A common concern at the recent IoT Utility Summit 2017 conference was worries around general interoperability. Many attendees that we talked to expressed concerns that IoT platforms would be difficult to manage due to the lack of standards and large diversity in devices and implementations. The adoption of standards would enable uniform management platforms and avoid technology silos.
Simple Network Management Protocol
Standard management protocols have enabled Operational Support Systems to deliver new services and insights from many vendors on a unified platform. The prime protocol that enable this capability is Simple Network Management Protocol (SNMP). Its flexibility enabled capabilities never originally conceived by vendors. One example is network discovery which allowed management systems to build relationships of networks. SNMP standards across hardware vendors has allowed software vendors to deliver this capability. From our experience, the real reason why SNMP dominated management protocols lies in the following:
- Ubiquity. All network devices support SNMP and as does monitoring software. It provides a generic standard that all devices must support.
- Documentation. Humans and machines can process the documentation in what’s called a Management Information Base (MIB).
- Extendability. Vendors can extend the schema for their products.
- Passive & Active. Active – events can be generated in real-time from the device to the management system. Passive, allows many management systems to collect metrics from the device as they need. These two methods of management provide flexibility to adapt to monitoring and networking constraints.
- Flexibility. TCP or UDP are supported depending on the resource concerns. I.e. UDP to be used for low bandwidth and loss can be tolerated. TCP if otherwise. Encryption is available if required.
IoT departs from traditional devices due to their resource constraints. This has lead to the adoption of alternative protocols such as as CoAP (Constrained Application Protocol) and MQTT (Message Queuing Telemetry Transport). CoAP is a “specialized web transfer protocol for use with constrained nodes and constrained (e.g., low-power, lossy) networks”. MQTT as defined by an OASIS standard is a lightweight, open and simple client server oriented publish/subscribe messaging transport protocol. These protocols provide advantages in speed, simplicity, low usage and low resource constraints. Yet, due to their very flexible nature they lack the ability to integrate to existing management stacks as they are intended to be used for data transfer not management. Additionally, an ongoing issue with these protocols is that they can easily lend themselves to proprietary lock-in as opposed to SNMP.
Something to consider, perhaps, is that the protocols for management and data transfer may not be the same. MQTT as an example is good for supporting the collection of data sets that are unlocked by the IoT devices but not necessarily for the management of the devices (unless you intend to use the data being collected as an indicator of device availability/health).
In Bridging the SNMP GAP: Simple Network Monitoring of the Internet of Things, Mihajlo Savić presents a solution to bridge the gap in monitoring with the introduction of these new IoT protocols by enabling SNMP access to monitoring data obtained from resource constrained devices that couldn’t or cannot support SNMP. They developed a Proof of concept SNMP server that would serve as a bridge between MQTT and CoAP protocols that could be leveraged by SNMP enabled systems.
Our experience at DeployPartners is that you never know what you might need from your devices in the future. As IoT devices become more complex a generic management protocol such as SNMP, should become a requirement if possible. For severely constrained devices such as sensors then an IoT to SNMP gateway should be considered to allow utilities to provide uniform management to manage to all their infrastructure.
If you want to talk IoT, SNMP, CoAP, establishing a de facto standard or just have a chat about leveraging your current management assets use the form below to get in touch and we’ll set up a meeting.