For industrial automation applications, redundancy is an important issue to help increase the reliability of your system. MOXA EtherDevice??Managed Redundant Switch EDS-408A/405A sereis comes equipped with a redundant network protocol called Turbo Ring that was developed by Moxa. Turbo Ring gives users an easy way to establish a redundant Ethernet network, and with its ultra high-speed recovery time, once any segment of your network is disconnected, your automation system will be back to normal in less than 300 ms.

For some systems, it may not be convenient to connect all devices in the system to create one BIG redundant ring, since some devices could be located at a remote site. Turbo Ring's ring Coupling function helps you separate those distributed devices into different smaller redundant rings, but in such a way that they can still communicate with each other.

A VLAN is a group of devices that can be located anywhere on a network, but communicate as if they are on the same physical segment. VLANs can be used to segment your network without being restricted by physical connections? limitation imposed by traditional network design. Besides, since all automation systems incorporate sensitive devices that must be protected from unauthorized access, it is very important to have some type of authentication system set up that only allows authorized users to access the system. If devices belong to different VLANs, they cannot communicate with each other, providing extra security and protection from unwanted invasion or traffic.

Quality of Service (QoS) provides a traffic prioritization capability to ensure that important data is delievered consistently and predictably. EDS-408A/405A series can inspect IEEE802.1p/1Q layer 2 CoS tags, and even layer 3 TOS information, to provide a consistent classification of the entire network. EDS-408A/405A series' QoS capability improves your industrial network's performance and determinism for mission critical applications.

Any single device on a network should not have unlimited bandwidth, particularly when it malfunctions. The most well-known problem is the broadcast storms caused by setting up the wrong topology, or by devices that malfunction. The EDS-408A/405A series not only prevents broadcast storms, but also can configure the ingress/egress rate of unicast/multicast/broadcast packets, and in this way give administrators full control of limited bandwidth to prevent unpredictable faults.

In some cases, a network is so large that it is difficult to achieve the expected level of communications. Industrial communications applications use more of a command-response style than the file-transfer style used in office network environments. This means that when first setting up an industrial Ethernet network, control engineers may need to use a second port to monitor the actual activity between their devices and computer host. EDS-408A/405A series' mirroring port function helps to ensure that the system behaves as expected.

Industrial Ethernet devices are often located at the endpoints of a system. Such devices cannot always know what's happening elsewhere on the network. This means that industrial Ethernet switches that connect these devices must take responsibility for providing system maintainers with real-time alarm messages. Even when control engineers are out of the control room for an extended period of time, they can still be informed of the status of devices almost instantaneously when exceptions occur. The traditional way of determining device status is to poll devices periodically, but this is not ?eal-time??enough, and is not very efficient. Warning messages must be actively triggered by events. To take care of these requirements, industrial Ethernet Switches need features such as warning by email or relay output. The EDS-408A/405A series can send out a warning e-mail when an exception is detected, providing system managers with realtime alarm messages. The EDS-408A/405A series also provides one relay output that can be set up to indicate events with different importance to notify or warn engineers in the field, so the engineer can use the appropriate emergency maintenance procedures to respond quickly to higher priority messages.

To reduce the effort required to configure IP addresses repeatedly, the EDS-408A/405A series comes equipped with DHCP/BootP server and RARP protocol to set up IP addresses of Ethernet-enabled devices automatically.

The EDS-408A/405A series is easily configured over the network by web browser, Telnet console, or a Moxa provided Windows utility. In addition, Moxa's Batch Configurator can also be used to store and copy configuration parameters to multiple EDS-408A/405A units simultaneously.