For defense against external threats, the TL-ER604W features automatic protection to detect and block Denial of service (DoS) attacks such as TCP/UDP/ICMP Flooding, TCP Scanning, Ping of Death, and other related threats. For better management of the internal network, the TL-ER604W also allows administrators to set rules to block specific web sites and IM/P2P applications with just one click. The TL-ER604W can also restrict specific services such as FTP, HTTP, and SMTP.