When it comes to Network Discovery we are absolute market leaders..

When it comes to Network Discovery we are absolute market leaders and can determine router model by the sound of its Fan. Just kidding..

But here is how we actually do it.

Let say IP address 10.20.45.1 is alive and we need to determine what type of device this is.

Step 1: Perform SNMP Get operation for sysObjectID.0 (1.3.6.1.2.1.1.2.0)

snmpwalk -v2c -c public 10.20.45.1 sysObjectID.0

This OID stores platform specific string which suppose to be unique for each device type.

For example device responds with: .1.3.6.1.4.1.9.1.924

This string is called Platform Specific OID and contain Vendor code in seventh position.

Each vendor has IANA assigned unique number listed here https://www.iana.org/assignments/enterprise-numbers/enterprise-numbers

In our case code is “9” which means that this is a Cisco device.

The remaining numbers define platform info and that information is collected from MIB files published by each vendor which we all collected and combined into a single repository of 1200 vendors which contains now around 56,000 different platform OID which we all classified by Device Category and Model.

At the end we have very nice device classification tree like this