1. ATM LAN Emulation (LANE) Trebea-Corda Cristian Technical University, Cluj-Napoca

2. LAN Emulation (LANE) What is LAN Emulation “…makes an ATM interface look like one or more LAN interfaces” (CISCO LANE Overview) Specified in LAN Emulation over ATM (ATM_FORUM 94-0035) Approved in Feb 1995, as LE V 1.0 The reason and goals of LANE Interconnectivity and transparency

3. Types of LANE connectivity All ATM connections LAN to ATM connections LAN to LAN connections (with ATM backbone)

4. LAN emulated characteristics Connectionless Service Multicast addresses Multicast MAC MAC driver interfaces in ATM stations Emulated LANs Interconnection With Existing LANs

5. Architecture of LANE

6. Components of LANE LAN Emulation client software Controlls an ATM interface LAN Emulation Service Three servers Emulated LANs Ethernet/IEEE 802.3 Token Ring/IEEE 802.5

7. LANE Clients Role Ethernet/Token Ring frames to AAL5 Uses Virtual Channel Connections (VCC) MAC for each ATM interface

8. LANE Client Protocol Elements Transmitted frames (with AAL5 frames) Ethernet II (DIX) IEEE 802.2/IEEE 802.3 Ethernet Token Ring

9. LANE Service Handles multiple LECs LUNI (LANE User Network Interface) Three components LAN Emulation Configuration Service (LECS) LAN Emulation Server (LES) Broadcast/Unknown Server (BUS)

10. LANE Client Initialization Connect to LECS ILMI Anycast address reserved for LECS Use a special PVC, with VPI/VCI 0/17 Interact with LECS Send ATM and MAC address, LAN type and supported frame size Receive LES address, LAN type and frame size to be used

11. LANE Client Initialization Communication with LES Point-to-point connection (Control Direct VCC) JOIN REQUEST control frame JOIN RESPONSE control frame Connection is maintained in point-to- multipoint list

12. LANE Client Initialization Communication with LES JOIN REQUEST Client ATM and MAC addresses Type of LAN and maximum frame size to be supported Indication if the client acts as proxy for remote MACs (it is switch or edge device) The name of ELAN wished to join (if known)

13. LANE Client Initialization Communication with LES JOIN RESPONSE Similar fields with JOIN REQUEST Mandatory fields Type of LAN Maximum frame size Name of ELAN Assigns a LANE Client ID (LECID)

14. Connecting to the BUS LEC requests to the LES the ATM broadcast address for all 1’s MAC address The reply is the BUS address

15. Address Resolution A LANE Client needs to know either The peer LANE Client ATM address The proxy edge device ATM address Steps of communication LE-ARP request to LES The LES either forwards or responds with the address The connection is opened

16. Quick Sends and Flushing An alternative to LE-ARP is BUS After broadcast, new connection can be opened LE_FLUSH_REQUEST, path clear request LE_FLUSH_RESPONSE, path cleared

17. Operating with Higher Layer Protocols After finding the peer MAC address Use BUS Ask the LES the peer ATM, for connection opening IETF proposes ATMARP Server

18. Next Hop Resolution Protocol ATMs as non-broadcast multi-access network (NBMA) NHRP finds the ATM address of the best next hop

19. Multiprotocol Over ATM MPOA device ATM interface, LANE software, MPOA client software MPOA server Router containing MPOA server software Shortcut ATM VCC, used instead of the default path A MPOA device requests shortcut information from a MPOA server Shortcuts are opened only at steady traffic

20. References http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/1 13ed_cr/switch_c/xcovlane.htm http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/1 13ed_cr/switch_c/xcovlane.htm http://www.iphase.com/docs/whitepapers/lanemul.cfm http://www.rad.com/networks/1996/atmle/atmle.htm http://www.ece.wpi.edu/courses/ee535/hwk96/hwk5cd96/cobden/cob den.html http://www.ece.wpi.edu/courses/ee535/hwk96/hwk5cd96/cobden/cob den.html http://www.protocols.com/pbook/lane.htm http://www.atmforum.org http://cell-relay.indiana.edu/cell-relay/ Dr. Sidnie Feit – “Wide Area High Speed Networks”