could gain unrestricted entry into the organization’s network. It’s also impractical to contact network administrators every session to require manually changing their IP address entry every new session.

Introduces access roadblocks

The problem with IP allowlisting (whitelisting) is that it applies not only to the connections you’d like to avoid but also to those from your own team. In cases when there is a technical emergency and additional addresses can’t be added, IP allowlisting (whitelisting) may end up stopping teammates from attempting to establish a link. This requires a solid emergency scenario on how the resource access could be restored without compromising security. 

Use cases of IP allowlisting in business

As companies scale, more control mechanisms are needed to contain various threats, especially when remote access is allowed. IP allowlisting (whitelisting) allows for addressing these problems. Here’s what are its main use cases.

Network access control

IP allowlisting (whitelisting) is often used to maintain employee access privileges and prevent unauthorized connections. A firewall is commonly used for this reason, where only whitelisted IP addresses are allowed to connect. Static IPs must remain valid indefinitely as they allow this model to function.

SaaS user management

Businesses must ensure that their employees’ access to SaaS apps is secure. Trusting SaaS providers to take care of everything blindly can be dangerous. For this reason, IP allowlisting (whitelisting) helps to manage cloud risks within the provided access framework.

Remote work enablement

The main requirement for remote employees is ensuring the connection is secure. IP allowlisting (whitelisting) indicates which connections are the only ones allowed to connect. This enables network administrators to shrink the attack surface by limiting the number of permitted connections. Often, various VPN services are used to allow only the IP addresses of users connected to the server.

IoT security

Connected IoT devices are especially challenging to secure due to their limited processing power and capabilities. This means that other cybersecurity solutions have to be configured around them. IP allowlisting (whitelisting) can restrict communication channels, ensuring that the device can be reached only by trusted entities.

Unifying access control policy

IP allowlisting (whitelisting) can form a basis for additional security methods that could be joined to create a multi-layered access control. Features like two-factor authentication or single sign-on can be added to a VPN gateway with a whitelisted IP address to access internal company networks.

Allowlisting vs blocklisting 

Access control is one of the critical areas for businesses’ cybersecurity as the first line of defense against security threats. The two main approaches to access control are allowlisting and blocklisting.

Allowlisting — access control approach in which only pre-approved applications and processes are allowed to run. This means that only singled-out IP addresses can connect or only greenlit software can be launched. Everything else is restricted.

Blocklisting — an access control strategy to block everything identified as malicious. The main problem with it is that identification of malicious materials can depend on a variety of factors. Though, blacklists can be pretty extensive and confirm what devices or their traits could be refused connection.

Allowlisting vs. blacklisting debate shows two opposites of the access management spectrum. One, by default, blocks everything but allows select connections, while the other blocks only what needs to be blocked.

Is blocklisting more secure than allowlisting (whitelisting)?

While on the surface, it would seem that allowlisting is more secure due to blocking everything but the allowed connection, the real answer is “it depends”. Allowlisting is much closer to the Zero Trust approach than blocklisting, which makes it more restrictive. However, it depends on the particular allow list — it’s very loosely defined and could have more gaps than a detailed blocklist. Finally, let’s not forget that both approaches can be combined, i.e., when creating multiple layers of security checks and simultaneously integrating them.

How to start allowlisting (whitelisting) in NordLayer?

NordLayer easily integrates into cloud applications and services, adapting to your existing infrastructure, whatever its model. With a Secure Web Gateways system, NordLayer allows users to change a connected user’s IP address to enforce strict access policies. It gives visibility and control over all employee cloud activity via a centralized Control Panel.

Additional features like single sign-on can be enabled to limit employee access further. No additional hardware or investments are needed. NordLayer allows organizations to grow without the shackles of a traditional manual setup.

Here you can find detailed information how to IP allowlist (whitelist) in:

How to start allowlisting (whitelisting) cloud applications in NordLayer?

NordLayer’s Virtual Private Gateway and IP allowlisting (whitelisting) enable you to control access to your SaaS applications and enforce additional security features. 

  1. To access Virtual Private Gateway, you’ll need to acquire an Advanced NordLayer subscription to set up your organization
  2. Virtual Private Gateways need to be set up, adding teams and assigning servers to them
  3. NordLayer needs to be allowlisted (whitelisted) in your used SaaS apps, making it the sole allowed source to connect
  4. Once users download and install NordLayer software when connected to Virtual Private Gateways, they’ll be able to access cloud resources securely with a static IP address

This method reduces the surface area for cyber attacks and granulates access to pre-approved resources. This will not only prevent potentially harmful data breaches from unauthorized users but also give you and your customers peace of mind.


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