Invented by Sun; Yanjun, Batra; Anuj, Kneckt; Jarkko L., Epstein; Leonid, Myers; Steven A., Zhang; Yan, Liu; Yong

Wireless networks are everywhere today, connecting our phones, laptops, and other devices to the internet with ease. But while these connections make life easy, they also need to be secure and reliable. In this article, we will break down a new patent application focused on something called “protected trigger frames” in Wi-Fi networks. This technology is all about making wireless communications safer and more dependable. Let’s explore the background, the science behind it, and the key innovations it brings to the world of wireless networking.

Background and Market Context

Wireless networks, especially Wi-Fi, have become a basic part of our lives. We use them at home, at work, in coffee shops, and even at public parks. Wi-Fi allows many devices, like phones, tablets, computers, and smart home gadgets, to talk to each other and to the internet without any wires. The most popular Wi-Fi standards are made by a group called the IEEE, and they have names like 802.11ax, 802.11be, and soon, 802.11bn. These standards keep getting better every year, offering faster speeds, longer ranges, and support for more devices at once.

But as Wi-Fi becomes more important, it also becomes a bigger target for attackers. Hackers can try to trick or disrupt Wi-Fi networks in many ways. One way is by messing with “trigger frames.” A trigger frame is a special kind of message sent between devices (like between your laptop and your Wi-Fi router). It tells devices when and how to send their own messages, helping many devices share the airwaves without talking over each other. Trigger frames are especially important in new Wi-Fi standards that support lots of users at once, like in busy offices, stadiums, or apartment buildings.

In older Wi-Fi systems, trigger frames were not very well protected. That means a bad actor could send fake trigger frames, confuse devices, or even break the network. As Wi-Fi gets used in more sensitive places—like hospitals, banks, and factories—reliable and secure trigger frames are more important than ever. The market is demanding safer Wi-Fi, and the standards bodies are working hard to deliver it.

With new standards like IEEE 802.11bn on the horizon, adding protection to these trigger frames is now a hot topic. Companies that make Wi-Fi chips, routers, and other electronic devices are all racing to support these new features. The ability to offer “protected trigger frames” will soon be a must-have for anyone making serious wireless products. This is where the new patent application comes in, aiming to solve the exact problem of insecure trigger frames and make wireless networks safer for everyone.

Scientific Rationale and Prior Art

To understand why protected trigger frames matter, let’s first look at how Wi-Fi communication works. When many devices want to use the same Wi-Fi network, they need a fair way to share access. Otherwise, messages would collide, and everything would slow down. This is where trigger frames come in—they act like a traffic cop, telling devices when they can talk and what resources they can use. For example, in Wi-Fi 6 (802.11ax), trigger frames are used to organize “multi-user” transmissions, letting lots of devices send data at the same time in a well-ordered way.

But in traditional Wi-Fi, trigger frames were not always checked for authenticity or integrity. A hacker could send a fake trigger frame, causing devices to send data at the wrong time or with the wrong settings. This could lead to wasted bandwidth, lost connections, or even open the door to more serious attacks. In the past, most security work in Wi-Fi focused on protecting the bigger data packets, not these small control messages like trigger frames.

Some earlier attempts tried to fix this by adding simple checks, like a Frame Check Sequence (FCS), which is a basic way to spot errors. But FCS does not protect against someone purposely sending a fake frame—it just detects random errors. Later, some security protocols added things like Message Integrity Codes (MICs) and Packet Numbers (PNs) to bigger data frames, making sure they were authentic and hadn’t been tampered with. But this level of protection was rarely applied to control frames like trigger frames because of concerns about extra overhead and compatibility with old devices.

Another problem in the past was that security features sometimes made frames bigger and slower to process. Wi-Fi networks, especially in crowded places, need to be fast and efficient. Adding too much security can slow things down and make devices use more battery. So, finding the right balance between safety and speed has always been a challenge.

Recently, the IEEE working groups have recognized these problems. New draft standards, such as 802.11bn, are calling for ways to protect trigger frames better, but they also want to keep the frames small and efficient. Different research groups and companies have proposed their own methods, but none have become the final “gold standard” yet. Most prior art either focuses on data frame security or tries to bolt on simple checks that don’t really stop attackers.

This patent application steps in to fill that gap. It brings together the latest thinking about Wi-Fi security, multi-user management, and efficient frame design. It builds on the idea of using MICs and PNs for integrity, but adapts them to the special needs of trigger frames. It also finds clever ways to signal which frames are protected, which keys to use, and how to keep everything as small and fast as possible. In short, it stands on the shoulders of previous work, but solves new problems with fresh ideas tailored for today’s Wi-Fi networks.

Invention Description and Key Innovations

This invention centers on a new design for electronic devices, such as Wi-Fi routers and client devices, that can send and receive protected trigger frames. The goal is to make sure that when a device gets a trigger frame, it knows who sent it, that it hasn’t been changed, and that it can trust the instructions inside. Let’s break down how the invention achieves this in simple terms.

First, the device includes an antenna node and an interface circuit. The antenna connects it to the airwaves, and the interface circuit handles the details of communication. When it’s time to send a trigger frame, the device creates a special message that includes a clear sign that some or all of the frame is protected. This sign can be placed in commonly used parts of the frame, called the “common information field” or the “special user information field.” This makes it easy for the receiving device to spot and understand that the message is protected.

The protection itself is done using two main ingredients: a Packet Number (PN) and a Message Integrity Code (MIC). The PN is a unique number for each message, making it hard for attackers to replay old messages or guess what’s coming next. The MIC is like a digital signature, proving that the message hasn’t been changed by anyone else. Together, they make sure the frame is both authentic and untampered.

The invention is smart about where it puts these fields. Depending on the type of trigger frame and what the receiving device supports, the PN and MIC can be placed before the padding at the end of the frame. This makes it easy for the receiver to start checking the MIC as soon as it arrives, saving time and making the network more efficient. If the frame is an “initial control frame” (ICF), like a Multi-User Request to Send (MU-RTS) or a Buffer Status Report Poll (BSRP), there are special rules for how to include the MIC and PN, and even a Frame Check Sequence (FCS) if needed.

Another key idea is the use of a “key identifier.” This is a small piece of information included in the frame that tells the receiver which security key to use. This is important because Wi-Fi networks often update their keys to stay safe. If a device detects repeated MIC errors, it can ask the network to update the key, and the invention supports ways to handle key changes smoothly. For example, the access point might temporarily send two MICs—one with the old key and one with the new key—until all devices are updated. This avoids breaking connections during a key switch.

Efficiency is a big theme in this invention. The inventors have found ways to keep the extra protection overhead as small as possible. For example, they use clever encoding tricks to fit the PN and MIC into existing parts of the frame, sometimes even using reserved bits or special subfields. By doing this, they keep the frames small, which helps the network stay fast and devices save battery life.

The invention also supports flexible negotiation. When a client device connects to a Wi-Fi access point, they can negotiate whether to use protected trigger frames and which options to support. This means the invention works well with both new and older devices, making it easy for manufacturers to roll out the technology in real products.

From a technical standpoint, the patent covers not just the method of sending and receiving protected trigger frames, but also the hardware and software needed to do it. The claims include the design of the interface circuit, the way memory and processors are used, and even how the system handles group-addressed frames (sent to many devices at once) and individual frames. These details make the invention robust and ready for real-world use, no matter what kind of Wi-Fi environment it faces.

What really sets this invention apart is how it brings together security, efficiency, and compatibility. It gives device makers a clear roadmap for adding protected trigger frames to their products, meeting the latest standards, and keeping users safe. By making it easy to spot protected frames, manage security keys, and keep overhead low, the invention solves a problem that has long been a weak spot in Wi-Fi networks.

Conclusion

Protected trigger frames are quickly becoming a must-have feature for wireless networks. As Wi-Fi moves into more parts of our lives and faces ever-more complex threats, the need for secure, reliable ways to manage device communication is clear. This patent application delivers a well-thought-out solution, blending robust protection with the efficiency and flexibility that modern networks require. It adopts proven security tools like MICs and PNs but applies them in new, clever ways to control frames, ensuring both safety and performance.

For device makers, network operators, and end users, this means better protection against attacks, fewer dropped connections, and a smoother wireless experience. As the next generation of Wi-Fi standards arrives, inventions like this will play a key role in keeping our digital world both connected and secure.

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