Exam 5: Internet Control Message Protocol

Routers send ICMP Redirect messages to hosts to indicate that a preferable route exists.

Which of the following message types permit a gateway (router) on a nonoptimal route between sender and receiver to redirect traffic to a more optimal path?

The PMTU specification defined in RFC 1191 requires the PMTU host to try periodically a larger MTU to see if the ____________________ has increased.

Which of the following types of messages serves to keep hosts apprised of networking conditions and problems, and equipped to use best paths around the network?

The value 0 in the IP header Protocol field denotes that an ICMP header follows the IP header.

Two of the most well-known utilities, Ping and Traceroute, rely on ICMP to perform connectivity tests and ____________________.

Briefly describe an ICMP router discovery attack.

Match each item with a statement below. a.Network congestion b.firewalking c.ICMP query message d.inverse mapping e.ICMP Echo communication f.overhead g.reachability h.throughput difference i.restricting link -the process of identifying live network hosts positioned behind a filtering device by probing for addresses known not to be in use

Which of the following can hackers can use as part of a reconnaissance process to learn about active network addresses and active processes?

What is the purpose of the following ICMP message types: ICMP Redirect, ICMP Time Exceeded, and ICMP Parameter Problem?

Which ICMP reply does a router send in order to indicate that the router cannot use the strict or loose source routing path specified in the original packet?

Which of the following ICMP packet fields provide error detection for the ICMP header only?

Which of the following typically learn about routes through manual configuration of the default gateway parameter and redirection messages?

What protocol protects the authentication and confidentiality of ICMPv6 exchanges?

Match each item with a statement below. a.Network congestion b.firewalking c.ICMP query message d.inverse mapping e.ICMP Echo communication f.overhead g.reachability h.throughput difference i.restricting link -a condition that occurs when the delivery time for packets increases beyond normal limits

With router advertising, the default Lifetime value for route entries is 10 minutes. Indicate the answer choice that best completes the statement or answers the question.

ICMP packets contain only three required fields after the IP header: Type, Code, and Checksum.

Briefly describe the fields that are included in the ICMPv4 Router Advertisement packets (after the ICMP Checksum field).

Match each item with a statement below. a.Network congestion b.firewalking c.ICMP query message d.inverse mapping e.ICMP Echo communication f.overhead g.reachability h.throughput difference i.restricting link -an ICMP message that contains requests for configuration or other information

For any network node to communicate and exchange data with another network node, some way of forwarding packets from the sender to receiver must exist. What is this concept called?