Your mobile phone will be having sim card and that is associated with respective mobile service provider (msp). Due to some reason you wish to switch from current msp to some other msp then Mobile IP is used to to migrate from one network to another. Mobile IP has to two part they are
- Care-of-address (CoA)
- Second is home address
When you go for Mobile number portability then the home address will be shifted to new mobile service provider.
Navilu 