Hitachi US7070447-001 Permanent Virtual Circuits vs Switched Virtual Circuits, LAN Emulation LANE

Draft Level—Hitachi Confidential

HiSpeed Switch Troubleshooting Guide

Permanent Virtual Circuits vs.

Switched Virtual Circuits

ATM connections can be established manually (Permanent Virtual Circuits) or dynamically (Switches Virtual Circuits). Permanent Virtual Circuits (PVCs) are usually defined for long-term connections and automatically re-established after a network failure. Switched Virtual Circuits (SVCs) uses Q.2931 signaling to define and release connections as needed. Unlike PVCs, SVC connections are not automatically re-established after a network failure.

The HiSpeed switch implements the following ATM services:

❒LAN Emulation (LANE)

❒Classical IP over ATM (CIP)

❒Point-to-Point Bridging (PTOP)

❒Trunking

LAN Emulation (LANE)

LANE emulates a traditional LAN (ie. Ethernet or Token Ring) over ATM by mapping MAC addresses to ATM addresses, connectionless technologies to connection-oriented technologies, and emulating the broadcast nature of LANs.

VLAN = ELAN	VLAN = ELAN
LES/BUS	LES/BUS

OC-3

vci 32

vci 45

OC-3

vci 39

L E C vci 67 vci 32 L E C

Workstation

LECS

Native ATM device

*Every ELAN must have (1) unique LES/BUS pair.

**Valid LEC values range from 0 through 31.

Figure 11-2. ATM LANE

11-2 US7070447-001, Rev 01