Cabletron Systems STH 24 STH-24 User Manual

Also see for SmartSwitch 9000: Reference guide Appendix Appendix Appendix User guide

Contents

Cabletron Systems STH 24 STH-24 User Manual Manual pdf 24 page image

Operation3-4Flexible Network Bus (FNB)The FNB consists of two dual FDDI networks, the FNB-1 and FNB-2, providingup to 400 Mbps of data bandwidth. These FDDI networks are 100% ANSIFDDI-compliant supporting SMT (version 7.3), MAC, PHY, and PMD standards.This allows the FNB to traverse multiple SmartSwitch 9000 hubs, or connect toany ANSI FDDI-compliant device, through standard A/B port connections, usingthe FDDI repeater module.System Management BusesThere are two management channels within the SmartSwitch 9000 system: theSMB-1 and the SMB-10. These buses provide out-of-band management and inter-module management communication.SMB-1 BusThe SMB-1 is a 1Mbs management bus located within the SmartSwitch 9000. Thisbus is utilized by all diagnostic controllers in the system including connectivitymodules, power supply modules and the environmental module. The SMB-1transports inter-chassis information between system components, such as powerand environmental information, as well as diagnostic messages. Periodicloop-back tests are preformed by all modules that share this bus to ensure thevalidity of SMB-1. In the event a failure is detected on SMB-1, the SMB-10 may beused as an alternate communication channel.SMB-10 BusThe SMB-10 is a 10Mbs management bus located within the SmartSwitch 9000that is also used for inter-chassis communication of modules, as well as serving asan out-of-band management channel into the SmartSwitch 9000. The SMB-10 isexternalized from the chassis via an optional Ethernet Port Interface Module(EPIM) located on the front of the Environmental Module. Through an EPIMconnection, full SNMP management of the SmartSwitch 9000 is available out-of-band from user data. Modules that share the SMB-10 bus periodically send outloop-back packets to ensure the validity of SMB-10. In the event a fault is detectedon the SMB-10, the SMB-1 can be used as an alternate communication channel bythe modules.