GE ML1200 instruction manual Status LEDs, Auto-Cross Mdix and Auto-negotiation, for RJ-45 ports

OPERATION CHAPTER 4: OPERATION

4.1.1.2 Address Learning

All Multilink ML1200 units have address table capacities of 4K node addresses suitable for use in larger networks. They are self-learning, so as nodes are added, removed or moved from one segment to another, the ML1200 Switch automatically keeps up with node locations.

An address-aging algorithm causes least-used addresses to fall out in favor for frequently- used addresses. To reset the address buffer, cycle power down-and-up.

4.1.2Status LEDs

For Multilink ML1200 models (/ML1200) :

PWR: Power LED, ON when external power is applied to the unit.

LK: Steady ON, Link status for 10 Mbps and 100Mbps operation.

ACT: ON with port activity for 10 Mbps and 100Mbps operation.

F/H: Full / Half duplex LED, ON when the port is running full duplex, OFF for half duplex.

100/10: Speed LED, ON when the speed is 100Mbps , OFF when the speed is 10 Mbps

4.1.3Auto-Cross (MDIX) and Auto-negotiation, for RJ-45 ports

The RJ-45 ports independently support auto-cross (MDI or MDIX) in auto-negotiation mode and will work properly with all the other connected devices with RJ-45 ports whether they support Auto-negotiation (e.g 10Mb Hub, media converter) or fixed mode at 10Mb or 100Mb Half/Full Duplex(managed switch) or not. No cross-over cable is required while using the ML1200’s copper port to other devices. Operation is according to the IEEE 802.3u standard.

The Managed ML1200’s Fast Ethernet copper ports can be set for either fixed 100Mb speed or for 10/100 F/H N-way auto-negotiation per the IEEE802.3u standard. The selection is made via MNS software. The factory default setting is for auto-negotiation. At 10Mb or 100Mb-fixed speed, the user may select half- or full-duplex mode by management Software for each RJ-45 port separately.

One frequently-used application for the Managed Multilink ML1200 Switch copper ports is to connect one of them using a fiber media converter to another Switch in the network backbone, or to some other remote 100Mb device. In this case, it is desirable to operate the fiber link at 100Mb speed, and at either half- or full duplex mode depending on the capabilities of the remote device. Standard commercially available Fast Ethernet media converters mostly do not support auto-negotiation properly, and require that the switched port to which they are connected be at the 100Mb fixed speed. Attachments to a 10/100 auto-negotiation port typically will not work properly. The ML1200 Switch’s RJ-45 ports handle this situation by configuring the ports as per desired through MNS software port settings and can check the port status of each port after the change.

When Multilink ML1200 RJ-45 copper ports are set for auto-negotiation and are connected to another auto-negotiating device, there are 4 different speed and F/H modes possible depending on what the other device supports. These are: (1) 100Mb full-duplex, (2) 100Mb half-duplex, (3) 10 Mb full-duplex and (4) 10 Mb half-duplex.

4–2 MULTILINK ML1200 MANAGED FIELD SWITCH – INSTRUCTION MANUAL