features needed in the substation network and environment including
segregation, prioritization, and rugged construction [ 4 ]. Most Ethernet
networks employ either specialized twisted pair copper wiring or optical
fiber, and standard designators identify the data rate and the medium
compatible with an Ethernet port. This data-rate indicator commonly
precedes the medium designation, indicating a rate of 10, 100, or 1,
megabits per second. For higher speed networks operating at 10 gigabits
per second, the IEEE uses the designation “10GBASE.” Many older cable
types were used in the past. At this time, 10/100BASE-T and 100BASE-FX
Ethernet networks are most likely to be employed in substation networks
[ 5 ].
Connecting SCADA wirelessly may carry on the vulnerability of
a wireless network. Communication between devices can be easily
intercepted and altered especially if it is not encrypted. Outsiders may gain
control of the wireless network and control the devices. Also wireless
networks are less stable compared to wired networks. But there are many
advantages from connecting SCADA on even though there are a lot of
issues surrounding it like:- Wide area connectivity and pervasive, Routable,
Parallel Polling, Redundancy and Hot Standby, Large addressing range,
Integration of IT to Automation and Monitoring Networks, and
Standardization [ 6 ].
1.2 Literature Review
There were many scientific researches that dealt with different
designs and applications to implement SCADA systems.
Raymond W., et al. in 2000 discussed the use of the WAP
(Wireless Application Protocol) architecture to provide a wireless channel
to access the database operating under the commonly used distributed
network protocol system running for SCADA in the power process plant.
They developed Distributed Network Protocol (DNP) to be applied in the