1. Pertemuan 18 TCP/IP Suite Control Messages

2. Discussion Topics Introduction to control messages
CMP redirect/change requests
Clock synchronization and transit time estimation
Information requests and reply message formats
Address mask requirements
Router discovery message
Router solicitation message
Congestion and flow control messages

3. ICMP Redirect/Change Requests
The default gateway of the host may need to use a redirect/change request to inform the host of the best path to a certain network.

4. Clock Synchronization and Transit Time Estimation
The ICMP timestamp request message allows a host to ask for the current time according to the remote host.
The remote host uses an ICMP timestamp reply message to respond to the request.

5. Address Mask Requirements
When a network administrator uses the process of subnetting to divide a major IP address into multiple subnets, a new subnet mask is created.

6. Router Discovery Message
When a host on the network boots, and the host has not been manually configured with a default gateway, it can learn of available routers through the process of router discovery.

7. Router Solicitation Message
A host generates an ICMP router solicitation message in response to a missing default gateway.

8. Congestion and Flow Control Messages
ICMP source-quench messages are used to reduce the amount of data lost from congestion.