This document discusses Operation Support Systems (OSS) used by telecom providers to manage their networks. It mentions various network elements like the Base Station Controller (BSC), Radio Network Controller (RNC), and Home Subscriber Server (HSS). It describes the OSS software architecture using servers that support functions like Fault, Configuration, Accounting, Performance and Security (FCAPS). The document provides an overview of the hardware infrastructure including servers, storage, and backup systems that support the OSS. It is presented by an engineer from MTN Syria.