you are likely to find Hat in/at/on Head. Head is related to Big. Big is related to College. 
Protocol is a type of Rule. Rule is related to Requirement. Requirement is related to Essential. Essential is related to Oxygen. 
Hat --AtLocation--> Head <--RelatedTo--> Big <--RelatedTo--> College 
Protocol --IsA--> Rule <--RelatedTo--> Requirement <--RelatedTo--> Essential <--RelatedTo--> Oxygen 