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©2020 Broadcast Electronics
SNMP
Simple Network Management Protocol is a member of the Internet Protocol standard communications
suite. The STX comes with a built-in SNMP agent (SNMP version 2c) for handling all request types included
in the protocol – GET, SET, GETNEXT, and GETBULK. The appropriate MIB for the version of SNMP agent
installed on the transmitter must be downloaded from the transmitter itself. As with any MIB, this ASCII
text file completely defines the data structure within the agent. The MIB also provides textual descriptions
for every accessible object.
SNMP IS FOR ADVANCED APPLICATION INTEGRATION. THIRD PARTY
APPLICATIONS THAT UTILIZE THE SNMP INTERFACE ARE NOT SUPPORTED BY BE.
To download the file access the web interface using a standard web browser. Right click on the link titled
“SNMP MIB File” and then “Save link as…”, a local copy of the MIB file wherever desired for use in an
SNMP manager application. Alternatively, click the link and navigate to the file in the browser. Right click
anywhere in the viewing space and click “Save as…” Simply remove the .txt extension (leaving only the
.mib extension) and save at the desired location.
An SNMP manager application must be utilized in order to access the interface. Integrating a manager
into custom station automation programs provides countless possibilities. Alternatively, various third
party MIB browser GUI applications are available for free download; however Broadcast Electronics does
not endorse any specific application. Simply direct the manager to the Ethernet port for communication
across a network.
Authentication
Data is accessible by using the correct community strings for the desired login level. The formula
for these strings is a combination of the login type – chief, user, or operator –, a delimitating ‘+’
character, and the 8 digit numerical password associated with that login type. For example,
“chief+12345678” in both the read community and write community passes authentication and
allows read and write to essentially every object in the MIB with the appropriate max-access
type. User and Operator login types provide more strict control over what settings can be
modified and commands issued in the system.
Objects
The SNMP interface utilizes tables wherever it makes sense to communicate data in an indexed
fashion. To accommodate a scalable transmitter product design, for example, almost all PA data
is structured as tables by using the PA number as the index. This works by appending “.#” to the
object where # is the PA number. Note that a normal “leaf” node is accessed by appending “.0”
as in …38118.2.2.2.0, the object for system forward power.
