UPDATE: Citigroup Upgrades Artista Networks On 'Sizable Q2 Beat'

In a note released Friday, Citigroup analyst Ehud Gelblum upgraded shares of Arista Networks ANET from Neutral to Buy and raised the price target from $70 to $90.

Gelblum's upgrade is based on increased confidence from Arista's second quarter beat that the company will be able to sustain operating margins in the ~20 percent range for 2014. He noted the prior Neutral rating was reflected an estimate of 12 percent.

Gelblum wrote, "We believe Arista remains well positioned to gain share in the DC switching market as cloud providers remain at the cusp of a collective multi-year global data center build-out and feel more comfortable with a higher multiple."