Denial of Service

Denial of Service

1. Failure

   • Example: noise on a line, line cut accidentally, node/ device failure

2. Denial of Service

   • Physical DoS Attack
     • Example: line cut deliberately, noise injected on a line
   • Electronic DoS attack-crashing node/ device via software manipulation
     • Saturating devices
       • Connection flooding
         • it has no capacity to handle useful packets
           • ICMP (echo request, echo reply, definition unreachable, source quench)
             • Ex of attack using ICMP: echo-chargen attactk, ping of dealth attack
       • Syn flood
         • Based on properties of a session in TCP protocol suite
       • Redirecting traffic
         • Packet dropping attack
           • Ex: by advertising a false be path , by DoS attack