Pros
There are many good reasons to work for Cisco Systems. In my opinion, the best reason to work for Cisco Systems is the technology you get to work with as an employee. The breadth and impact the technologies Cisco Systems has to offer to the communities and socienties Cisco serves is enormous. To have a direct hand in the hardware, software, and business processes that Cisco provides for its customers, knowing the impact you're having, is extremely satisfying. Other great reasons to work for Cisco is the location. Cisco's campus is right in the heart of Silicon Valley, where business and technology expands at the speed of human involvement and communication. To opportunities are great for those who are ready for them.
Cons
There are very few downsides of working at Cisco Systems. One particular downside is the very large scale of Cisco's business. Communication between different business units, and venturing through Cisco's intranet can sometimes be challenging. However, with increased knowledge of the different services available on the intranet, as well as constructing a vast network of colleges within Cisco will make navigating the intranet as well as navigating the Org charts much more manageable. One further downside to Cisco, particularly in San Jose, is the immense cost of living. Once you get over the initial price tag shock, you'll be just fine. Plus Cisco helps to compensate for the cost of living with your salary.