1. A method of validating a message received at a network component, the method comprising the steps of: receiving a message at the network component; selecting a validation scenario applicable to the message from a set of validation scenarios; determining a set of validation conditions associated with the determined validation scenario; for each validation condition of the set of validation conditions: determining whether the message passes the validation condition, and if the message does not pass the validation condition, determining that the message is invalid; and if the message passes each validation condition, determining that the message is valid.