Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of communications networker Ciena (Nasdaq: CIEN) jumped as much as 10.1% on big, big trading volume before settling back at a smaller 2.5% gain.

So what: This jump is a bit of a shocker, because last night's fourth-quarter report wasn't exactly the stuff dreams are made of. Sales grew 9% year over year to $456 million, just ahead of analyst targets, but $0.03 of adjusted earnings per share came up short, and the next-quarter outlook wasn't overly optimistic.

Now what: Sometimes it's more important how you say something than what you're saying; CEO Gary Smith said that his company is taking market share in a period that's holding down sector rivals from JDS Uniphase (Nasdaq: JDSU) to Alcatel-Lucent (NYSE: ALU). Moreover, Ciena reported positive operating cash flows, which has been a goal of Smith's for the past two years. Driven by mobile computing and digital video, high-speed networking will be in serious demand for the next five to 10 years, and Ciena looks poised to capitalize on this outsized opportunity.

Interested in more info about Ciena? Add it to My Watchlist.

Fool contributor Anders Bylund holds no position in any of the companies mentioned. We Fools don't all hold the same opinion, but we all believe that considering a diverse range of insights makes us better investors. Check out Anders' holdings and bio, or follow him on Twitter and Google+. We have a disclosure policy.