LTE stands for Long Term Evolution. It is the evolved version of already present cellular network architecture. In general term people call it 4G also. But in fact it is NOT a 4G technology standard, it's a 3.9G. LTE-Advance is the actual 4G technology standard. Before going further in to the brain storming architecture and call flows, we should first know the history and evolution of LTE to keep interest in it. So the evolution of a cellular network is as follows in the diagram. As I am too lazy to draw a complete diagram, I have pulled an image of Rohde & Scewarz : [ Click on the image for zoom ] So, There are several organizations who work for cellular network architect such as 3GPP, 3GPP2, IEEE. LTE standard is defined by 3GPP. So anything you read, implement or use for LTE, it should be as per 3GPP standards. As we are going forward day by day, we see that there are more data hungry applications. LTE will resolve this issue. In the next post we will r