Cabletron Systems 04-0053-01 Lane Over WAN Circuits, Physical Versus Logical BUS Multicasting

Creating an Emulated LANIP Over ATM and LANE

In the following example, a client is identified by its ATM address and IP address, and associates it with ELAN number 1.

SmartSwitch # add lecselanlec
AtmAddress()	: 39:00:00:00:00:00:00:00:00:00:44:55:66:11:22:33:44:55:66:00
MACAddress/RouteDesc()	:	— No MAC address is specified
Layer3Address[IP]()	: 204.123.91.7
ELANNumber(0)	: 1	— ELAN is specified by ELAN number
TLVSet()	:	— No TLV set is specified

SmartSwitch #

If the currently defined ELAN policies use either Best Effort or By ATM Address and/or By IP Address, the client with the ATM address and IP address specified above will be assigned to ELAN 1.

Note To specify a TLV set with the add lecselanlec command, the TLV set must currently exist. Use the add lecstlvset command to create a TLV set. For detailed information on the add lecstlvset command, see the SmartSwitch ATM Reference Manual.

2.2.6LANE Over WAN Circuits

SmartSwitch ATM switches allows LANE server support across WAN ATM connections. In this type of configuration, a SmartSwitch running LANE services (LECS, LES and BUS) resides on one side of an ATM WAN, while SmartSwitch ATM switches on the other side of the WAN provide connectivity for LANE clients across the WAN to the LANE server. In effect, the connections created between the LANE server and its clients “tunnel” across the ATM WAN’s PVP connections.

Note See Chapter 5, "Virtual Ports and Static Connections." for information about PVP connections and virtual ports.

Physical Versus Logical BUS Multicasting

When connecting to LANE services across an ATM WAN, it’s important to consider the WAN-to-LAN connectivity. Typically, PVPs (assigned by services provides) are terminated on the end switches using virtual ports. In a simple configuration, with a single PVP terminated by a single virtual port at each end, clients submitting ELAN join requests can traverse the WAN and reach LANE services. Likewise, the LANE servers (especially the BUS) can reply back across this single connection. In effect, all traffic between the end switches is “tunneled” across the PVP WAN connection. In this case, the BUS creates its point-to-multipoint client connections using physical multicasting across the WAN (see Figure 2-1).

2-14 SmartSwitch ATM User Guide