The system of Classes of Service (COS) helps defining rights for one or another extension in the PBX or Centrex systems. For example, few groups require more space for storing voice messages, while other need the redirection of calls to cell phones, the third does not have to make calls outside of the office network. With the help of this system one can change and configure settings.
Persia Telecom Co. is a subsidiary of IOEC (Iranian Offshore Engineering & Construction Company) in Islamic Republic of Iran that was established in 2004.
IOEC is the 1st Iranian general contractor in the Oil & Gas industry.