3Com OfficeConnect Remote 812 manual Ipx, Ip-Rip

OfficeConnect Remote 812 Filtering Capabilities 6-47

Packet filters control inter-network data transmission by accepting or rejecting the passage of specific packets through network interfaces based on packet header information. When data packets are received by a network interface such as an Ethernet LAN or WAN port, a packet filter analyzes packet header information against a set of rules you define. A filter then lets the packet pass through or discards it.

Filter Classes The OCR 812 supports three filter classes:

Input data - filter packets as they enter.

Output data - filter packets as they exit.

￿Embedded bypass for periodic router protocol packets (IP RIP, IPX RIP and IPX SAP)

Each filter class can be identified further by the following types:

Filter Types Filters can be classified by the following types:

Data filters - based on protocol-specific packet information.

Advertisement filters - based on broadcast packet information (IP RIP, IPX RIP,

￿and IPX SAP).

Generic filters - based on packet structure.

Data Filters Data filters control network access based on the protocol, source / destination address, and port designation (e.g., TCP and UDP port designations) of the packet. The following table describes the data filters supported.

Table 6-3	Data Filters
Filter		Action
IP		Controls network access based on the protocol and source/destination address.
		IP filter rules allow filtering based on the source address, destination address,
		protocol type, source port, and port designation of the IP packet.
IPX		Controls network access based on the protocol and source/destination network.
		IPX filter rules allow filtering based on the source network, destination network,
		protocol type, source socket, destination socket, source node, and node
		designation of the IPX packet.
Bridge		Controls network access based on the source and destination MAC addresses.

Advertisement Filters Advertisement filters operate on network protocol packets that contain varying information such as SAP or RIP. Filtering of these packets is performed by the specific protocol process.

The following table describes the advertisement filters supported:.

Table 0-1Advertisement Filters

Filter	Action
IP-RIP	Controls the content of IP Routing Information Protocol (RIP) packets that are
	sent out or received on specific ports. The IP RIP filtering process filters addresses
	from the RIP packet upon transmission, and does not enter routes into the
	routing table upon receipt.