Filling the Gaps in your Remote Monitoring & Control Network
by Chris Frith
Singapore, November 9, 2012--Increasing globalization, regulatory compliance obligations and the drive for efficiency gains has led to an exponential growth in Remote Monitoring and Control (RMaC) of property, plant and equipment as companies seek to build sustainable competitive advantages. This article provides a glimpse into this evolving field and how customers can navigate their satellite technology choices.
Digital postcards from the edge
Remote monitoring for our purposes, can be considered as that which makes available digital information from unit or a system to another at a different or distant geographical location, thereby minimising efforts to achieve a desired result. There are three distinct entities in the RMaC chain: (i) the remote sites or equipment being monitored; (ii) the communication channel; and (iii) the centralised monitoring station which has larger computing capacity and human interfaces. In some cases the communication channel can be bi-directional, with commands being sent to the remote device to perform a control action (e.g. open/close a valve).
Transition to IP
The bulk of remote monitoring and control (RMaC) data communications is via landlines and more recently cellular data devices; with satellite used to fill the gap when these terrestrial services are either unavailable or too unreliable. For landline-based monitoring networks the biggest challenge looming is transitioning to IP as telcos increasingly phase out more traditional copper-pair based products that they have relied on for many years.
In fact it is the age of some of these networks that in itself a problem. Many use serial based protocols that were designed to interact with mainframe computers. Such protocols are very “chatty” with lots of interaction between sender and receiver. Transitioning to IP can significantly increase data overheads and cause issues due to response time variability leading to time-outs. There is also a danger of increased data charges due to your TCP session being terminated prematurely; which can be compounded by them rounding up your session up to the nearest kilobyte or more. Finally, as with all IP communications, there is the need to consider security to prevent unauthorised access or hacking, particularly of critical infrastructure.
For this reason a number of equipment vendors such as Ultra AEP Networks offer devices that manage the interface between the legacy monitoring equipment and the data carriage, saving customers the expense of a large scale equipment refresh. AEP’s VadEDGE keeps the legacy devices happy whilst managing multiple communication bearers including satellite. Having management of the communications path enables data overheads to be trimmed, reducing costs. For critical infrastructure such units can also provide traffic encryption plus prioritise bearers on a least-cost basis, switching in the event the primary channel becomes unavailable.
Filling the gap
Satellite carriage for RMaC applications is typically based on mobile satellite (L-band) systems such as Inmarsat, Iridium and Thuraya. However, much like in the maritime market, VSATs are increasingly eating into the operators market share as customers wrestle with the trade-off between high usage costs on L-band systems versus the higher upfront costs associated with VSAT based systems. For non-critical applications, VSAT systems also offer the potential of supplementary uses, with quality of service controls used to ensure monitoring and control messaging receives priority.
While many customers may complain about the costs of L-band usage, they often have limited options for change due to other factors such as the amount of space available, need for mobility and coverage requirements. Despite this, competition amongst operators has led to some offering flat rate billing to selected customers in a bid to increase market share.
Customer choices
In general if you have an established monitoring network then IP interface devices can help you put off the costs of wholesale network replacement whilst enabling you to take advantage of the benefits of an IP-enabled environment. The challenge will then become the cost of your data carriage across the satellite. L-Band offers the potential of smaller unit size and near global coverage however its usage-based charge model will mean that accessing all this additional information might become prohibitively expensive. For those operating on more of a regional basis with adequate space for the larger antennas involved, VSAT based systems should be considered. VSAT systems with their typically larger data allocations and increased speeds can also offer the potential of supplementary uses.
How to choose?
The best way is start with your business objectives, the geographical areas in which you operate and the amount of physical space available to house the devices. This will quickly flush out what satellite options are available to you. Then find a service provider that is experienced in your industry. This will offer you the best chance of success.
----------------------------
Chris Frith is the founder and CEO of SatCHOICE, a new, global online marketplace that matches satellite communications suppliers with purchase-ready buyers. He can be reached at chris.frith@satchoice.com.