DENIAL OF SERVICE (DoS) ATTACK PREVENTION THROUGH RANDOM ACCESS CHANNEL RESOURCE REALLOCATION

摘要

A system (10) and method to substantially prevent Denial of Service, DoS, attacks due to Random Access Channel, RACH, overload in cellular wireless networks. Once a mobile handset (12) is identified to cause or contribute significantly to a RACH overload of the cell, the system sends (28) a special System Information Block, SIB, message targeted to that mobile handset and instructing it to redirect its RACH signaling to a separate RACH/PRACH, Physical Random Access Channel, resource or to a small part of the current RACH/PRACH resource. The use of a separate RACH/PRACH resource such as frequency, preamble sequence, and/or radio subframe access slot to "absorb" high volume RACH signaling traffic from a small number of malicious/defective mobile handsets substantially prevents signaling Do S attacks from overloading the regular RACH/PRACH resource in the wireless network (14) and makes it more robust to such attacks.