Arista Networks forecasted better-than-expected sales for the first quarter after results topped consensus estimates in 4Q. Shares spiked 5.2% in Thursday’s extended trading session after closing almost 1% lower on the day. The computer networking company’s 4Q revenues increased 17.4% year-over-year to $648.5 million and exceeded the consensus estimate of $628.93 million. Adjusted earnings surged 8.7% to $2.49 per share and beat the Street estimates of $2.39 per share. Arista Networks’ (ANET) adjusted gross margin was 65%, down from 65.2% year-over-year.