Intel IXP400 Access-Layer Components Ethernet Database IxEthDB API, IxEthDB Functional Behavior

Intel® IXP400 Software

Access-Layer Components:	10
Ethernet Database (IxEthDB) API

This chapter describes the Intel® IXP400 Software v2.0 “Ethernet Database API” access-layer component.

10.1Overview

To minimize the unnecessary forwarding of frames, an IEEE 802.1d-compliant bridge maintains a filtering database. IxEthDB provides MAC address-learning and filtering database functionality for the Ethernet NPE interfaces. IxEthDB also provides the configuration and management of many of the Ethernet subsystem NPE-based capabilities, such as VLAN/QoS, MAC address firewall, frame header conversion, etc.

10.2What’s New

The following changes and enhancements were made to this component in software release 2.0:

•The Ethernet subsystem has been enhanced to include support for the Intel® IXP46X Product Line of Network Processors. This includes supporting the MII interface attached to NPE-A. All enumerations and definitions reference the Ethernet port on NPE-A as Port 2, except for the ixp_ne_dest_port and ixp_ne_src_port IX_OSAL_MBUF fields.

Note: The Intel® IXP46X product line processors include an option for a 4-port SMII capability, using 4 Ethernet coprocessors on NPE-B. In software release 2.0, this functionality is not supported. Only a single MII interface on NPE-B is supported.

10.3IxEthDB Functional Behavior

There are two major elements involved in the IxEthDB subsystem: a software database that executes on the Intel XScale core of the processor, and one or more Network Processing Engines (NPEs) that are capable of making decisions or performing manipulations on the Ethernet traffic that they encounter. While the capabilities of the NPEs are determined by the microcode that runs on them, the specifics related to how the NPE should drop, forward or manipulate the Ethernet traffic are managed by the IxEthDB component.

IxEthDB handles the configuration of several Ethernet subsystem features:

•MAC Address Learning and Filtering

•Frame Size Filtering

•Source MAC Address Firewall

•802.1Q VLAN

Programmer’s Guide	IXP400 Software Version 2.0	April 2005
	Document Number: 252539, Revision: 007	155