Security & Surveillance Systems Installation & Maintenance Includes installation and maintaining security & surveillance system facilities and public utilities to prevent burglary breaking in or sabotage or other hazardous acts, such systems involve alarum monitors, surveillance cameras and others   Internal Communication Network Installation & Maintenance Include designing internal communication systems and networks installed in large complexes, hotels, hospitals, public institutions, student hostels and others, also fixing telephone calls reception and answering machines and maintenance and repair services.