Ch 5 CIT 372

The ICMP header contains a variety of fields. The Type field identifies the types of ICMP messages that can be sent on the network. Of the following, which value in the Type field would indicate an Echo Reply?

0

There are a variety of ICMPv6 message types that are indicated by a numeric value. Of the following, which value indicates Destination Unreachable?

1

For the ICMPv6 error message Destination Unreachable, in the Code field, which value indicates Address unreachable?

3

ICMP or Internet Control Message Protocol is an important Network layer protocol because it provides information about network connectivity and routing behavior. Of the following, which is the correct ICMP message type and description? (choose all that apply.)

Echo/Echo Reply supports functionality for reachability utilities like Ping and Tracert. Router Advertisement permits hosts to request information about local routers and lets routers advertise their existence on IP networks. Parameter Problem indicates some error has occurred while processing the IP header of an incoming datagram

ICMP or Internet Control Message Protocol is an important Network layer protocol because, along with IP and UDP, it provides information about network connectivity and routing behavior.

False

ICMPv6 Router Solicitation and Router Advertisement messages function in the same way as the ICMPv4 versions of these messages. Router discovery in IPv6 works similarly to the same function in IPv4 except for what?

The Router Discovery function as been integrated into the Neighbor Discovery (ND) protocol.

Sending a Traceroute message as a single packet is experimental.

True

The ICMP header contains a variety of fields. The Code field can contain a variety of values that are used with ICMP Destination Unreachable packets. If a Code field contains the value 1, it indicates Host Unreachable.

True

Which of the following, which is included in the general format of an ICMPv6 message header? (Choose all that apply.)

Type Code Checksum

The ICMPv4 message type Time Exceeded is sent in two circumstances. Of the following, which are the correct descriptions of those circumstances? (choose two.)

When a packet's Time to Live (TTL) field is decremented to zero by routers on the network before the packet reaches its destination. When some of the fragments of a message do not reach the destination by the time the node's reassembly timer reaches zero.

Which general message types are shared between ICMPv4 and ICMPv6? (choose three.)

Error-checking messages Fragmentation required messages Informational messages

Of the following, which are security features built in to ICMPv6?

Authentication for ICMPv6 header exchanges is handled by the IP Authentication Header (IPv6-AUTH) or the IP Encapsulating Security Payload Header (IPv6-ESP). The value in the Hop Limit field is set to 255. The source address of ICMPv6 packets must be either link-local or unspecified (::/128

The ICMPv4 message type Timestamp Request and Timestamp Reply is used on a network to synchronize system clocks for date and time so that devices on the network can work together without timing errors. Which network device is responsible for using these pair of messages to synchronize network system clocks?

routers