RPKI Security Best Practices: What, Why, and How

Resource Public Key Infrastructure (RPKI) is a cryptographic system aimed at improving the security of Internet routing by reducing the risks associated with BGP (Border Gateway Protocol) hijacking and various routing attacks. Although it possesses significant potential, the successful implementation and ongoing management of RPKI necessitate compliance with certain best practices. This article will explore the concept of RPKI, its importance, and the steps for secure implementation.

What is RPKI?

RPKI is a framework for public key infrastructure designed to enhance the security of the Internet's global routing infrastructure. It functions by enabling the authentication of the source of IP address announcements. Network operators utilize RPKI to generate digital certificates, referred to as Route Origin Authorizations (ROAs), which link designated IP address prefixes to approved Autonomous System (AS) numbers. Consequently, when a BGP router obtains an update regarding a specific IP prefix, it can confirm the legitimacy of the announcement through the data supplied by RPKI.

Why is RPKI Important?

The routing infrastructure of the Internet is predominantly dependent on BGP, which was initially developed with minimal emphasis on security considerations. Consequently, it is susceptible to a range of attacks, including BGP hijacking and route leaks. In instances of BGP hijacking, an attacker may falsely declare ownership of IP prefixes, redirecting traffic to their own network for malicious intents such as traffic interception, eavesdropping, or service disruptions.

RPKI serves as a protective measure against these types of attacks by ensuring that only authorized Autonomous Systems (ASes) are permitted to announce designated IP prefixes. By employing RPKI to validate BGP announcements, network operators can substantially mitigate the likelihood of routing incidents, thereby improving the overall stability and security of the Internet. The implementation of RPKI is thus essential for safeguarding against both routing misconfigurations and intentional attacks that threaten network integrity.

How to Implement RPKI Security Best Practices

The successful implementation of RPKI requires a series of steps and continuous maintenance to guarantee maximum security. Below are several best practices to adhere to:

1. Create and Regularly Update ROAs

The first step in securing your network with RPKI is to create Route Origin Authorizations (ROAs) for your IP prefixes. A ROA specifies which AS is authorized to announce a given prefix, allowing routers to validate incoming BGP updates. However, creating a ROA is not a one-time task; it requires regular updates.

Best Practice:

• Keep your ROAs up to date. If you reassign an IP prefix or change the AS number associated with it, make sure to update the corresponding ROA. Outdated ROAs can lead to legitimate traffic being marked as invalid, potentially causing service disruptions.

2. Enable RPKI Validation on Routers

Configuring your BGP routers to perform RPKI validation is essential for filtering out invalid routes. When a router receives a BGP announcement, it checks the ROA to determine whether the announcement is valid, invalid, or unknown. Based on this validation, the router can then decide how to handle the route.

Best Practice:

• Set your routers to reject invalid routes. This helps prevent malicious or misconfigured announcements from entering your network. At a minimum, you should deprioritize invalid routes to reduce the risk of routing issues.

3. Monitor RPKI Validation and Alerts

Monitoring your network for RPKI validation status and alerts is crucial for detecting potential issues early. By keeping an eye on validation errors and anomalies, you can respond quickly to changes that might indicate a misconfiguration or a hijacking attempt.

Best Practice:

• Use RPKI validation software such as Routinator, GoRTR, or RPKI Validator to continuously check the validity of BGP announcements. Set up alerts to notify you if a valid route becomes invalid, as this could signal a configuration change or an attempt at route hijacking.

4. Implement Robust Key Management Practices

The security of RPKI relies on the integrity of its cryptographic keys. If these keys are compromised, attackers could create fraudulent ROAs, leading to incorrect routing decisions.

Best Practice:

• Store your cryptographic keys securely and implement multi-factor authentication (MFA) for key access. Regularly rotate keys to minimize the risk of unauthorized use.

5. Use ROV (Route Origin Validation) Policies

Route Origin Validation (ROV) is a process where routers validate the origin of IP prefixes against the ROAs in the RPKI repository. Setting clear ROV policies helps in maintaining secure routing.

Best Practice:

• Implement a strict ROV policy where your routers prioritize routes based on their validation status. For example, set routes with a "valid" status as preferred, while deprioritizing or rejecting "invalid" routes.

Conclusion

RPKI serves as a robust mechanism that adds a crucial layer of security to the routing framework of the Internet. By adhering to RPKI best practices, including the establishment of precise Route Origin Authorizations (ROAs), the activation of route validation, and the implementation of rigorous key management, network operators can markedly diminish the likelihood of BGP hijacking and routing leaks. As the adoption of RPKI expands among networks, the overall security and stability of global Internet routing will enhance, safeguarding users from potential threats and fostering greater trust in the Internet's infrastructure.

By implementing these best practices, you not only contribute to a more secure Internet but also gain the advantages of enhanced security and reliability for your network.