Netgear XCM8810 - 8800 SERIES 10-SLOT CHASSIS SWITCH ユーザーズマニュアル
Chapter 18. STP
|
545
NETGEAR 8800 User Manual
STPD VLAN Mapping
Each VLAN participating in PVST+ must be in a separate STPD, and the VLAN number
(VLAN ID) must be the same as the STPD identifier (STPD ID). As a result, PVST+ protected
VLANs cannot be partitioned.
(VLAN ID) must be the same as the STPD identifier (STPD ID). As a result, PVST+ protected
VLANs cannot be partitioned.
This fact does not exclude other non-PVST+ protected VLANs from being grouped into the
same STPD. A protected PVST+ VLAN can be joined by multiple non-PVST+ protected
VLANs to be in the same STPD.
same STPD. A protected PVST+ VLAN can be joined by multiple non-PVST+ protected
VLANs to be in the same STPD.
Native VLAN
In PVST+, the native VLAN must be peered with the default VLAN on NETGEAR devices, as
both are the only VLAN allowed to send and receive untagged packets on the physical port.
both are the only VLAN allowed to send and receive untagged packets on the physical port.
Third-party PVST+ devices send VLAN 1 packets in a special manner. XCM8800 does not
support PVST+ for VLAN 1. Therefore, when the switch receives a packet for VLAN 1, the
packet is dropped.
support PVST+ for VLAN 1. Therefore, when the switch receives a packet for VLAN 1, the
packet is dropped.
When a PVST+ instance is disabled, the fact that PVST+ uses a different packet format
raises an issue. If the STPD also contains ports not in PVST+ mode, the flooded packet has
an incompatible format with those ports. The packet is not recognized by the devices
connected to those ports.
raises an issue. If the STPD also contains ports not in PVST+ mode, the flooded packet has
an incompatible format with those ports. The packet is not recognized by the devices
connected to those ports.
Rapid Spanning Tree Protocol
The Rapid Spanning Tree Protocol (RSTP), originally in the IEEE 802.1w standard and now
part of the IEEE 802.1D-2004 standard, provides an enhanced spanning tree algorithm that
improves the convergence speed of bridged networks. RSTP takes advantage of
point-to-point links in the network and actively confirms that a port can safely transition to the
forwarding state without relying on any timer configurations. If a network topology change or
failure occurs, RSTP rapidly recovers network connectivity by confirming the change locally
before propagating that change to other devices across the network. For broadcast links,
there is no difference in convergence time between STP and RSTP.
part of the IEEE 802.1D-2004 standard, provides an enhanced spanning tree algorithm that
improves the convergence speed of bridged networks. RSTP takes advantage of
point-to-point links in the network and actively confirms that a port can safely transition to the
forwarding state without relying on any timer configurations. If a network topology change or
failure occurs, RSTP rapidly recovers network connectivity by confirming the change locally
before propagating that change to other devices across the network. For broadcast links,
there is no difference in convergence time between STP and RSTP.
RSTP supersedes legacy STP protocols, supports the existing STP parameters and
configurations, and allows for seamless interoperability with legacy STP.
configurations, and allows for seamless interoperability with legacy STP.
RSTP Concepts
This section describes the following important RSTP concepts: