255-700-025
3-21
PacketStar
™
Access Concentrator 60 User Guide
, Issue 1
Release 6.3.0
Chapter 3 System Features
AC 60 Software Features
The Ethernet LAN bridging feature incorporates the following functions:
•
Bridging
Ethernet MAC layer data is encapsulated by using standards in the ATM
Forum document RFC 1483.
•
Filtering
Certain Ethernet frames are filtered out and not relayed, according to a
filtering database. This frame filtering prevents frames from being
transmitted unnecessarily across the ATM network. The Spanning Tree
Algorithm and Protocol is the mechanism used to populate the filter
database dynamically.
•
Bridge management
This function enables end users to manage configuration and
performance, and collect cell records and billing information. Standard
Ethernet MIBs, as defined in ATM Forum document RFC 1643, support
SNMP management.
•
Performance
The Ethernet module provides simultaneous operation on all ports.
Firmware Release Control
Note:
The Firmware Version Control window as described in the
procedure in the "Upgrading and Backing Up System Software
and Firmware" chapter should be used only on the advice of
Lucent Technologies NetworkCare (see the "Technical Support"
section in Chapter 1, "Getting Started.").
The PSAX 1250 Stratum module now has downloadable firmware, just as the
I/O and Server modules have had. Also, by enabling the Building Integrated
Timing Source (BITS) interface, the Stratum module can now accept inputs
Figure 3-5. Ethernet Bridging over an ATM Network (RFC 1483, AAL-5)
LLC
Layer
End Station
LAN
Bridge
MAC
Layer
LLC
Layer
End Station
LAN
MAC
Layer
AAL5
RFC 14583
MAC
Layer
AAL5
RFC 14583
MAC
Layer
ATM