PCNSE Exam Dumps : Palo Alto Networks Certified Security Engineer (PCNSE) PAN-OS 11.0

For virtual systems (vSys) on a Palo Alto Networks firewall to communicate with each other, especially when separate virtual routers (VRs) are used for each vSys, the configuration must facilitate proper routing and security policy enforcement. The key aspects to focus on include:

A. External zones with the virtual systems added:

External zones are special types of zones that are used to facilitate traffic flow between virtual systems within the same physical firewall. By adding virtual systems to an external zone, you enable them to communicate with each other, effectively bypassing the need for traffic to exit and re-enter the firewall.

D. Add a route with next hop next-vr by using the VR configured in the virtual system:

When using separate VRs for each vSys, it's essential to configure inter-VR routing. This is done by adding routes in each VR with the next hop set to 'next-vr', specifying the VR of the destination vSys. This setup enables traffic to be routed from one virtual system's VR to another, facilitating communication between them.

E. Ensure the virtual systems are visible to one another:

Visibility between virtual systems is a prerequisite for inter-vSys communication. This involves configuring the virtual systems in a way that they are aware of each other's existence. This is typically managed in the vSys settings, where you can specify which virtual systems can communicate with each other.

By focusing on these configuration details, the network security engineer can ensure that the virtual systems can communicate effectively, maintaining the necessary isolation while allowing the required traffic flow.

When sizing a decryption firewall deployment, two factors that should be considered are the encryption algorithm and the TLS protocol version. These factors affect the amount of resources and processing power that the firewall needs to decrypt and inspect SSL/TLS traffic.

The encryption algorithm is the method that the server and the client use to encrypt and decrypt the data exchanged in an SSL/TLS session. Different encryption algorithms have different levels of security and performance. For example, AES is a symmetric encryption algorithm that is faster and more efficient than RSA, which is an asymmetric encryption algorithm. However, RSA is more secure than AES because it uses public and private keys to encrypt and decrypt data, while AES uses a single shared key. The firewall must support the encryption algorithms that are used by the servers and clients that it decrypts, and it must have enough CPU and memory resources to handle the decryption workload12.

The TLS protocol version is the standard that defines how the server and the client establish and maintain an SSL/TLS session. Different TLS protocol versions have different features and requirements for encryption algorithms, cipher suites, certificates, handshake messages, etc. For example, TLS 1.3 is the latest and most secure version of TLS, which supports only strong encryption algorithms and cipher suites, such as AES-GCM and ChaCha20-Poly1305, and requires elliptic curve certificates. The firewall must support the TLS protocol versions that are used by the servers and clients that it decrypts, and it must have enough hardware acceleration resources to handle the decryption speed34.

The number of security zones in decryption policies and the number of blocked sessions are not relevant factors for sizing a decryption firewall deployment. The number of security zones in decryption policies only affects how the firewall matches traffic to decryption rules based on source and destination zones, but it does not affect the decryption performance or resource consumption. The number of blocked sessions only indicates how many sessions are denied by the firewall based on security policy or decryption policy rules, but it does not affect the decryption capacity or throughput56.

 Encryption Algorithms, TLS Protocol Versions, Decryption Policy, PCNSE Study Guide (page 60)