EDS-408A/405A Series User’s Manual

Featured Functions

yEach port has a cost that specifies the efficiency of each link. The efficieny 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,

 

1998 Edition

10 Mbps

100

100 Mbps

19

1000 Mbps

4

Path Cost 802.1w-2001 2,000,000 200,000 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:

yThe bridge that should be the Root Bridge. The Root Bridge is the central reference point from which the network is configured.

yThe Root Path Costs for each bridge. This is the cost of the paths from each bridge to the Root Bridge.

yThe identity of each bridge’s Root Port. The Root Port is the port on the bridge that connects to the Root Bridge via the most efficient path; in other words, the port connected to the Root Bridge via the path with the lowest Root Path Cost. The Root Bridge, however, does not have a Root Port.

yThe identity of the Designated Bridge for each LAN segment. The Designated Bridge is the bridge with the lowest Root Path Cost from that segment. If several bridges have the same Root Path Cost, the one with the lowest Bridge Identifier becomes the Designated Bridge. Traffic transmitted in the direction of the Root Bridge will flow through the Designated Bridge. The port on this bridge that connects to the segment is called the Designated Bridge Port.

STP Configuration

After all the bridges on the network agree on the identity of the Root Bridge, and all other relevant parameters have been established, each bridge is configured to forward traffic only between its Root Port and the Designated Bridge Ports for the respective network segments. All other ports are blocked, which means that they will not be allowed to receive or forward traffic.

STP Reconfiguration

Once the network topology has stabilized, each bridge listens for Hello BPDUs transmitted from the Root Bridge at regular intervals. If a bridge does not receive a Hello BPDU after a certain interval (the Max Age time), the bridge assumes that the Root Bridge, or a link between itself and the Root Bridge, has gone down. This will trigger the bridge to reconfigure the network to account for the change. If you have configured an SNMP trap destination, when the topology of your network changes, the first bridge to detect the change sends out an SNMP trap.

Differences between RSTP and STP

RSTP is similar to STP, but includes additional information in the BPDUs that allow each bridge to confirm that it has taken action to prevent loops from forming when it decides to enable a link to a neighboring bridge. Adjacent bridges connected via point-to-point links will be able to enable a link without waiting to ensure that all other bridges in the network have had time to react to the change. The main benefit of RSTP is that the configuration decision is made locally rather than network-wide, allowing RSTP to carry out automatic configuration and restore a link faster than STP.

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Moxa Technologies EDS-405A Differences between Rstp and STP, Port Speed Path Cost 802.1D Edition, STP Configuration
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EDS-405A, EDS-408A specifications

Moxa Technologies has established itself as a leader in networking solutions, particularly for industrial applications. Among their cutting-edge products is the 405A Series, specifically the EDS-408A model, which exemplifies Moxa's commitment to performance, reliability, and versatility in industrial Ethernet switches.

The EDS-408A is an 8-port industrial Ethernet switch that offers an impressive array of features and capabilities designed to meet the demands of harsh environments. One of its main highlights is the ability to support both 10/100 Mbps Fast Ethernet and Gigabit Ethernet connections, providing users with the flexibility to integrate a range of devices within their network. Its robust design ensures that it operates seamlessly in extreme conditions, with a wide operating temperature range from -40 to 75 degrees Celsius.

The EDS-408A is built to support an array of networking topologies. It features advanced Ethernet switching technologies that enable fast and efficient data transfer while minimizing latency. The device is equipped with wire-speed forwarding capabilities, which is vital for maintaining high performance in heavy network traffic scenarios.

Another key feature of the EDS-408A is its redundancy support. The switch incorporates various redundancy protocols, including Rapid Spanning Tree Protocol (RSTP) and MRP (Media Redundancy Protocol), which enhance network reliability by allowing quick recovery in the event of a failure. This ensures continuous network uptime, which is critical for industrial applications.

Furthermore, Moxa Technologies has adopted an user-friendly web-based management interface in the EDS-408A, simplifying the configuration and monitoring process. This allows system administrators to easily manage settings, monitor traffic, and troubleshoot issues in real time. Additionally, the switch supports SNMP (Simple Network Management Protocol) for remote monitoring and management, enabling organizations to keep their networks optimized.

Security is another paramount feature of the EDS-408A. It includes built-in security mechanisms such as port security, VLAN, and access control lists (ACLs), which help safeguard sensitive network segments from unauthorized access.

In conclusion, Moxa Technologies' EDS-408A model from the 405A Series is a robust and feature-rich industrial Ethernet switch designed for demanding environments. With its support for various network protocols, redundancy features, user-friendly management, and enhanced security, the EDS-408A stands out as a reliable solution for organizations looking to enhance their industrial networking capabilities.
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