MEN Mikro's G304 is an unmanaged 3U Ethernet switch implemented as a CompactPCI® Serial board. It occupies one peripheral slot, using a 4 HP front panel with 4 Gigabit Ethernet ports on RJ45 connectors, and one direct Ethernet connection to the CPU card using PCI Express® on P1. Options include M12 front connectors, and a P6 connector to extend the number of Ethernet channels available on the board to six.
The G304 supports full-duplex and half-duplex operation with auto-negotiation, high-speed nonblocking store-and-forward switching, Quality of Service (QoS) support with four traffic classes IEEE 802.1p. Its built-in test mechanisms make the G304 an even more reliable component in the communication system. In addition, the switch can act as Power over Ethernet Plus (PoE+) Power Sourcing Equipment (PSE), supplying other devices on all ports with up to 30 W (class 0, 1, 2, 3, 4) per port for power according to IEEE 802.3 Section 2 - Type 1 and 2 (formerly known as IEEE 802.3at). The maximum power available for one G304 is limited to 60 W, according to CPCI-S.0 specification.
By using an application-specific configuration EEPROM, the G304 can act similarly to a managed switch with fixed settings. This enables features untypical for unmanaged models like 802.1p priority and port based priority, port based VLAN or IEEE 802.1q VLAN IDs.
The board is specifically designed for rugged mobile communication systems. It is therefore, for example, fully compliant with the EN 50155 railway standard, screened for a -40 to +85°C operation temperature and ready for coating.