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What layer protocol is ICMP?
layer 3 protocol
Networking on z/OS Therefore, in the topic on TCP/IP-based layered network, ICMP is shown as a layer 3 protocol. ICMP is probably most well known as the message protocol used for the ping command. A ping command sends an ICMP echo request to the target host. The target host responds with an echo reply.
How do I send an echo ICMP?
To send an ICMP echo request packet to the IP address that you specify: Issue the ping command in Privileged Exec mode….The following characters can appear in the display after issuing the ping command:
- !
- .
- ?
- A—Address mask request message.
- a—Address mask reply message.
- D—Router discovery advertisement message.
What is the ICMP type for the echo reply packets?
Echo Reply (0), Echo Request (8), Redirect (5), Destination Unreachable (3), Traceroute (30), Time Exceeded (11). Many of these ICMP types have a “code” field.
What is ICMP code for echo request?
Table 3.2 ICMP Message Types
| Type | Description ICMP Message Types |
|---|---|
| 8 | Echo Request (Ping Request, used with Type 0, Ping Reply) |
| 9 | Router Advertisement (Used with Type 9) |
| 10 | Router Solicitation (Used with Type 10) |
| 11 | Time Exceeded |
What is echo request and echo reply in ICMP?
The ICMP echo request and the ICMP echo reply messages are commonly known as ping messages. The ping command sends an ICMP echo request to a device on the network, and the device immediately responds with an ICMP echo reply.
What is the ICMP type code number?
Identifying default ICMP types
| ICMP Type | Message |
|---|---|
| 0 | Echo reply |
| 3 | Destination unreachable |
| 4 | Source quench |
| 5 | Redirect |
How is an ICMP echo request used in DHCP?
An ICMP Echo request from the DHCP server to the IP address its about to allocate is used to determine if the IP address about to be assigned is already in use on the network. If a response is received from that IP the DHCP server will assign a different address.
How does Internet Control Message protocol ( ICMP ) work?
ICMP will take source IP from the discarded packet and informs to source by sending source quench message. Then source will reduce the speed of transmission so that router will free for congestion.
When does ICMP send a Time Exceeded message?
When some fragments are lost in a network then the holding fragment by the router will be dropped then ICMP will take source IP from discarded packet and informs to the source, of discarded datagram due to time to live field reaches to zero, by sending time exceeded message.
What does ICMP do if there is a mismatch packet?
If there is mismatch packet will be dropped by the router. ICMP will take the source IP from the discarded packet and informs to source by sending parameter problem message.