Atm Addressing For Lan Emulation - Cabletron Systems SmartCell 6A000 User Manual

    
Configure the ATM interface or adapter for all end nodes and edge devices. Typically, configuration
6.
consists of specifying LAN Emulation as the protocol, assigning the device an IP address that
corresponds to the subnet of the switch's client, and indicating that you want the device to use the
Well Known LECS Address or the ILMI acquired LECS address as the address for the LECS.
Messages are displayed on the console as each end device registers with the LES and BUS. You can
7.
check connectivity by pinging between end nodes.
Your ELAN is now operational. Additional ELANs can be created in the same way. See Chapter 4, "Switch
Administration." for information about SmartCell 6A000 switch operations and maintenance.
Note While it is possible for a single ELAN on the SmartCell 6A000 switch to support
multiple subnets, in general, switch performance is best and management easiest
when the "One-subnet-per-ELAN" rule is observed.
3.2.1

ATM Addressing for LAN Emulation

The SmartCell 6A000 provides a default format for ATM addresses used by LAN emulation. The default format is
constructed as follows:
netprefix + the MAC address of the device + a Selector Byte
Where the netprefix is constructed from
39 + nine zero bytes + the last three bytes of the switch's MAC address
The Selector Byte specifies to whom the ATM address belongs.
•
00 = LEC
•
01 = LECS
•
02 = LES or BUS
For instance, if the switch's MAC address is 00:20:D4:14:41:80, then the 20-byte ATM address of the LECS is:
39:00:00:00:00:00:00:00:00:00:14:41:80:00:20:D4:14:41:80:01
Where
•
39:00:00:00:00:00:00:00:00:00:14:41:80 = netprefix
•
00:20:D4:14:41:80 = the switch's MAC address
•
01 = the Selector Byte indicating that this is the LECS
Additionally, within both the LES and BUS addresses, the byte that corresponds to the last byte of the MAC address
is summed with the ELAN number. For example, the ATM address of the LESs on ELAN000, ELAN001, and
ELAN010 are
•
LES for ELAN000 = 39:00:00:00:00:00:00:00:00:00:14:41:80:00:20:D4:14:41:80:02
•
LES for ELAN001 = 39:00:00:00:00:00:00:00:00:00:14:41:80:00:20:D4:14:41:81:02
•
LES for ELAN010 = 39:00:00:00:00:00:00:00:00:00:14:41:80:00:20:D4:14:41:8A:02

   
SmartCell 6A000 User Guide 3-5