1000Base SX is a single mode fiber-optic connection.
More information can be found here:
http://en.wikipedia.org/wiki/Gigabit_Ethernet
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1 Gbps
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One can find more information about 1000base SX on the Cisco
website. They have information about the product and data sheets
with more details. One can purchase it from Amazon.
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The Cisco 1000BASE SX GBIC is an interchangable input/output
device that connects to a gigabit ethernet port/slot, linking the
port with the fiber-optic network.