Table of Contents
This chapter explains why current solutions are bad for the mobile networks and how we designed this server to solve this issues.
In order to understand the complete problem, we need to introduce you on how the mobile nerworks work at radio level and also how the carriers have their network infrastructure. So, go ahead !
Since on IPv4 the amount of free adresses is really low, celular networks were divided into the ones with real IPv4 adresses (normally for 3G modems) and private adressing model for handsets.
On the case of private networks, it's obvious that it's not possible to directly notify the handset when the server has a notification for it, so smartphone manufacturers decided to maintain opened channels with their servers so it's possible to notify handsets asynchronously.
On the other hand, if the handset has a public address, or is using IPv6, it's teorically possible to send the message directly making third party solutions unuseful, however in order to protect users, carriers can deploy firewalls to avoid direct access from Internet to the handset.