Question: What is the relationship between Mobile IP security functionality and 3G network access security architecture?
Option 1: They are integrated and influence each other.
Option 2: They are separate and independent of each other.
Option 3: Mobile IP security functionality is a subset of 3G network access security architecture.
Option 4: 3G network access security architecture is a subset of Mobile IP security functionality.
Explanation: The correct answer is Option 2 because the text states that "The Mobile IP security functionality must thus be separate from the 3G network access security" and also mentions that they are developed in different forums (IETF for Mobile IP and 3GPP for 3G). This indicates that they are independent of each other.