Which of the following tools can be used to sniff usernames and passwords using Firefox?

The Iterator interface

A) is defined in the java.awt package B) is defined in the javax.swing package C) has next(), isEmpty(), and retrieve() methods D) has next(), hasNext(), and remove() methods

IPsec provides security services at the ________ layer by enabling a system to select required security protocols, determine the algorithms to use for the services and put in place any cryptographic keys required to provide the requested services.

Fill in the blank(s) with the appropriate word(s).