MRV Communications MR2228-S2C User Manual

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Figure 2-4. Making VLAN Connections 
Note: When connecting to a switch that does not support IEEE 802.1Q VLAN 
tags, Use untagged ports. 
Application Notes 
1. Full-duplex operation only applies to point-to-point access (such as when a 
switch is attached to a workstation, server or another switch). When the switch is 
connected to a hub, both devices must operate in half-duplex mode. 
2. Avoid using flow control on a port connected to a hub unless it is actually 
required to solve a problem. Otherwise back pressure jamming signals may 
degrade overall performance for the segment attached to the hub. 
3. As a general rule the length of fiber optic cable for a single switched link should 
not exceed: 
• 1000BASE-SX: 550 m (1805 ft)    for multimode fiber. 
• 1000BASE-LX: 5 km (3.1 miles)  for singlemode fiber. 
• 1000BASE-LH: 70 km (43.5 miles)  for singlemode fiber. 
However, power budget constraints must also be considered when calculating the 
maximum cable length for your specific environment.