CompTIA CASP+ Practice Test

What method should a security researcher apply to identify active ports and protocols on a VoIP routing appliance?

1. Static code analysis

2. Network traffic analysis

3. Device fingerprinting

4. Packet capture

The correct answer is: Device fingerprinting

The correct method for identifying active ports and protocols on a VoIP routing appliance is through device fingerprinting. Device fingerprinting involves gathering information about a device's characteristics and behavior over the network. This can include identifying the operating system, hardware, and services running on that device based on response patterns to probe packets or other network interactions. By employing device fingerprinting, a security researcher can analyze the responses from the VoIP routing appliance to determine which ports are open and what protocols are in use. This method is particularly effective because it provides insights into how the device behaves on the network, thus revealing its active services. Other options, while relevant in the context of network security, do not specifically target the identification of open ports and protocols in the same direct manner. Network traffic analysis focuses on monitoring data flows to and from the device, which might reveal which ports are being communicated with but does not actively probe the device itself. Static code analysis would involve examining source code to find vulnerabilities before the software is deployed and is not applicable for identifying live network characteristics. Packet capture refers to the technique of intercepting and logging traffic over the network, which also may not specifically identify the protocol services without further contextual processing.