Network Enumeration is the discovery of hosts/devices on a network, they tend to use overt discovery protocols such as ICMP and SNMP to gather information, they may also scan various ports on remote hosts for looking for well known services in an attempt to further identify the function of a remote host.The next stage of enumeration is to fingerprint the Operating System of the remote host.
ICMP |
In a case where a router receives a protocol data unit (PDU) larger than the next hop's MTU, it has two options if the transport is IPv4: drop the PDU and send an Internet Control Message Protocol (ICMP) message which indicates the condition Packet too Big, or fragment the IP packet and send it over the link with a smaller MTU.
he has taught privately, and became one of the first teachers at the Guitar Institute (now called The Institute of Contemporary Music Performance, ICMP).
SuperScan is a free connect-based port scanning software designed to detect open TCP and UDP ports on a target computer, determine which services are running on those ports, and run queries such as whois, ping, ICMP traceroute, and Hostname lookups.