Design Reference
Table Of Contents
- Contents
- Chapter 1: Introduction
- Chapter 2: New in this release
- Chapter 3: Network design fundamentals
- Chapter 4: Hardware fundamentals and guidelines
- Chapter 5: Optical routing design
- Chapter 6: Platform redundancy
- Chapter 7: Link redundancy
- Chapter 8: Layer 2 loop prevention
- Chapter 9: Spanning tree
- Chapter 10: Layer 3 network design
- Chapter 11: SPBM design guidelines
- Chapter 12: IP multicast network design
- Multicast and VRF-Lite
- Multicast and MultiLink Trunking considerations
- Multicast scalability design rules
- IP multicast address range restrictions
- Multicast MAC address mapping considerations
- Dynamic multicast configuration changes
- IGMPv3 backward compatibility
- IGMP Layer 2 Querier
- TTL in IP multicast packets
- Multicast MAC filtering
- Guidelines for multicast access policies
- Multicast for multimedia
- Chapter 13: System and network stability and security
- Chapter 14: QoS design guidelines
- Chapter 15: Layer 1, 2, and 3 design examples
- Chapter 16: Software scaling capabilities
- Chapter 17: Supported standards, RFCs, and MIBs
- Glossary
RSTP and MSTP provide a global spanning tree parameter, called version, for backward
compatibility with legacy STP. You can configure version to either STP-compatible mode, RSTP
mode, or MSTP mode:
• An STP-compatible port transmits and receives only STP Bridge Protocol Data Units (BPDU).
An RSTP or MSTP BPDU that the port receives in this mode is discarded.
• An RSTP or MSTP port transmits and receives only RSTP or MSTP BPDUs. If an RSTP or
MSTP port receives an STP BPDU, it becomes an STP port. You must manually intervene to
configure this port for RSTP or MSTP mode again. This process is called Port Protocol
Migration.
You must be aware of the following recommendations before you implement MSTP or RSTP:
• The default mode is MSTP. A special boot configuration flag identifies the mode.
• You can lose your configuration if you change the spanning tree mode from MSTP to RSTP
and the configuration file contains VLANs configured with MSTI greater than 0. RSTP only
supports VLANs configured with the default instance 0.
• For best interoperability results, contact your Avaya representative.
Spanning tree
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Network Design Reference for Avaya VSP 4000 Series January 2015
Comments? infodev@avaya.com