Cisco is on a buying spree this month. This morning it announced a $2.9 billion acquisition of mobile networking infrastructure provider Starent Networks, which follows on the heels of another $3 billion acquisition announcement two weeks go for Two weeks ago it announced the $3 billion acquisition of video video-conferencing company Tandberg.

You add $3 billion here and $3 billion there, and pretty soon you are talking about real money.

Cisco has always been a large acquirer, and the fact that it is opening its purse strings again is a good sign for tech M&A overall. But these are relatively large bets for Cisco, which needs to keep at the forefront of networking technologies. The Starent acquisition gives it a strong play in mobile data networks as carriers migrate to 3G and 4G platforms. Broadband is moving to mobile, and Cisco needs to be there.

If this acquisition helps it compete more effectively against the likes of Ericsson and Nokia Siemens, mobile data networks could become one of its fastest growing businesses.