EDS-510A Series User’s Manual

Featured Functions

What happens if a link failure is detected? As shown in next figure, the STP process reconfigures the network so that traffic from LAN segment 2 flows through Bridge B.

Bridge A

LAN 1

Bridge B

LAN 2

Bridge C

LAN 3

STP will determine which path between each bridged segment is most efficient, and then assigns a specific reference point on the network. When the most efficient path has been identified, the other paths are blocked. In the previous 3 figures, STP first determined that the path through Bridge C was the most efficient, and as a result, blocked the path through Bridge B. After the failure of Bridge C, STP re-evaluated the situation and opened the path through Bridge B.

How STP Works

When enabled, STP determines the most appropriate path for traffic through a network. The way it does this is outlined in the sections below.

STP Requirements

Before STP can configure the network, the system must satisfy the following requirements:

yCommunication between all the bridges. This communication is carried out using Bridge Protocol Data Units (BPDUs), which are transmitted in packets with a known multicast address.

yEach bridge must have a Bridge Identifier that specifies which bridge acts as the central reference point, or Root Bridge, for the STP system—bridges with a lower Bridge Identifier are more likely to be designated as the Root Bridge. The Bridge Identifier is calculated using the MAC address of the bridge and a priority defined for the bridge. The default priority of EDS-510A is 32768.

yEach port has a cost that specifies the efficiency of each link. The efficiency cost is usually determined by the bandwidth of the link, with less efficient links assigned a higher cost. The following table shows the default port costs for a switch:

Port Speed

Path Cost 802.1D,

Path Cost

 

1998 Edition

802.1w-2001

10 Mbps

100

2,000,000

100 Mbps

19

200,000

1000 Mbps

4

20,000

STP Calculation

The first step of the STP process is to perform calculations. During this stage, each bridge on the network transmits BPDUs. The following items will be calculated:

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Moxa Technologies EDS-510A user manual How STP Works, STP Requirements, Port Speed Path Cost 802.1D Edition 802.1w-2001
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EDS-510A, Moxa EtherDevice Switch specifications

Moxa Technologies is a leader in providing innovative networking solutions for industrial applications, and one of its standout products is the Moxa EtherDevice Switch, EDS-510A. This robust, managed Ethernet switch is specifically designed for reliable performance in challenging industrial environments, making it an ideal choice for various applications, including automation, transportation, and power generation.

The EDS-510A features five 10/100Base-TX Fast Ethernet ports, allowing flexibility in connecting multiple devices. Additionally, it offers two Gigabit Ethernet ports for uplink, enabling high-speed connections to aggregation switches or routers. The switch supports both redundant power inputs and a wide operating temperature range of -40 to 75 degrees Celsius, ensuring continuity of service even in extreme conditions.

One of the key features of the EDS-510A is its support for IEEE 802.3at PoE (Power over Ethernet). This technology allows the switch to deliver power to connected devices such as IP cameras and wireless access points through the Ethernet cable, which simplifies installation and reduces the need for additional power sources. This is especially beneficial in remote locations where power availability may be limited.

The EDS-510A is also equipped with advanced management features that include VLAN support, port mirroring, and QoS (Quality of Service) capabilities. These features enhance network performance and security, enabling users to prioritize critical traffic and segment the network for better control. Moreover, it supports SNMP (Simple Network Management Protocol), allowing for easy integration into existing network management systems.

Another notable characteristic is the switch's rugged design. With a metal housing that provides excellent EMI (Electromagnetic Interference) protection, the EDS-510A can withstand harsh industrial environments. It is also compliant with various industrial standards, reinforcing its suitability for mission-critical applications.

In summary, the Moxa EtherDevice Switch, EDS-510A, is engineered to meet the demands of modern industrial networking. With its combination of PoE capability, advanced management features, and rugged design, it ensures reliable and efficient network performance, making it an excellent choice for organizations looking to enhance their industrial networking infrastructure. Whether deployed in factories, transportation systems, or utility environments, the EDS-510A continues to be a trusted solution for numerous applications.
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