3Com HomeConnect 3CP3647 Cli User's Manual

Also see for HomeConnect 3CP3647: Installation guide

Contents

4 FILTERING CAPABILITIESIntroduction The 3Com HomeConnect ADSL Modem Ethernet provides an extensive set of datafiltering capabilities. For instance, filters can accept packets only from specificaddresses to provide added security, or filters can be added to reduce networktraffic and improve overall performance.Packet filters control inter-network data transmission by accepting or rejecting thepassage of specific packets through network interfaces based on packet headerinformation. When data packets are received by a network interface such as anEthernet (LAN) or WAN port, a packet filter analyzes the packet information usinga set of rules you define. A filter then lets the packet pass through or discards it.This chapter contains information on the filtering capabilities for your 3ComHomeConnect ADSL Modem Ethernet. It is divided into the following sections:n Filtering Overviewn 3Com HomeConnect ADSL Modem Ethernet Filtering Capabilitiesn Creating Filtersn Assigning Filtersn Applying Filtersn Managing FiltersFiltering Capabilitiesof the 3ComHomeConnect ADSLModem EthernetThe 3Com HomeConnect ADSL Modem Ethernet supports the following filteringcapabilities:n Input and output data filtering.n Source and destination address filtering.n Source and destination port filtering.n Established session filtering. A packet filter can permit users to connect with aremote network without letting remote users have access to the local network(or vice versa).Filter Classes The 3Com HomeConnect ADSL Modem Ethernet supports the following filterclasses:n Input data - filter packets as they enter.n Output data - filter packets as they exit.Filter Types Filters can be classified by the following types: