The VoIP administrator starts receiving reports that users are having problems placing phone
calls. The VoIP administrator cannot determine the issue, and asks the security administrator for
help. The security administrator reviews the switch interfaces and does not see an excessive
amount of network traffic on the voice network. Using a protocol analyzer, the security
administrator does see an excessive number of SIP INVITE packets destined for the SIP proxy.
Based on the information given, which of the following types of attacks is underway and how can it
be remediated?
A.
Man in the middle attack; install an IPS in front of SIP proxy.
B.
Man in the middle attack; use 802.1x to secure voice VLAN.
C.
Denial of Service; switch to more secure H.323 protocol.
D.
Denial of Service; use rate limiting to limit traffic.