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Running H/F 1

2383BS–WLAN–01/04

Overview

The AT76C511 Dual Ethernet to Wireless LAN Bridge (DEW-B) is a single-chip solution

for interconnecting a Wireless LAN conforming to IEEE 802.11b standard with other

Wireless LANs (WLANs) and legacy LANs.

A DEW-B-based bridge acts as an Access Point (AP) for the 802.11 WLAN and coordi-

nates the traffic of the packets that are destined outside the WLAN using IP over

Ethernet. In case the WLAN user is mobile, roaming functions are also supported at the

DEW-B bridge. Its Dual Ethernet MAC architecture is useful in applications where bridg-

ing or routing is required between a public network through high speed links like an

XDSL modem and the customer premises network area where both WLAN and Ethernet

connections coexist. Figure 1 shows the topology described above which includes wire-

less and wired stations communicating through an Ethernet backbone and incorporating

the DEW-B, common Ethernet bridges and simple WLAN AP like the VNET-B

(AT76C510). It is also shows how this Customer Premises Network (CPN) can access

the Internet through a modem link (ADSL).

The data transactions over this unified CPN environment are categorized according to

the type of end-to-end devices.

End Stations Transactions

When two end stations communicate (irrespective to the type of network they belong)

the inter-networking between the different networks should be transparent.

Inter-networking Device

Transactions

The DEW-B device implements all necessary communication protocols for supporting

inter-networking functions, implements logical grouping of users independent of their

physical location and provides secure links by implementing encryption algorithms.