ICMP Quiz

What is the header size of ICMP Packet?

• 8 Bytes

• 10 Bytes

• 6 Bytes

• 12 Bytes

Which port number does ICMP use?

• Port 80

• None

•  Port 17

• ICMP does not use any port number as it does not use any transport layer protocols.

Which two fields in the ICMP header is used for identifying the intent of ICMP message?

• Type and Code

• MPLS

• Type and IPS

• None

What statement is true regarding ICMP packets?

•  They acknowledge receipt of TCP segments.

• They are encapsulated within UDP datagrams.

• They guarantee datagram delivery.

• They can provide hosts with information about network problems & are encapsulated within IP datagrams.

For security reasons, the Cisco network administrator needs to prevent pings into the corporate networks from hosts outside the internetwork. Using access control lists, which protocol should be blocked?

• TCP

• NONE

• UDP

• ICMP

You execute the ping command from a host, but the router does not have a path to its destination. Which of the following ICMP message types will a client receive from the router?

• ICMP destination unreachable

• ICMP echo-reply

• ICMP time exceeded.

• ICMP redirect

In Windows, ____________ can be used to trace the route of the packet from the source to the destination.

• traceroute

• tracert

• ping

•  locater

During error reporting, ICMP always reports error messages to ________

• 
  
  Destination

• Source

• Next router
  
  

• Previous router.

ICMP error message will not be generated for a datagram having a special address such as _______

• 127.0.0.0
  

• 12.1.2.0
  

• 11.1.0.0
  

• 127.0.0

In case of time exceeded error, when the datagram visits a router, the value of time to live field is

• Remains constant
  

• Decremented by 2
  

• Incremented by 1
  

• Decremented by 1