Your employer's security policies state that all externally facing servers should only be accessible via ports that are absolutely required. Generally your company only has web servers that are accessible from outside the companies network. A recent security review showed that it was possible to ping several of these web servers. What protocol should be disabled using a firewall to ensure pings do not successfully contact the servers?
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Network diagnostic tools like ping and tracert use the Internet Control Message Protocol (ICMP) to function. Using a firewall to block external systems from using this protocol to contact internal solutions will ensure ping cannot be used against the servers discussed in the question.
Wikipedia
The Internet Control Message Protocol (ICMP) is a supporting protocol in the Internet protocol suite. It is used by network devices, including routers, to send error messages and operational information indicating success or failure when communicating with another IP address, for example, an error is indicated when a requested service is not available or that a host or router could not be reached. ICMP differs from transport protocols such as TCP and UDP in that it is not typically used to exchange data between systems, nor is it regularly employed by end-user network applications (with the exception of some diagnostic tools like ping and traceroute).
ICMP for IPv4 is defined in RFC 792. A separate ICMPv6, defined by RFC 4443, is used with IPv6.
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