Snort: Large number of alerts from Snort for other protocols
The Other Protocols Snort rule captures traffic such as ICMP (ping) and other normal network traffic. Do not use this rule unless there is a specific reason, and even then, use it sparingly as it will constantly generate alerts.
Network monitoring triggers this rule, as will many other forms of network traffic that are considered normal day-to-day operations.
Use the Other Protocols rule only on a network that does not use ICMP for network monitoring and is typically extremely quiet.