User's Manual

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3.2.2. DOS
Before taking about the DDOS service, it will introduce DDOS Attack first. DDOS attack stands
for denial-of-service attack (DoS attack) or distributed denial-of-service attack. It is an attempt
to make a computer resource unavailable to its intended users. One common method of attack
involves saturating the targeted machine with extern al communications requests, such that it
cannot re spond to legitim ate traf fic, or res ponds so slo wly as to be ren dered ef fectively
unavailable. DDOS se rvice here is used to prevent DDOS At tack, and it provides T CP SYN
Flood, UDP Flood, ICMP Flood, and Port Scan for selection. The definition for each field is
shown on Table 11.
Figure 23 Advanced>Firewall>DDOS
Name Description
TCP SYN Flood It will prevent SYN flood from WAN or LAN
UDP Flood It will prevent UDP flood to WiMAX outdoor CPE
ICMP Flood It will prevent ICMP flood from WAN or LAN
Port Scan
It will prevent port scanning from WAN and issue an alarm entry in
the system log.
Save Commit the changes made and save to WiMAX outdoor CPE
Cancel Reset fields to the last saved values.
Table 11 Field definition for Advanced> Firewall>DDOS