Greg Ferro made a great analogy in the above-mentioned podcast: NETCONF is like SNMPv2/v3 (the transport protocol) and Yang (the language used to describe valid NETCONF messages) is like ASN.1 (the syntax describing SNMP variables). However, there’s a third component in the SNMP framework: a large set of standardized MIBs that are implemented by almost all networking vendors.
It’s thus possible to write a network management application using a standard MIB that would work with equipment from all vendors that decided to implement that MIB. For example, should the Hadoop developers decide to use LLDP to auto-discover the topology of the Hadoop clusters, they could rely on LLDP MIB being available in switches from most data center networking vendors.
Apart from few basic aspects of session management, no such standardized data structure exists in the NETCONF world. For example, there’s no standardized command (specified in an RFC) that you could use to get the list of interfaces, shut down an interface, or configure an IP address on an interface. The drafts are being written by the NETMOD working group, but it will take a while before they make it to the RFC status and get implemented by major vendors.„