Encryption

Review Questions

You can find the solutions to these questions in Appendix A, "Answers to Review Questions."

1.	Which of the following are not security threats to an IP telephony system? (Choose two.) Loss of privacy Impersonation Integrity Loss of integrity Loss of control DoS
2.	Which of the following represent correct mappings of applicationprotocolsecurity features? (Choose two.) Secure signalingSRTPdevice authentication, integrity Secure signalingTLSdevice authentication, integrity, privacy Secure mediaSRTPprivacy, confidentiality, security Secure mediaTLSprivacy, confidentiality, security Secure mediaTLSprivacy, integrity Secure mediaSRTPprivacy, integrity
3.	Which two statements about trusted introducing are incorrect? The trusted introducer has to be trusted by all other members of the system. The trusted introducer has to trust all other members of the system. The trusted introducer guarantees the authenticity of entities it is introducing to others. Only the trusted introducer has to trust the root of the system. The trusted introducer is the root of a system. Any entity of the system can guarantee the authenticity of any other member.
4.	Which two statements about PKI topologies in Cisco IP telephony are true? MICs are self-signed by the IP phone. Cisco IP Phone 7940, 7960, and 7970 models can have MICs and LSCs. The CAPF has a self-signed certificate. Only Cisco IP Phone 7940, 7960, and 7970 (and subsequent) models can have LSCs. The CTL is signed by the Cisco manufacturing CA. MICs are signed by CAPF.
5.	Which are the two valid options to secure enrollment in a PKI? Perform the enrollment from a trusted device only. Perform the enrollment in both directions. Perform the enrollment over a trusted network. Use self-signed certificates on all devices. Do not send the private key in the enrollment. Perform mutual out-of-band authentication between the PKI user and CA.
6.	Which statement about enrollment in the IP telephony PKI is true? MICs are issued by CAPF itself or by an external CA. LSCs are issued by the Cisco CTL client or by CAPF. CAPF enrollment supports the use of authentication strings. CAPF itself has to enroll with the Cisco CTL client. Enrollment of IP phones occurs automatically if the cluster is in secure-only mode. LSCs can be issued by an external CA when using the CTL client as a proxy.
7.	Which of the following entities uses a smart token for key storage? CTL CTL client CAPF in proxy mode CAPF in CA mode Cisco IP Phone 7940 and 7960 Cisco IP Phone 7970
8.	What are the authentication features of TLS in Cisco IP telephony? Two-way device authentication Two-way device authentication and signed media messages One-way device authentication and signed signaling message Two-way device authentication and signed signaling messages One-way device authentication and signed media messages Signed signaling messages
9.	During an encrypted call between two IP phones, which two of the following does not happen? Mutual certificate exchange between Cisco CallManager and each IP phone Mutual certificate exchange between the IP phones SRTP packet authentication and encryption Encrypted transmission of SRTP session keys between the IP phones TLS packet authentication and encryption Encrypted transmission of TLS session keys between Cisco CallManager and the IP phones
10.	Which is the most accurate list of tasks required to configure a Cisco CallManager cluster for security? Enable services, set cluster to mixed mode, create a signed CTL, and deploy certificates to the IP phones. Enable services, set cluster to secure-only mode, create a signed CTL, and deploy certificates to the IP phones. Enable extended services, set cluster to authenticated or encrypted mode, create a signed CTL, and deploy certificates to the IP phones. Disable extended services, set cluster to mixed mode, create a signed CTL, and deploy certificates to the IP phones. Enable services, set cluster to mixed mode, create a signed CTL, deploy certificates to the IP phones, and set the device security mode. Run the auto-secure feature.