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"The first is the operating system kernel in the air link processor of mobile phones. In most current phones, that's an L4 kernel with a full proof of correctne

"The first is the operating system kernel in the air link processor of mobile phones. In most current phones, that's an L4 kernel with a full proof of correctness. Since any mobile phone can potentially knock out all phones for some distance around if it doesn't follow the sharing rules for the air link, this is important to carriers. They got it right. Nobody talks about this much, but if that layer had problems, there would be regular cellular blackouts." That's... an interesting claim. You're basically saying that a cellular network is wide open to DOS attacks. I would need to see some serious proof before accepting such a claim.

thibauts 12y ago
Any wireless link is open to DOS attacks: jamming.
- antimagic 12y ago
  Jamming is not a DoS attack. The essential feature of a DoS attack is that it forces the receiver to use resources, which it can then not attribute to legitimate users of the service. Jamming does not force a cell tower to use resources, hence it's not a DoS attack. To put it another way, if jamming is a DoS attack, then so is hacking a server and reconfiguring its DNS. But we don't call that type of attack a DoS attack, we call it a penetration, or simply a hack. And yes, wireless communications are susceptible to more physical attacks, such as jamming, but jamming is a) easy to track down, and hence dangerous to execute, b) expensive, you need to invest in special hardware to do it and c)surprisingly difficult to effectively execute in a radio environment like a cell network, which is generally quite adept at routing around things like jamming ( if you put your jammer between me and the antenna, my phone will in all likelihood simply find another antenna to connect to on the other side of me - with signal strength dropping as the square of the distance, your jammer is going to need to be BIG to jam me effectively).
Animats 12y ago
GSM-type cellular uses time division multiplexing, with many handsets on the radio channel. Any handset which transmits during another handset's time slot will interfere with the other handset's signal.

thibauts 12y ago

Any wireless link is open to DOS attacks: jamming.

antimagic 12y ago
Jamming is not a DoS attack. The essential feature of a DoS attack is that it forces the receiver to use resources, which it can then not attribute to legitimate users of the service. Jamming does not force a cell tower to use resources, hence it's not a DoS attack. To put it another way, if jamming is a DoS attack, then so is hacking a server and reconfiguring its DNS. But we don't call that type of attack a DoS attack, we call it a penetration, or simply a hack. And yes, wireless communications are susceptible to more physical attacks, such as jamming, but jamming is a) easy to track down, and hence dangerous to execute, b) expensive, you need to invest in special hardware to do it and c)surprisingly difficult to effectively execute in a radio environment like a cell network, which is generally quite adept at routing around things like jamming ( if you put your jammer between me and the antenna, my phone will in all likelihood simply find another antenna to connect to on the other side of me - with signal strength dropping as the square of the distance, your jammer is going to need to be BIG to jam me effectively).

Animats 12y ago

GSM-type cellular uses time division multiplexing, with many handsets on the radio channel. Any handset which transmits during another handset's time slot will interfere with the other handset's signal.