What is a Jamming Attack?
A jamming attack is a type of denial-of-service (DoS) attack in which a cyberattacker uses a device to intentionally create interfering radio signals that effectively “jam” the airwaves, resulting in the access point (AP) and any client devices being unable to transmit. Depending on the power of the radio transmitter and the location and influence of the jammer on the network, jamming can be a cause of significant disruption in wireless communication. There are four types of jammers1:
Proactive jammers. Proactive jammers are interfering whether or not there is data transmission between a transmitter and receiver. Proactive jammers are only working on one specific communication channel and will not switch until its energy has been exhausted. These jammers are easy to implement, but they are inefficient in both energy and effectiveness. The three types of proactive jammers are constant, deceptive, and random.
Reactive jammers. Reactive jammers only operate when they detect a network activity on a certain channel. Once the reactive jammer senses a transmission, it compromises the reception of the message. A reactive jammer can disrupt both small and large size packets. These jammers are more difficult to detect than proactive jammers because the packet delivery ratio (PDR) cannot be determined accurately in practice. Types of reactive jammers include reactive RTS/CTS and reactive data/ACK.
Function-specific jammers. Function-specific jammers are implemented by having pre-determined functions. These jammers can be proactive or reactive and can work on a single channel to conserve energy, or on can jam multiple channels and maximize jamming throughput regardless of energy use. Types of function-specific jammers include follow-on, channel-hopping, and pulsed-noise.
Smart-hybrid jammers. Smart-hybrid jammers are power efficient and effective. The main aim of smart-hybrid jammers is to magnify their jamming effect in the targeted network. They take care of themselves by conserving energy, as they place sufficient energy in the right place in order to hinder the communication bandwidth for the entire network or a large part of it.
Jamming is a very harmful DoS attack, so it is critical to prevent and detect it. The following tips can help you to protect your wireless network:
- Use an ethernet cable
- Reset your connection
- Know the signs of a jammed connection (all wireless connections in the area will be impacted)
- Use local storage
- Change your location
- Change your Wi-Fi frequency
- Change your Wi-Fi frequency channel
- Find and remove the jammer
- Call your service provider
1 Grover et al., 2014, “Jamming and Anti-jamming Techniques in Wireless Networks”