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How Deep Packet Inspection Is Changing Security in the IoT Age

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Deep packet inspection (DPI) looks at the contents of data packets, rather than just their headers, leading to more effective security for your network devices.

Increasing cybercrimes and web attacks prove that the existing web security is under threat in a continuous manner. Hackers are hungry to sneak into your web security and destroy that web application you worked so hard on. Moreover, with each passing day web attacks are getting smarter, and fighting them is a bottom-line requirement for your online business in order to stay afloat on the web. So, what does your web security standard desperately need? Continuous evolution backed by the research and analysis of recent web attacks.

Deep packet inspection (DPI) is one of the strongest players in the web security niche and it has the potential to outsmart modern web attacks. DPI is an integration of security functions, user service and network management, and these parameters are the building blocks of modern web security protocols. Furthermore, there is a high demand for a versatile web security layer in every sector of the web like big enterprises, global telecom services and governments. The internet of things (IoT) is becoming a necessary evil for the modern world, as it is fostering new ways to build web attacks, and DPI is one of the best weapons we have for combating these threats.

What Is Deep Packet Inspection?

Deep packet inspection, or information extraction (IX) is actually a process of network packet filtering. In this method, the data part of a packet is examined at an inspection point created for the detection of any unwanted activity, such as spam, viruses, intrusions, or to define a network’s criteria to maintain its flow to the proper destination. The system is also capable of extracting statistical data from the Open Systems Interconnection (OSI) model application layer. (To learn more about OSI, see An Introduction to the OSI Model.)

Among the whole collection of headers involved in IP packets, network equipment requires only the first one of them (called the IP header) for operating normal tasks. But the second header (like TCP or UDP) is generally used in shallow packet inspection or stateful packet inspection. The well-known and popular methods for acquiring data packets from deep packet inspections are port mirroring or SPAN ports and optical splitters.

Now, you may be asking how IoT comes into this, right?

There are two core needs for building an IoT network. One is the network connectivity and the other is data packets. IoT devices are governed by the never-ending stream of data packets which are spewed out by the web or local IoT master controller. So, data packets act as the blood for the body of IoT devices and networks.


Now, we can understand that if data packets have the governing authority to control a wide network of IoT devices, they also have the power to destroy the whole network. Even a single malicious data packet can instantly uproot any IoT network. Thus, we need a strong shield which can ensure the trustworthiness of every single data packet. We need DPI to protect IoT networks and devices, and we need it now. As a result of its effectiveness, enterprise-level institutions are using DPI in a range of their applications. Telecommunication and government organizations are harnessing the power of this modern technology by implementing it in various sectors.

Why Is It Important?

As we all know, a computer’s input and output of information takes the form of data packets, where the header defines the characteristics, purpose and destination of the packets. Then the information flows through the global network to reach the destination. This method is more effective and dependable in the field of error checking in a single flow, compared to the individual character checking method. That’s why NASA also configures their deep space data transmission to work in a similar way.

Now, this is the place where DPI plays an important role. In the entire network of worldwide data flow, almost all of the information passes through unmonitored. In this case, DPI implementation involves uncovering the identity of the packet information. It doesn’t simply check a packet’s header and footer, but scans the data content in each packet. Only after meeting some special criteria of a highly selective firewall, the packet gets re-routed to a particular path which best suits it, depending on the bandwidth measurement.

Undeniably, DPI is the most efficient way of straining out every possible malady over the entire data network by disassembling and examining the payload, reassembling it, and then determining whether to reject it or to transmit it in the most suitable traffic. Not only that, DPI engines strengthen the security protocol by implementing stealth payload detection, signature matching and other similar activities.

Recent Web Attacks and Their Nature

Cyberattacks have been plaguing the web in numerous ways for a long time. Sometimes it’s individual attacks over personal or enterprise web systems, and sometimes it acts more heinously over an entire nation. As much as our planet is depending on the online data system to connect the entire Earth, cybercrime is growing in a similar manner with each passing day.

From embedding spyware on a PC to demolishing the entire infrastructure of a nation – or even the world – the range of cybercrimes are altering the fate of the humankind in many ways. Activities like the Stuxnet worm have proved the constant growth of the more sophisticated and destructive nature of malicious entities. Cyberwarfare advances on attacking and defending data inhabiting cyberspace use prolonged campaigns or series of them, as well as destroying the ability of their opponents to do the same, and install technological weapons to attack the computer systems of others. (For more on cyberwarfare, see The Cyber War Against Terrorism.)

Cyberterrorism is defined as “the use of computer network tools to shut down critical national infrastructures (such as energy, transportation, government operations) or to coerce or intimidate a government or civilian population.” However, the newest addition to the cybercrime list is striking at the security of the internet of things. The nature of these attacks doesn’t differ from the conventional style, but is at a larger scale, where the simple hacking activities can put millions of connected devices at risk.

Simply put, the hackers have not really changed the nature of their actions, but they are advancing the scale of activities depending on the setups, environment and other factors.

How DPI Guards Your Web Application/Website

At the time of data transmission between the client and the server, the packet inspection operates through equipment implemented between the paths connecting the server with the client. According to Christopher Parsons of the University of Toronto, three types of packet inspection are categorized based on their depth of investigation, in which DPI occurs at the last layer.

Firewalls use shallow packet inspection, which searches only through the header by focusing on the source and destination of the data packet. Medium packet inspection examines not only the header, but also a small portion of the payload with the help of some equipment placed between the computer and the internet gateways.

Lastly, DPI digs through the origin as well as the data content up to the destination. This technology searches for protocol non-compliance, any virus, spam, or malicious coding or any special kind of data requiring monitoring. The importance of DPI technology lies in its range of uses, varying from analysis and interception of the data packet to storing and interpreting the contents of the packets.

The Advantage of Employing DPI

DPI accomplishes different purposes for the advancement of internet services. The following are some of them:

  • QoS and Network Management: In case of network management and quality of service (QoS), DPI has proved its powerful impact by allowing ISPs to block or limit specific applications, and consequently improving the performance in streaming, telephony and gaming. The consistent service quality comes with low jitter, low delay, and high reliability within a system for maintaining acute sensitivity. Since DPI looks through the content of the packet, it also performs classification of the information based on a formulated policy, and hence clears out the pathways of specific traffic.
  • Security: DPI was designed with the single vision of securing networks and protecting them against transmitting viruses or malicious software. Added to this, shallow packet inspection is used to prevent any unwanted users from joining a wireless network.
  • Surveillance: Surveillance is the most important part of security. It’s a forecast model for any security system. Now, DPI enables network managers to look deeply into every data packet, and this is the most powerful weapon one can ask for. Moreover, in certain countries, in order to do business, ISPs need to have some surveillance attributes integrated within their system.

It’s true that DPI is more than just a security standard if it’s employed with a dedicated purpose.

What’s the Future of DPI?

The future of data protection is under a real threat. With each passing minute, hackers around the globe are getting smarter and designing new web threats. We have to understand that only 15 years ago, IoT was a mere buzzword to us, and at that time there were limited ways to get connected to the web for us. We used to access the web from our personal computers, laptops and our smart handhelds. But, today is different. Now, we are surrounded by devices which are always connected to the web and are also governed by it. Undeniably, the World Wide Web has penetrated much deeper into our daily lives through IoT-powered devices, and increasing cyberattacks are a matter of serious concern for us.

New technology like deep packet inspection is the lifeline for us, as it has all the potential to look deeply into every data packet which is transmitted from other sources and enters our system. Security without a stringent inspection is a failed idea and DPI is here to make its mark.


Data security is the demand of the day, and deep packet inspection can ensure this. DPI is a reason for celebration for web users. DPI is a shield for us, as it adds an enhanced level of data security to our existing web security system. The cyber world has experienced the blow of heinous attacks like DDoS, ransomware and others. Further, in this big data arena, we do believe that data is the most valuable cyber commodity – and there’s no denying that belief is justified.


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Kaushik Pal
Technology writer
Kaushik Pal
Technology writer

Kaushik is a technical architect and software consultant with over 23 years of experience in software analysis, development, architecture, design, testing and training. He has an interest in new technologies and areas of innovation. He focuses on web architecture, web technologies, Java/J2EE, open source software, WebRTC, big data and semantic technologies. He has demonstrated expertise in requirements analysis, architectural design and implementation, technical use cases and software development. His experience has covered various industries such as insurance, banking, airlines, shipping, document management and product development, etc. He has worked on a wide range of technologies ranging from large scale (IBM…