While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Palo Alto Networks (PANW 4.19%) gained slightly in premarket trading Thursday after Dougherty & Co. initiated coverage on the network security technologist with a buy rating.

So what: Along with the bullish call, analyst Catharine Trebnick planted a price target of $95 on the stock, representing about 19% worth of upside to yesterday's close. So while contrarian traders might be turned off by Palo Alto's price strength over the past year, Trebnick's call could reflect a sense on Wall Street that its operating tailwinds give the stock plenty of room to run.

Now what: Dougherty expects Palo Alto to post revenue growth of 47% and 35% in 2014 and 2015, respectively. "Palo Alto's innovative firewall technology and a highly successful marketing effort (supported by our customer and reseller checks) have helped the company achieve exceptional growth rates and gain market share," said Trebnick. "Palo Alto's strong fundamentals with multiple tailwinds should enable PANW to sustain solid growth rates well above market expectations, including share gains, product cycle benefits (high end appliance) and advanced threat (Wildfire)." With the stock now up more than 40% in 2014 and trading at a price-to-cash flow of 37, however, I'd hold out for a wider margin of safety before betting too heavily on those prospects.