Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Jumping Juniper Networks (Nasdaq: JNPR), Batman! Juniper shares have popped by as much as 11% today after wireless carrier AT&T (NYSE: T) officially dropped its $39 billion bid to buy T-Mobile.

So what: The falling through of the deal can be seen as a positive development for networking equipment makers, like Juniper and Ciena (Nasdaq: CIEN), as it frees up the carriers' budgets. As AT&T's capital spending ramps up, which is expected early next year, networking companies stand to cash in.

Now what: AT&T had been cutting back and putting its weight behind trying to get the T-Mobile deal through, and with that overhang gone, AT&T is expected to resume building up its wireless network. Juniper, Ciena, Cisco Systems (Nasdaq: CSCO), and F5 Networks (Nasdaq: FFIV) are expected to indirectly benefit from Ma Bell's big spending. Morgan Stanley analyst Ehud Gelblum believes communication equipment makers could see some upside into earnings while valuations are at multiyear lows.

Interested in more info on Juniper Networks? Add it to your watchlist by clicking here.