SCADA equipment manufacturers are following the move to Ethernet-based wireless communications. While IP communications offer better system management, the addressing required for these communications can tie up a network slowing the reception of the intended message. This paper offers a solution to the problem of large overhead messages in SCADA IPbased networks.
New monitoring and control equipment manufacturers are making it necessary to move from the familiar world of RS-232 serial to Internet Protocol (IP) based communications. The switch from serial to IP communications often intimidates system operators who are hesitant to rely on networks that share an organization’s LAN, require an understanding of new network design or are subject to the interference inherent in some spread-spectrum equipment.
GOALS AND OBJECTIVES
End-users are familiar with the benefits of licensed RF narrowband products that achieve greater distance than license-free equipment. SCADA systems operating on narrowband ultra high frequencies (UHF) often cover a 50 or even 75-mile (diameter) territory without repeaters while some very high frequency (VHF) systems reach in excess of 90 miles. Licensed systems routinely reduce the interference seen in wide-band unlicensed equipment. Licensing provides the added benefit of a governing agency and coordination by local frequency coordinators.
SCADA system integrators and operators are navigating the move to IP-based communications cautiously while they learn TCP/IP terminology and gain a working knowledge of Ethernet networking equipment. The goal of IP-based networks over narrowband frequencies is to create a system with manageable IP communications with the benefits of a narrowband system. Endusers desire Ethernet infrastructure with optimum data compression without reduced equipment features that may hinder network operation and monitoring.