I'm struggling to understand the following: When I send
sudo nping --icmp 10.10.10.10 --icmp-type 8 --icmp-id 12345 -v4
I notice the my request actually sets the id to 12345
echo request (type=8/code=0) id=12345 seq=1
However, if I change the type to 15
sudo nping --icmp 10.10.10.10 --icmp-type 15 --icmp-id 12345 -v4
my request is as follows:
echo request (type=15/code=0) id=0 seq=1
I understand that type 15 is deprecated according to IANA however using type 15 and constructing a request with a data string, gives me a reply from the destination that indicates I need to set the ID.
sudo nping --icmp 10.10.10.10 --icmp-type 15 --icmp-id 12345 -v4
Gives a reply message of "You need to set the ID to 12345 for more information"
Any deeper insights would be welcomed as I can't see it possible to use any other combination of types with an ID.