Why was the transition from analog (1G) to digital (2G/GSM) mobile networks so significant?

Digital transmission enabled encryption, error correction, efficient multiplexing, and data services — none of which were possible with analog 1G networks.

Advantages of digital over analog:

• Encryption — analog calls could be eavesdropped with a simple radio scanner; GSM encrypts the air interface
• Error correction — digital signals can include redundancy bits to detect and correct transmission errors
• Efficient spectrum use — TDMA allows multiple users to share one frequency channel by taking turns in time slots
• Data services — SMS, and later GPRS for packet data, are fundamentally digital concepts
• Compression — voice can be digitally compressed to use less bandwidth
• Consistent quality — digital is either decodable or not; no gradual quality degradation like analog static

Disadvantages to consider:

• Cliff effect — when the signal drops below a threshold, it doesn't gracefully degrade (like analog getting staticky); it just cuts out completely
• Latency — digital encoding/decoding adds processing delay
• Complexity — significantly more complex hardware and software required

Go deeper:

• NATEL — Oral-History video on Switzerland's mobile network (PTT-Archiv, Wikimedia) — the Swiss side of the 1G→2G story: how the analog NATEL networks gave way to digital GSM, told by the people who built them.