IBM SG24-4817-00 manual Classical IP CIP, ATM Classical IP using ARP Server

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To avoid having to configure the LES′s address at each endstation, LANE provides for a Lan Emulation Configuration Server (LECS), which LECs can query for their proper LES address. This enables backup LESs to be configured, since should the primary LES fail, the LECS merely has to direct connections to a backup LES without having to change any configuration in the workstation. Although the 8285 ATM Control Point does not contain an LECS, either or both of the internal LECs can be configured to use an external LECS, such as that provided by the IBM Multiprotocol Switched Services Server.

This section was intended only as an overview of LANE. For a more detailed description of these functions, please see IBM 8260 As a Campus ATM Switch, SG24-5003 and ATM Campus Introduction, Planning, and Troubleshooting Overview, GA27-4089.

1.1.4.3 Classical IP (CIP)

Figure 4. ATM Classical IP using ARP Server

Classical IP (RFC 1577) is a protocol-specific VLAN (PVLAN) technology that has been widely adopted in the Internet working community. It provides for layer 3 routing of IP datagrams over an ATM network. In many ways, it is analogous to LANE. For instance, all endstations must register with an address resolution server (called a LES in LANE, but an Address Resolution Protocol (ARP) Server in CIP). Once the endstation is registered with the address resolution server, it is, by definition, part of a virtual broadcast domain (an ELAN in LANE terminology, but a VLAN in CIP, known as a Logical IP Subnet (LIS)). The 8285 ATM Control Point has a single CIP client entity.

Here are the CIP data flows:

6ATM Workgroup Solutions: Implementing the 8285 ATM Switch