Chapter 2 Using the LFH Hub
2.1 Packing Checklist
Your LFH package should contain the following:
✓An LFH4-M or LFH8-M Mini Fast Hub
✓Mounting brackets and screws
✓External AC/DC power adapter (120VAC or 220VAC)
✓Installation Guide
If any of these items are missing, contact your dealer immediately.
2.2 Planning 100BASE-TX Networks
100BASE-TX networks need to be planned out slightly differently from 10BASE-T networks, because new hubs and new wiring configurations are necessary. (10BASE-T hubs are incapable of sending or receiving data at 100Mbps, so a 100BASE-TX network requires a 100BASE-TX hub.)
100BASE-TX supports a maximum length of 100 meters from a network station to a hub. The total network diameter (the maximum cable distance between any two stations on the network) is 205 meters for 100BASE-TX, as opposed to 500 meters for 10Mbps Ethernet. Because 100BASE-TX sends signals ten times faster than 10BASE-T, the collision window (the time during which the network can detect a collision between packets) is reduced to one-tenth the duration of the 10BASE-T collision window, making the maximum network diameter smaller.
In a repeater environment, 100BASE-TX only allows a single layer of cascaded hubs.
Switching hubs, such as LantronixÕs LSW8FA, may increase the network diameter for 100BASE-TX networks by buffering data packets. Each port can be connected to a separate LAN segment, each with a maximum diameter of 205 meters, thereby increasing the overall 100BASE-TX network diameter.
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