When purchased, the SIM is registered by a network, the details are
stored in the home network (HLR or HSS) with other details that allow the SIM
to run on the network.
The SIM is inserted in the mobile station (MS) and powered up.
The MS connects to the local network and is now available to be used
subject to the constraints of the SIM, largely financial constraints.
The wireless element is the connection between the mobile phone and the
mast. The communications within the rest of the network, the backhaul,
is most likely fibre optic cable.
Whilst switched on and a network is available, the mobile is tracked
and if necessary the control passed from one base station element to another
through a process called handover
Mobile phones are often called cell phones. A cell is the area which is
controlled by a single mast often represented by a hexhagonal cell
A MS will be able to make or receive a call, send or receive a text,
send or receive data.
The trunk or backhaul network must have the capacity to deal with all the
connections made to the mast or core network within a time with acceptable
lag.