陜西星際電子科技發(fā)展有限責(zé)任公司共享解決方案paper

1、WHITE PAPERTackling the Challenges ofIndustrial Wireless for SmartOil FieldsJeffrey KeMoxa Product ManagerWHITE PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil FieldsAbstractOil and gas fields seem like a perfect market for wireless networksand a potentially lucrative one. Yet opera

2、tors are reluctant to use wireless, because of concerns about reliability and security in an industry where downtime can cost millions and the product is literally explosive.However, recent advances in technology are finally providing reliable, secure wireless systemsthat systems integrators can off

3、er to the energy industry with confidence.IntroductionModern oil and natural gas wells typically operate unattended for extended periods. Downtimemeans lost profitswhich could be thousands or even tens of thousands of dollars per hour fora new wellso oil companies are willing to pay a premium for an

4、 industrial grade system thatcanize their wellhead uptime. With modern sensor technologies, centralized wellheadmonitoring alerts operators to device failures, so they can take immediate action to bypass,replace or repair faulty equipment before it affects production. There are several ways tocollec

5、t the monitoring databut wireless technologies offer the lowest cost and the fastestdeployment.System integrators would love to use wireless, but their energy industry customers haveserious doubts about it, particularly in the most critical areas of production. In this whitepaper,we will discuss the

6、 two most common objections you will hear when upgrading an oil or gasfield with industrial wireless technologies: (1) Wireless communication is unreliable, and (2)Wireless communication is insecure.Benefits of Wireless Communications in Oil FieldsThe industrial world is at the beginning of a revolu

7、tionary change; lets call it the age of theIndustrial Internet of Things (Industrial IoT). The Industrial IoT collects and analyzes your oilfields performance data to bring cost reductions and greater efficiency. To achieve this, itrequires sophisticated modern communication technologies. With recen

8、t advances in robustwireless technology, you can now easily create a reliable and secure network to realize theIndustrial IoT concept. Here we will compare this new type of network with the traditionalwired solution to see what benefits wireless brings:1. Lower Implementation Cost and Faster Deploym

9、entavoiding the time and cost of layinghundreds or thousands of meters of traditional cables. With wireless, theres no need to digReleased on July 14, 2015© 2015 Moxa Inc.Moxa is a leading manufacturer of industrial networking, computing, and automation solutions. With over 25 years ofindustry

10、experience, Moxa has connected more than 30 million devices worldwide and has a distribution and servicenetwork that reaches customers in more than 70 countries. Moxa delivers lasting business value by empoweringindustry with reliable networks and sincere service for automation systems. Information

11、about Moxas solutions isavailable at. You may also contact Moxa byat info.How to contact MoxaTel: Fax:1-1-1© 2015 Moxa Inc.WHITE PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil Fieldstrenches or to run conduits through crowded, busy and hazardous environments.2. Reduced Mainten

12、ance Time and Costwith wired communication, paying for cable maintenance and repair staff is inevitable. Cables are vulnerable to accidental cutting,snap, or disconnection. Wireless communication narrows down the maintenance scopefrom lines to points. This can significantly reduce the maintenance ti

13、me and cost.izing System Uptimewith a redundant wireless design, multiple communication3.paths can ensure the highest system uptime, no matter whether there is a hardware failureor wireless interference.To realize all the above advantages, it is important to clearly understand the options you havefo

14、r creating reliable and secure wireless communications. We hope this white paper will helpintroduce the key concepts, and some potential solutions.As we discussed above, oil and gas industry customers have two common objections toaccepting wireless: reliability and security. We will discuss these ob

15、jections, and suggest howthey can be overcome.Challenge 1: Wireless Communication is UnreliableWireless choices: Defining the scopeThere are many wireless data technologies, for example: Bluetooth, Zigbee, WiFi (802.11-based systems), and mobile/cellular data, as well as proprietary microwave system

16、s. Forlonger-distance communication, WiFi and cellular technologies are now the most popularoptions, as they provide a relatively wider range and higher bandwidth.In the case of cellular data, the most common cause of communication instability is the serviceproviders cell tower becooverloaded by oth

17、er users, or suffering hardware failure.Technologies like Moxa GuaranLink or Cellular Connection Alive Check are generally used tomonitor cellular connection status and ensure the link stays upso we will not discuss cellulardata technology inin this white paper, and instead focus on WiFi.Unlike cell

18、ular, WiFi uses unlicensed public radio frequencies and therefore it is less strictlyregulated. This has helped WiFi technology grow rapidly in the past 20 years, in both usageand capabilities. For example, the data rate has increased 100x from 11 Mbps (802.11b) to1,300 Mbps (802.11ac). However, the

19、 openness of the WiFi market has resulted in atechnology that cannot always be relied upon. How can we enjoy the benefits of WiFis highbandwidth, without falling victim to its unreliability?Why do people think wireless (802.11) communication is unreliable?Before we talk about the solution, lets talk

20、 about why wireless is unreliable. Wireless signalsare transmitted through the air, and everybody must share the same small range offrequencies. Image this: if there are a hundred people in a room and all of them are talking atthe same time, they will probably all have to slow down and keep repeatin

21、g themselves inorder to be understood by thethey are talking to. WiFi devices are like a crowd ofpeople in a roomthe more there are, and the more they talk, the harder it becomes foranyone to be heard clearly. Simply speaking louder is not effective because everyone nearby2© 2015 Moxa Inc.WHITE

22、 PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil Fieldswill start to speak louder, too. (In fact, for wireless, speaking louder usually cannot be veryeffective because there are legal limits on transmitter power levels).Fortunately, there are many techniques that can improve communi

23、cations quality in these so- called multiple access (MA) situations. For example, using different frequencies (FDMA Frequency Division Multiple Access), or using different time slots (TDMATime DivisionMultiple Access).WiFi (based on the IEEE 802.11 standard) uses a dynamic version of TDMA: Carrier S

24、enseMultiple Access with Collision Avoidance, CSMA-CA. To explain this briefly: Every WiFi devicelistens briefly to the airwaves before transmitting, to detect if the frequency isto use(Carrier Sense). If no other device is transmitting nearby, then the device sends some data,otherwise it waits unti

25、l the frequency band is availablethe devices try to share the time. Thisis like waiting for a break in conversation before speaking. However, this method suffers fromseveral potential problems that make it unreliable. Here we discuss these problems:1.The frequency channel is overloaded. As we have m

26、entioned, CSMA-CA devices share thetransmission time with others by checking whether the frequency is available. So if thefrequency is fully and continuallyoccupied, the transceiver will just keepwaiting. When installing any newwireless devices, or moving existingequipment, it is standard practice t

27、ocheck which frequency channels areleast crowded, and use thosefrequencies. As wireless devicesproliferate, finding space becomes increasingly difficult.2.There is co-channel interference. Some people consider this part of the issue of overloadedchannels, but there is a differencebetween a legitimat

28、e signal andinterference. The definition of co-channelinterference is: Transmitting whileanother radio is transmitting. Suchinterference is usually caused bywireless radios that do not follow theCSMA-CA protocolintentionally orunintentionally. Intentional interferencecould even be a malicious attack

29、 inwhich someone is trying to hack or jamyour communications. An example ofunintentional interference is the “hidden-node” issue that is commonly seen inbadly set-up wireless networks andrequires enabling CTS/RTS. This caneasily cause co-channel interference thatmakes your wireless network unstable.

30、3.There is adjacent-channel interference. The public wireless frequency range is divided intoa small number of channels. Each is so narrow that some of a signals energy will “spill over”3© 2015 Moxa Inc.WHITE PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil Fieldsinto neighborin

31、g channels. Sometimes this prevents CSMA-CA from reliably detectingwhether a frequency is aly being used. As a result, even if we appear to have achannel available for our devices data, the signals transmitted only adjacentchannels can collide with each other and become unintelligible at the receivi

32、ng end. This problem is most commonly seen in 2.4 GHz channels (802.11b/g/n) as the available frequency range is narrower, compared to 5 GHz (802.11a).There is non-WiFi interference. Many other devices produce radio frequencies that interfere4.with WiFi communications. For example, consumermicrowave

33、 ovens emit energy around the 2.45 GHzfrequency, with far more power than a WiFi device.Some of this energy leaks out. So, if you are using an802.11b/g/n deviceto a microwave, your datatransmission can be severely disrupted.5.A moving obstacle blocks the line-of-sight. In an office, it is not necess

34、ary to have a line-of-sight to your access point, because, over short distances, radio signals can bypassobstacles by bouncing off walls and passing through some materials. However, for longdistance communication, line-of-sight is the best way to ensure wireless connection qualityand throughput. But

35、 if that line-of-sight is blocked by some large object, like a truck orcrane, you will usually experience a loss of connection or, at least, a drop in availablebandwidth.So how do we overcome all these interference problems?We dont, in the same way as we cannot always prevent a fiber cable from bein

36、g cut bysomeone excavating the road without checking the metro cable layout. And similarly, wecannot foresee if one of your subcontractors will use a proprietary communications solutionthat interferes with your WiFi or cellular links, or even if someone will deliberately attack yourwireless connecti

37、on.Of course, you should still use professional wireless installers to do a site survey when theyfirst install your wireless devices and ensure that everything is working well. But they cannotprotect you from the unexpected, such as an access point suffering a power failure, orsomebody nearby starti

38、ng to use the same frequency channel as you, or staff moving amicrowave ovento a wireless device.So, as we cannot overcome every possible problem in the real world, the only solution is tododge the interference. This is achieved with wireless redundancy. There are several differenttypes of redundanc

39、y that can be used:·Frequency-level redundancy with concurrent radio redundancy:The basic principle of frequency-level redundancy is to use two or more radio frequenciesto transmit the same data. So, if one frequency is blocked or jammed by radiointerferencesuch as another WiFi devices transmis

40、sionthe data can be sent over theother frequency instead. Using very widely-separated frequencies (such as the 2.4 GHz and5 GHz bands) prevents the same source of interference blocking both frequencies. Forexample, Moxas access points with Concurrent Dual-Radio Technology continually transmitthe sam

41、e data over two different frequencies simultaneously, so if one frequency is blocked,4© 2015 Moxa Inc.WHITE PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil Fieldsthey can instantly switch to the other stream of data, and the network will continueworking without interruption or

42、data loss.2.4 GHz5 GHz·Network level redundancy with AeroLink:Moxas AeroLinkcreates a reliable wireless bridge between two networks toprovide network-level redundancy. The technology guardsnumerous issues thatcould prove fatal for an unprotected wireless network:1.Communication Failover: AeroLi

43、nkdevices negotiate with each other toautomatically elect an active node for data communicationother nodes serve asbackups. Later, if the active node is no longer capable of sending data to its accesspoint, the other nodes will quickly re-negotiate to resume the communication viaanother path.2.Frequ

44、ency-Interference Failover: This concept works similarly to Frequency-levelredundancy, introduced above. If there is interference on the active communicationfrequency and data can no longer be transmitted, the network swiftly and automaticallyrestores the connection via a backup frequency.5© 20

45、15 Moxa Inc.WHITE PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil Fields3.Device Failover: A critical wireless network should never be disabled by a single-point-of-failure. AeroLinkcontinually monitors each devices status. If the activenode is disabled by a local power failure or h

46、ardware fault, the backup nodes willautomatically take over to keep the data moving.4.Scalable: AeroLinkis designed to allow almost unlimited backup paths,allowing users to create a completely redundant wireless network, safe from all theabove failures.5.Fast Recovery: Maintaining a redundant wirele

47、ss network is important, but its just asimportant to avoid seriously interrupting communications when a failure occurs.AeroLinkfailure.is designed to restore the communications within 300 ms from anyChallenge 2: Wireless Communication is InsecureHow is data at risk?Corporate users of WiFi and cellul

48、arthe most common wireless data technologieswereinitially concerned about the security risks of transmitting their information through the air.But those communication channels can now be encrypted for secure transmission. WPA2combined with AES provides strong encryption for WiFi. And in the case of

49、cellular, not only isthe data encrypted, but access to the frequency range is also restricted by law to strictly-licensed organizations and devicesunlike WiFi.6© 2015 Moxa Inc.WHITE PAPERTackling the Challenges of Industrial Wirelessfor Smart Oil FieldsHowever, despite this, data is still at ri

50、sk when it passes through the public Internet.For example, when you use cellular to collect data locally, you might assume your data is safely contained onsite. In fact, your data probably goes from the mobile service provider out onto the public Internet, before returning through your corporate rou

51、ter and firewall and finally to your monitoring center. How do you secure your data even though it passes through thepublic domain?Its now an increasingly common industry practice for data to be encrypted whenever it passesover the Internetfor example, companies such as Google encrypt all their user

52、s searches, and so on. All organizations can greatly improve their security with end-to-endencryption of data to keep data safe as it passes through the Internet or other less-securechannels.Why do users need cybersecurity?Forty-one percent of global organizations ait by one of the most common forms

53、 of cyber-attack, a Denial of Service (DoS or DDoS), at least once per year, with the energy industrytargeted more often than other sectors, according to a 2014 survey by global communicationscompany, BT. In a DoS event, an attacker floods the network with data to prevent it fromoperating normally.

54、If the attack is successful, communication can be stopped or severelyslowed, and poorly-designed communications hardware may crash. “A successful Denial ofService attack on the hazard management systems at an oil refinery would be catastrophic,”the BT report warned.Oil and gas companies are increasi

55、ngly aware of the mounting threats posed to their businessfrom online attacks. There are threats to their sensitive business information, and perhaps ofeven greater concern, to their operating control infrastructure. For example, network accessallows control of flow rates, pump speeds, valve opening

56、s, and numerous other physicalparameters that could cause extensive equipment damage or even harm to staff and the public,if they are tampered withor if access is simply denied to legitimate users by a Denial ofService attack. As Internet use has become more widespover the past decade, the oil andga

57、s industry has seen heightened risks surrounding the security of Internet-enabled equipment.A “defense-in-depth” approach should be applied to industrial control systems forofcritical equipment. Security coverage should extend to the entire automation network.Choosing the right industrial network security equipment could be the key to avoidingseriousand costlyissues in the future.So what can we do to make the netw