DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet User Manual
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Layer 2 Protocol Tunneling Setttings
This window allows users to configure Layer 2 protocol tunneling on the Switch.
To view this window, click
L2 Features > VLAN > Layer 2 Protocol Tunneling Settings
, as shown below.
Figure 4- 27 Layer 2 Protocol Tunneling Settings window
The fields that can be configured are described below:
Parameter
Description
Layer 2 Protocol
Tunneling State
Enable or disable the Layer 2 Protocol Tunneling state.
Port(s)
The user can select the port numbers that will be included in the Layer 2 Protocol Tunneling
configuration.
Click
Apply
to implement changes made.
Spanning Tree
This Switch supports three versions of the Spanning Tree Protocol: 802.1D STP, 802.1w Rapid STP, and 802.1s
MSTP. 802.1D STP will be familiar to most networking professionals. However, since 802.1w RSTP and 802.1s MSTP
has been recently introduced to D-Link managed Ethernet switches, a brief introduction to the technology is provided
below followed by a description of how to set up 802.1D STP, 802.1w RSTP and 802.1s MSTP.
802.1s MSTP
Multiple Spanning Tree Protocol, or MSTP, is a standard defined by the IEEE community that allows multiple VLANs
to be mapped to a single spanning tree instance, which will provide multiple pathways across the network. Therefore,
these MSTP configurations will balance the traffic load, preventing wide scale disruptions when a single spanning tree
instance fails. This will allow for faster convergences of new topologies for the failed instance. Frames designated for
these VLANs will be processed quickly and completely throughout interconnected bridges utilizing any of the three
spanning tree protocols (STP, RSTP or MSTP).
This protocol will also tag BPDU packets so receiving devices can distinguish spanning tree instances, spanning tree
regions and the VLANs associated with them. An MSTI ID will classify these instances. MSTP will connect multiple
spanning trees with a Common and Internal Spanning Tree (CIST). The CIST will automatically determine each MSTP
region, its maximum possible extent and will appear as one virtual bridge that runs a single spanning tree.
Consequentially, frames assigned to different VLANs will follow different data routes within administratively
established regions on the network, continuing to allow simple and full processing of frames, regardless of administra-
tive errors in defining VLANs and their respective spanning trees.
Each switch utilizing the MSTP on a network will have a single MSTP configuration that will have the following three
attributes: