Here at Zacks, our focus is on the proven Zacks Rank system, which emphasizes earnings estimates and estimate revisions to find great stocks. Nevertheless, we are always paying attention to the latest value, growth, and momentum trends to underscore strong picks.Considering these trends, value investing is clearly one of the most preferred ways to find strong stocks in any type of market. Value investors use a variety of methods, including tried-and-true valuation metrics, to find these stocks.Luckily, Zacks has developed its own Style Scores system in an effort to find stocks with specific traits. Value investors will be interested in the system's "Value" category. Stocks with both "A" grades in the Value category and high Zacks Ranks are among the strongest value stocks on the market right now.One stock to keep an eye on is Ciena (CIEN). CIEN is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock is trading with a P/E ratio of 17.84, which compares to its industry's average of 19.33. CIEN's Forward P/E has been as high as 19.65 and as low as 12.15, with a median of 15.95, all within the past year.Investors should also note that CIEN holds a PEG ratio of 1.11. This popular figure is similar to the widely-used P/E ratio, but the PEG ratio also considers a company's expected EPS growth rate. CIEN's industry currently sports an average PEG of 1.21. CIEN's PEG has been as high as 1.20 and as low as 0.70, with a median of 0.93, all within the past year.These figures are just a handful of the metrics value investors tend to look at, but they help show that Ciena is likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, CIEN feels like a great value stock at the moment.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Ciena Corporation (CIEN): Free Stock Analysis Report To read this article on Zacks.com click here.