Cisco Systems (NASDAQ:CSCO) is looking to Internet of Things services and technologies to spearhead its transition away from a hardware-dependent model, and the extent to which the transformation is successful should have a big impact on long-term performance.

The company's network switching business is its largest segment by revenue -- accounting for nearly 30% of sales last quarter, but demand for these devices is facing negative pressure as switching functions are virtualized and replicated through software. Cisco is also facing tough competition from rivals including Juniper Networks and Huawei in routing hardware, setting up limited growth.prospects in two of the company's most important segments and putting pressure on the company to deliver with its IoT-related endeavors.  

In order to make sure that Cisco gets a piece of what it believes could be a $19 trillion opportunity, the company has been buying up companies that can supplement its IoT strategy. Click through the presentation below to get caught up with Cisco's recent Internet of Things acquisition history.