Like some classic rock song that repeats it self over and over on the radio, rumors that Juniper Networks Inc. (Nasdaq: JNPR) is buying Extreme Networks Inc. (Nasdaq: EXTR) are back on the Wall Street airwaves.

One fund manager source, who asked not to be named, says that's what's driven Extreme stock today, which gained $0.21 (4.78%) to $6.40. In fact, Extreme shares traded an unusually large volume of 2.5 million shares, compared to an average of 1.9 million.

Here's a quick regurgitation of the story line: Juniper is moving into the enterprise networking market in direct competition with Cisco Systems Inc. (Nasdaq: CSCO), in a big way. There are several things Extreme has that Juniper might want, including Gigabit Ethernet technology, enterprise customers, and a wireless LAN switching product line.

Extreme had resurfaced as a hot acquisition prospect when Juniper's last shopping binge was just starting to get underway (see Juniper's Slow Shopping Trip and Valley Wonk: Juniper's Shopping List).

But all of this has been said before, without a deal panning out (see Juniper's Extreme Thoughts Are Back, Would Juniper Go to Extremes?, and Juniper To Buy Extreme? ).

One thing that might help grease the wheels? Extreme's stock is trading close to all-time lows, and its market capitalization is just $560 million, giving it a price-to-sales ratio of just 1.5.

Extreme and Juniper spokespeople had no comment on the rumors.

— R. Scott Raynovich, US Editor, Light Reading