140
C
HAPTER
7: LAN E
MULATION
V
ERSIONS
1.0
AND
2.0
LAN Emulation Server
(LES)
The LAN Emulation Server (LES) coordinates and controls an ELAN. It
provides the central “directory” service of an ELAN to which a LEC can
turn to look up the ATM address of another LEC. The LES directory
contains a table of LAN destinations (
LAN destination
refers to either a
MAC address or a Route Descriptor) together with the ATM addresses of
the LECs that represent them. In order to transmit a data frame to a
particular LAN destination, the LEC sends the data frame to the LEC that
represents that LAN destination. If the LEC does not already know the
destination LEC’s address, it can send the LAN destination to the LES to
look it up (
resolve)
. To populate the LES directory, the LECs may
register
the LAN destination of LAN stations they represent with the LES. Every
Route Descriptor must be registered with the LES.
LANE Services normally reside on a central ATM switch, such as the
CoreBuilder
®
7000, but may also reside on an ATM end station instead.
Broadcast and
Unknown Server
(BUS)
The BUS is the LANE connection service which handles ATM traffic other
than direct transmissions between LECs. It handles the following:
Data sent by a LEC to the broadcast MAC address
All multicast traffic
Initial unicast frames which are sent by a LEC before the data direct
virtual connection to the ATM address has been resolved
Unknown traffic
All broadcast, multicast and unknown traffic to and from a LEC passes
through a single BUS.
The BUS also handles ATM connections and manages its distribution
group.
LAN Emulation
Configuration Server
(LECS)
The LECS assigns individual LAN Emulation Clients to different emulated
LANs. Based on its own programming, configuration database and
information provided by clients, it assigns any client which requests
configuration information to a particular emulated LAN service by giving
the client the LES’s ATM address. This method supports the ability to
assign a client to an emulated LAN based on either the physical location
(ATM address) or the identity of a LAN destination which it is representing
(ELAN name). LECs obtain information from a LECS using the
configuration protocol.
Summary of Contents for CoreBuilder 7000
Page 12: ......
Page 30: ...30 CHAPTER 1 ATM NETWORK BASICS...
Page 32: ...32 CHAPTER 1 ATM NETWORK BASICS...
Page 34: ...34 CHAPTER 1 ATM NETWORK BASICS Figure 8 LANE Network over WAN...
Page 96: ...96 CHAPTER 4 PRIVATE NETWORK TO NETWORK INTERFACE PNNI VERSION 1 0...
Page 184: ...184 CHAPTER 7 LAN EMULATION VERSIONS 1 0 AND 2 0...
Page 206: ...206 CHAPTER 9 DEVICE MANAGEMENT...
Page 222: ...222 APPENDIX A TECHNICAL SUPPORT...
Page 234: ...234 APPENDIX B PROTOCOLS AND INTERFACES...
Page 238: ...238 APPENDIX C COREBUILDER 7000 FAMILY ATM SWITCH SPECIFICATIONS...
Page 242: ...242 APPENDIX D SAFETY INFORMATION...