Masterclock
GMR
User
Manual
v2
–
2016.12
46
SNMP
–
Simple
Network
Management
Protocol
SNMP
SNMP
is
a
standard
way
to
monitor
a
device
on
an
Ethernet
network.
It
is
used
to
monitor
the
health
and
network
status
of
a
device
on
an
Ethernet
LAN.
SNMP's
purpose
is
only
to
convey
status,
not
for
controlling
the
device.
The
GMR
runs
firmware
called
the
SNMP
Agent.
The
user
runs
software
called
an
SNMP
Manager
(or
MIB
Browser)
on
a
PC.
THE
USER
MUST
ACQUIRE
THE
MANAGER
SOFTWARE;
Masterclock
does
not
offer
one.
Our
Agent
supports
versions
1
and
2
of
SNMP.
The
PC
on
which
the
Manager
is
running
must
also
have
SNMP
abilities
for
Manager
and
Agent
to
communicate.
Windows
7
and
XP
support
SNMP
v1
and
2.
The
user
runs
the
Manager
to
get
the
data,
issuing
requests
to
the
Agent.
If
some
security
tests
are
passed,
then
the
Agent
responds
with
the
data.
The
SNMP
Control
window
in
WinDiscovery
provides
START
and
STOP
buttons
for
the
user
to
turn
the
SNMP
Agent
on
and
off,
and
offers
a
few
options,
like
Name
,
Location
and
Contact
.
Thus
a
device
could
be
named
"GPS
Ref",
with
the
location
"Bldg
1
‐
A",
and
the
contact
"636
‐
724
‐
3666".
A
Custom
Community
name
can
be
created
(community
#2)
and
put
to
use
by
making
it
the
Current
Community
,
providing
some
security
if
the
name
is
kept
secret.
Trap
Receivers
are
the
IP
addresses
of
PCs
to
which
traps
are
sent.
Traps
are
messages
that
the
Agent
can
send
to
the
Manager
without
being
asked.
They
tell
of
events
like:
1.
Device
Restart
2.
Ethernet
Link
Up
3.
Authentication
Failure
(Community
mismatch)
In
addition
to
that
standard
SNMP
data,
Masterclock
has
created
a
custom
set,
called
a
custom
MIB,
which
can
be
imported
into
an
MIB
Browser
(Manager).
It
is
available
for
download
from
our
site.
To
the
left
is
a
display
from
a
MIB
Browser
of
the
type
of
data
this
MIB
enables
the
user
to
receive
from
the
GMR.
When
the
user
double
‐
clicks
on
an
entry
the
Agent
is
asked
for
the
data,
and
if
returned
it
is
displayed,
along
with
descriptive
text
from
the
imported
MIB.
