EDS-510A Series User’s Manual
Featured Functions
3-41
Head Role
Setting
Description
Factory Default
Head Port
Select any port of the EDS to be the head
port.
port G2
Member Port
Select any port of the EDS to be the
member port.
port G3
Member Role
Setting
Description
Factory Default
1
st
Member port
Select any port of the EDS to be the 1
st
member port
port G2
2
nd
Member port
Select any port of the EDS to be the 2
nd
member port
port G3
Tail Role
Setting
Description
Factory Default
Tail Port
Select any port of the EDS to be the tail
port.
port G2
Member Port
Select any port of the EDS to be the
member port.
port G3
The STP/RSTP Concept
Spanning Tree Protocol (STP) was designed to help reduce link failures in a network, and provide
protection from loops. Networks that have a complicated architecture are prone to broadcast
storms caused by unintended loops in the network. Moxa EDS-510A’s STP feature is disabled by
default. To be completely effective, you must enable RSTP/STP on every EDS-510A connected to
your network.
Rapid Spanning Tree Protocol (RSTP) implements the Spanning Tree Algorithm and Protocol
defined by IEEE Std 802.1w-2001. RSTP provides the following benefits:
The topology of a bridged network will be determined much more quickly compared to STP.
RSTP is backward compatible with STP, making it relatively easy to deploy. For example:
Defaults to sending 802.1D style BPDUs if packets with this format are received.
STP (802.1D) and RSTP (802.1w) can operate on different ports of the same EDS-510A.
This feature is particularly helpful when EDS-510A ports connect to older equipment,
such as legacy switches.
You get essentially the same functionality with RSTP and STP. To see how the two systems differ,
see the
Differences between RSTP and STP
section in this chapter.
NOTE
The STP protocol is part of the IEEE Std 802.1D, 1998 Edition bridge specification. The
following explanation uses bridge instead of switch.