Actiontec MI424WR User Guide - Page 78

Chapter 6 Configuring the Router's Security 2. Check the "Block IP Fragments" box to protect the local network from a common type of hacker attack that uses fragmented data packets to sabotage the network. Note that VPN over IPSec and some UDP-based services make legitimate use of IP fragments. IP fragments must be allowed to pass into the local network to use these services. 3. Click OK to save changes. Access Control Access control is used to block specific computers within the local network (or even the whole network) from accessing certain services on the Internet. For example, one computer can be prohibited from surfing the Internet, another computer from transferring files using FTP, and the whole network from receiving incoming E-mail. Access control defines restrictions on the types of requests that can pass from the local network out to the Internet, and thus may block traffic flowing in both directions. In the E-mail example given above, computers in the local network can be prevented from receiving E-mail by blocking their outgoing requests to POP3 servers on the Internet. Access control also incorporates a list of preset services in the form of applications and common port settings. 75