What is an Echo Request message?
The ICMP Echo Request query message is a probe sent by a user to a destination system, which responds with an ICMP Echo Reply query message. ping works by sending one or more ICMP Echo Request messages to a destination system, and then measuring the amount of time it took for the ICMP Echo Reply …
What is the code type for Echo Request?
ICMP Echo request and reply The ICMP echo reply is a type 0 and code 0 message.
What is the ICMPv6 echo message type?
Type: Identifies the ICMPv6 message type; for Echo Request messages the value is 128, and for Echo Reply messages 129. (Recall that in ICMPv6, informational messages always have a Type value of 128 or higher.) If this is sent in the Echo Request it is copied into the Echo Reply to be sent back to the source.
How do I send a packet request echo?
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 commands do ICMP report?
ICMP errors are directed to the source IP address of the originating packet. The traceroute command can be implemented by transmitting IP datagrams with specially set IP TTL header fields, and looking for ICMP time exceeded in transit and Destination unreachable messages generated in response.
What is ICMP echo message?
Internet Control Message Protocol (ICMP) is one of the protocols of the TCP/IP suite. 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 does ICMP type 3 code 13 mean?
An ICMP type 3, code 13 response means that the machine is down.
What are the ICMP message types?
Internet Control Message Protocol (ICMP) Parameters
- Type 0 — Echo Reply.
- Type 1 — Unassigned.
- Type 2 — Unassigned.
- Type 3 — Destination Unreachable.
- Type 4 — Source Quench (Deprecated)
- Type 5 — Redirect.
- Type 6 — Alternate Host Address (Deprecated)
- Type 7 — Unassigned.
What is the difference between ICMPv4 and ICMPv6?
ICMPv4 is the messaging protocol for IPv4. ICMPv6 provides these same services for IPv6 but includes additional functionality. In this course, the term ICMP will be used when referring to both ICMPv4 and ICMPv6.
What are two ICMPv6 messages that are?
IPv6 uses neighbor solicitation (NS) and neighbor advertisement (NA) ICMPv6 messages for MAC address resolution.
What is the size of ICMP header?
8-byte
The ICMP header starts after the IPv4 header and is identified by IP protocol number ‘1’. All ICMP packets have an 8-byte header and variable-sized data section. The first 4 bytes of the header have fixed format, while the last 4 bytes depend on the type/code of that ICMP packet.
Is ping An ICMP message?
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.