security

Defense Against SYN Flood

April 29, 2010

Increase size of connection table

Add more servers

Trace attack back to source

Ask your ISP to filter malicious packets

Add firewall

Typically “SYN proxy”

Partial solution was “SYN-cookies”

Reply to SYN with SYN-cookie

Allocate no resources until SYN-cookie is returned

Egress filtering restricts spoofed IP addresses