The Industrial Internet of Things
Architectural principles of I2oT:
- ISA100.15 illustrates methods for segregating automation networks in zones and connecting the zones with conduits. The concepts for zones and conduits were developed by ISA99 for ISA/IEC 62443.
- ISA100.15 illustrates methods for creating and enforcing policies that determine which entities can communicate over industrial networks, and the allocation of bandwidth or relative priority of those communications.
- As a general principle, many automation nodes and networks have limited bandwidth and capability to serve data. The primary source of data from these nodes must be in separate buffers and caches with sufficient bandwidth for expected users. Direct access to nodes requires systematic limitation.
- Local autonomous control and local history collection and compression are two techniques that are used in industrial automation systems to deal with low bandwidth and/or high or variable latency in networks. Many proprietary schemes are used to fill these needs, and there is an opportunity to standardize these features.
Common network management—ISA100.20 is starting work on a recognized need for common network management. This is a gap that needs to be filled. Common network management is intended to provide a way of managing multiple diverse networks with common tools. Some of the tools already exist, but many networks are not designed to work with external tools. Some networks are unmanaged. This is an opportunity.
Common security management—This aspect will also need work. It is not easy to separate this need from common network management, and it may be handled by the same effort. This will need to include provisioning procedures and tools. Most industrial protocols do not include sufficient security. They need to be upgraded to include this as a standard feature.
Specifications and profiles to support compliance certification—We need plug and play, not plug and pray. This means that we will need enough compliance profiles and specifications that a certification body can do compliance testing. Standards developed by a standards development organization may support this cause, but will not be sufficient to meet industry needs.
What does the future hold?
There are multiple paths and even multiple end points for this technology migration. It is not certain what path(s) or endpoint(s) will be the final result. The only certainty is that this technology will change, and so far the changes have led to more diversity.
Current state—Many organizations are involved in pieces of the communication problem, but no single organization is involved in all aspects of this problem and no organization is well positioned to take the lead in coordinating this technology drift.
Some standards organizations have taken on the task of standardizing horizontal layers of the communication stack. IEE writes standards for the PHY/MAC (or link) layers. IETF writes standards for network and transport layers. Coordination at the boundary between the link and network layers (which is also an organizational boundary) is informal at best and sometimes appears to be a turf war.
Many foundations have taken a vertical approach to communication stack specifications and have written full top-to-bottom stacks. Many of these support only one PHY and one application and have a single stack in between. Others have multiple PHY layers available but with restricted stacks in between. These foundations are generally market competitors.
All of the organizations fill a need whether they are working on a horizontal or vertical slice of the communication problem, or just a little piece of the problem. All of these organizations could slowly converge on best-in-class technology, or not. If market forces do eventually drive this convergence, it is safe to assume that the convergence will happen very slowly and chaotically under market conditions.
Lead organization—Building a positive outcome will need a lead organization or a consortium of organizations to make this effort successful. It will involve liaison work with too many organizations to name, and will need executive sponsorship from multiple entities including vendors, standards organizations, and foundations.
Herman Storey is chief technology officer of Herman Storey Consulting, LLC.
See additional voices on the topic on the next two pages: