Comment by miki123211

"From GSM to LTE–Advanced Pro and 5G, An Introduction to Mobile Networks and Mobile Broadband" by Martin Sauter

This is the telecoms book I never knew I wanted. As the title suggests, it explains how the telecom world has evolved in great detail, with a particular focus on mobile technologies, although there's a chapter on SS7 and one on WiFi and Bluetooth. It stops short of packet layout descriptions, but it goes extremely deeply into the technologies it describes while still being understandable to somebody with little to no telecoms experience. This is the book that made me truly understand how that stuff really works.