Modbus
Cellular
Gateway
Index
skipping
is
used
to
reserve
slots
for
new
function
insertion,
when
required.
68
NAT,
Data
Encapsulation,
VPI
Number,
VCI
Number,
Schedule
Type,
Network
Monitoring,
IGMP
and
WAN
IP
Alias.
RFC
1483
Bridged
WAN
type:
Settings
include
Data
Encapsulation,
VPI
Number,
VCI
Number,
Schedule
Type,
Network
Monitoring,
IGMP
and
WAN
IP
Alias.
There
are
some
common
and
important
configuration
parameters
common
to
all
WAN
Type
as
listed
below.
Network
Monitoring
The
gateway
supports
failover
function
and
the
function
must
depend
on
the
correct
decision
when
a
connection
is
down.
Some
parameters
are
used
in
the
decision
process.
DNS
Query
/
ICMP
Checking
:
either
one
is
used
to
check
alive
for
a
WAN
connection.
Loading
Checking:
The
response
time
of
replied
keep
‐
alive
packets
may
increase
when
WAN
bandwidth
is
fully
occupied.
To
avoid
keep
‐
alive
feature
work
abnormally,
enable
this
option
will
stop
sending
keep
‐
alive
packets
when
there
are
continuous
incoming
and
outgoing
data
packets
passing
through
WAN
connection.
Check
Interval:
Indicate
how
often
to
send
keep
‐
alive
packet.
Check
Timeout:
Set
allowance
of
time
period
to
receive
response
of
keep
‐
alive
packet.
If
this
gateway
doesn’t
receive
response
within
this
time
period,
this
gateway
will
acknowledge
this
keep
alive
is
failed.
Latency
Threshold:
Set
acceptance
of
response
time.
This
gateway
will
record
this
keep
‐
alive
check
is
failed
if
the
response
time
of
replied
packet
is
longer
than
this
setting.
Fail
Threshold:
Times
of
failed
checking.
This
WAN
connection
will
be
recognized
as
broken
if
the
times
of
continuous
failed
keep
‐
alive
checking
equals
to
this
value.
Target1/Target2:
Set
host
that
is
used
for
keep
alive
checking.
It
can
be
DNS1,
DNS2,
default
Gateway,
or
other
host
that
you
need
to
input
IP
address
manually.
The
decision
flow
chart
of
keep
‐
alive
checking
for
a
WAN
connection
is
shown
as
below.
