Default Atm Module Configurations; Bridging And Routing Over Atm Ports - Extreme Networks BlackDiamond 6800 Installation And User Manual

Note: The ATM module can support one PVC per port for each VLAN. The
BlackDiamond 6800 series switch can support 3000 VLANs.

Default ATM Module Configurations

When the BlackDiamond 6800 series switch is powered on, the ExtremeWare software
determines which slots are occupied by I/O modules, determines whether it has a
configuration for each module, and generates a default configuration for each slot that
is occupied by an I/O module that has not yet been configured. The default
configuration is the minimal set of configuration parameter settings that will allow the
I/O module and its ports to function.
By default, only ports 1 and 3 on the ATM module are assigned to the default VLAN,
while ports 2 and 4 are not assigned to a VLAN. By default, ATM scrambling is enabled
for all ATM ports. Before any data can be forwarded across an ATM port, PVCs must be
configured on the port and mapped to a VLAN. Use the
command to configure PVCs on the port and map PVCs to a VLAN. See "Configuring
PVCs" on page 3-9 for more details.

Bridging and Routing Over ATM Ports

The ATM module supports bridging and routing across ATM PVCs. Frames can be
forwarded across ATM PVCs using either bridged or routed protocol encapsulations as
defined in IETF RFC 2648/1483. When using the bridged protocol encapsulation, the
ATM module forwards the entire Ethernet frame (except the Frame Check Sequence)
across an ATM PVC. The ATM PVC looks like an Ethernet segment to the rest of the
switch. The Ethernet frame can carry any protocol including IP, IPX, and MPLS, and it
can also include 802.1Q and 802.1p tags. The ATM module can also use the routed
protocol encapsulation for sending IP packets across an ATM PVC. When using the
routed protocol encapsulation, the ATM module strips the Ethernet header and only
forwards the IP datagram across the ATM PVC, resulting in improved throughput for
IP packets.
Before packets can be forwarded over ATM ports, at least one PVC must be configured
on the port and mapped to a VLAN using the
PVC must be mapped to one or more VLANs and each mapping must be designated to
use the bridged protocol encapsulation (using the
atm add pvc
keywords in the
simultaneously used on a PVC as long as they are associated with different VLANs.
ExtremeWare supports up to 500 routed VLANs and 3000 total VLANs in the
Asynchronous Transfer Mode (ATM) Module Installation and User Guide
command) or the routed protocol encapsulation (using the
config atm add pvc
Basic ATM Module Configuration Information
config atm add pvc
config atm add pvc
keywords in the
encap l2
command). Both encapsulations can be
command. Each
config
encap ip
3-3