By using Portech SBK-32 expander for 32 SIM-cards, you can increase the number of channels in the Portech MV-37X GSM VoIP gateway series using the Internet.
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.