Many network providers lock phones to their network and sell them at low cost. When users buy such phones they need to stay with that network till the contract ends. In this way the network provider increases their potential. Incase a user needs to unlock their phone in the middle of contract they can request their respective network provider. If they deny there are many free online unlocking vendors like Unlock-free.com where they unlock basic mobile models. I am not sure about the cable thingy as it is new to me.