Modbus
Cellular
Gateway
Index
skipping
is
used
to
reserve
slots
for
new
function
insertion,
when
required.
337
Configuration
Path
[Port
Configuration]
‐
[Configuration]
Operation
Mode
Modbus
Interface
RS
‐
485
Baud
Rate
(bps)
Same
as
the
one
of
connected
Modbus
devices
Data
Bits
Same
as
the
one
of
connected
Modbus
devices
Stop
Bits
Same
as
the
one
of
connected
Modbus
devices
Flow
Control
Same
as
the
one
of
connected
Modbus
devices
Parity
Same
as
the
one
of
connected
Modbus
devices
Configuration
Path
[Modbus]
‐
[Gateway
Configuration]
Gateway
■
Enable
Serial
Protocol
Same
as
the
one
of
connected
Modbus
devices
Serial
Response
Timeout
1000
Configuration
Path
[Modbus]
‐
[Modbus
TCP
Configuration]
Listen
Port
502
TCP
Connection
Idle
Time
300
sec
Maximum
TCP
Connections
4
Trusted
IP
Access
Specific
IP
Configuration
Path
[Modbus]
‐
[Trusted
IP
Definition]
ID
1
Source
IP
203.95.80.22
‐
203.95.80.29
Enable
■
Configuration
Path
[Modbus]
‐
[Modbus
Priority]
Priority
1
2
Settings
IP
Address
:
203.95.80.22
IP
Address
:
203.95.80.23
Enable
■
Enable
■
Enable
Scenario
Operation
Procedure
In
above
diagram,
the
"IoT
Gateway"
is
the
gateway
of
Network
‐
B
at
branch
office
and
the
subnet
of
its
Intranet
is
10.0.75.0/24.
It
has
the
IP
address
of
10.0.75.2
for
LAN
interface
and
118.18.81.33
for
WAN
‐
1
interface.
It
serves
as
the
Modbus
gateway.
Moreover,
there
are
some
Modbus
devices
are
attached
to
the
IoT
Gateway.
A
Modbus
TCP
Master
is
located
behind
the
"Remote
Gateway"
in
Network
‐
A
for
headquarters.
The
"Remote
Gateway"
is
the
gateway
of
Network
‐
A
and
the
subnet
of
its
Intranet
is
10.0.76.0/24.
It
has
the
IP
address
of
10.0.76.2
for
LAN
interface
and
203.95.80.22
for
WAN
‐
1
interface.
It
serves
as
a
NAT
gateway.
At
first,
the
Modbus
TCP
Master
creates
a
TCP
session
to
the
IoT
Gateway
for
delivering
Modbus
commands
and
responses.
During
normal
operating,
the
Modbus
TCP
Master
sends
requests
to
the
IoT
Gateway
for
