Ciena stock up 609% in one year as AI data center demand drives optical networking sales; analyst recommends taking profits at current $77 billion valuation.

Ciena, which makes long-haul optical networking equipment, saw its stock rise 609% over the past year. Cloud providers now account for 42% of the company's revenue, with total revenue growth accelerating to 33% last quarter.

Ciena's 1.6 terabit-per-second product, introduced in 2024, delivers twice the capacity per wavelength with the same power requirements as an 800 gigabit-per-second system, halving the energy cost to transmit data. The company spends about one-fifth to one-quarter of revenue on R&D.

At an enterprise value of about $77 billion, the stock trades for about 58 times 2026 EBITDA expectations. Management expects full-year revenue growth of 28% and operating margin expansion to 18.5% at the midpoint of guidance, but growth is likely to taper as data center build-outs slow.