By David Russell, reporter at OptionMonsterNEW YORK -- Juniper Networks ( JNPR) has been bouncing and the bulls are looking for more mojo in coming weeks. OptionMonster's tracking systems detected the purchase of more than 4,000 December 17 calls, almost twice the previous open interest at the strike and therefore new positioning. Initial blocks priced for 53 cents, followed by more chunks that went for 64 cents. Calls lock in the price where investors can buy shares, so they can generate some nice leverage in the event of a rally. They can also predict moves in the share price because large traders often amass calls before building a position in a stock. That happened Tuesday as Juniper traded for about $16.90 when the calls hit. Buyers stepped in later in the session, driving shares up 1.67% to $17.09 even as the broader market fell in the afternoon. At the same time, the December 17 calls inflated by more than 10% to 70 cents. Overall option volume in the maker of telecom gear was quadruple its daily average. Calls accounted for more than 80% of the total, a reflection of the bullish sentiment. Russell has no positions in JNPR.