How can the market for endspan Power over Ethernet - in which PoE is supplied via the switch port rather than through a midspan device between the switch and the user - be growing and flat at the same time? That's what happened in 2010, according to market-research firm In-Stat.

The "growing-and-flat" phenomenon really means that total endspan PoE port shipments grew in 2010 versus 2009, but the percentage of PoE ports shipped compared to total ports shipped last year remained steady. "After a sluggish 2009, Cisco's Power over Ethernet port shipments took off in 2010," according to In-Stat industry analyst Brad Shaffer. "Industry wide, shipments of Power over Ethernet ports remained relatively flat in 2010, accounting for about 15.6 percent of total port shipments."

In its report 4Q10 Ethernet Switch Database, In-Stat explains that Cisco saw a 45-percent gain in PoE port shipments in 2010 over 2009. Shaffer says, "While Cisco is by far the market leader in Power over Ethernet shipments, the other top vendors also experienced an increase in shipments. Netgear and HP Networking both also posted impressive gains in Power over Ethernet shipments, rising 36 percent and 33 percent, respectively."

Cisco's 2010 PoE port shipments totaled more than 42 million, dwarfing HP Networking's 6.3 million and Netgear's 1.6 million.

You may also be interested in this article: Maximizing the efficiency of Power over Ethernet. Authored by Microsemi's Sani Ronen, the article explains the benefits of using midspan PoE devices as opposed to the endspan devices discussed in this story.