3Com Router 3000 Ethernet FamilyConfiguration Guide Chapter 6 IP Accounting Configuration3Com Corporation6-1Chapter 6 IP Accounting Configuration6.1 Introduction to IP AccountingIP Accounting counts inbound and outbound IP packets on the router. These IP packetsinclude those sent and forwarded normally as well as those denied by the firewall.The statistics of the IP Accounting provide information about source and destination IPaddresses, protocol number, packet sum, and byte sum. The statistics are sorted intodifferent tables for display depending on whether IP packets pass the firewall andwhether they match IP accounting rules.Each IP accounting rule consists of an IP address and its mask. The rule list recordsnetwork segment addresses, which are the results of ANDing IP addresses with theirmasks. An IP packet is sorted as follows:z If the source or destination IP address of the IP packet matches a networksegment address in the rule list, the packet is recorded in an interior hash table asa valid packet (a packet not filtered out by the firewall) matching the rule.Otherwise, the packet is recorded in an exterior hash table as a valid packet notmatching the rule.z If the packet is filtered out by the firewall configured on the interface when itreaches a router, it is recorded in the firewall-denied hash table as an invalidpacket.6.2 IP Accounting ConfigurationTo configure IP accounting, first enable it, and then specify one or more types ofpackets to be counted on an interface. After that, the router can start counting IPpackets.6.2.1 Preparations for IP Accounting ConfigurationsYou have assigned an IP address and mask to the interface, on which packets are to becounted. In addition, a firewall is configured on the interface.6.2.2 IP Accounting Configuration TasksThe following sections describe IP accounting configuration tasks:Table 6-1 IP accounting configuration tasksOperation Command RemarksEnter system view system-view ––
