3Com OfficeConnect Remote 812 manual OfficeConnect Remote Filtering Capabilities

The OCR 812 provides an extensive set of data and call filtering capabilities. The OCR 812 supports the following filtering capabilities:

Input and output data filtering.

Source and destination address filtering. Protocol filtering.

Source and destination port filtering. A packet filter can control what services local or remote users can access.

Route filtering can filter source and destination addresses in packets that ￿exchange routing table information.

Established session filtering. A packet filter can permit users to connect with a remote network without letting remote users have access to the local network (or vice versa).

The OCR 812 provides an extensive set of data filtering capabilities. For instance, filters can accept packets only from specific addresses to provide added security, or filters can be added to reduce network traffic and improve overall performance.

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 the packet information using a 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 OCR 812 and is organized into the following sections:

OfficeConnect Remote 812 Filtering Capabilities Creating Filters

Assigning Filters

Applying Filters

￿Managing Filters

Filters can provide added security by accepting packets only from specific addresses or they can be added to reduce network traffic and improve overall performance. Filters can also be used to approximate spoofing when routers with different or incompatible spoofing methods are linked over the WAN. Spoofing is the use of a forged IP source address to circumvent a firewall.

This capability is useful for system administrators or users who wish to restrict access to the OCR 812.

set command idle_timeout <timeout> where <timeout> specifies the idle timeout period in minutes. By default, there is no idle timeout period.

￿Care should be taken to remember the configured password. If the password is forgotten, the unit must be sent back to 3Com support to have the feature disabled.

To set the idle timeout period, use the command:

6-46CHAPTER 6: MANUAL SETUP

OfficeConnect Remote

812Filtering Capabilities

Data Filtering Overview