Instance IDs in SNMP -- why they are there and what they mean?
In SNMP, there are two types of objects: scalar and columnar.
"Scalar" objects are objects that are not in a table such as sysDescr, sysName, etc. They must have instance ID .0 in get/set requests and responses.
"Columnar" objects are objects that are defined in a table such as ifType, ifDescr, etc. They must have meaningful instance IDs (defined by index part of the table) in get/set requests and responses. A tool may add .0 for scalar objects but it wouldn't know what instance IDs to "add" for columnar objects when issuing GETs.
SilverCreek relies on the end user to add .0 or other more complicated instance IDs when issuing get/set request. As a protocol test tool, this approach is considered better to the general users of SilverCreek as they must understand what they are doing when testing SNMP using SilverCreek. As an example, if you want to send SNMP get/set requests in command line you must know this concept.