1 Operations Research in Green Internet Computing: state of the art and open challenges Guillem Cabrera*, Hebert Pérez-Rosés, Angel A. Juan, Joan M. Marquès IN3-Computer Science Department, Open University of Catalonia, Barcelona, Spain {gcabreraa, jmarquesp}uoc.edu, {ajuanp, hebert.perez}@gmail.com Abstract This paper discusses the opportunities that the emerging area of Green Internet Computing offers to the Operations Research community. With Internet services becoming more and more popular among users worldwide, there is a need to increase the number and size of datacenters offering these services. However, this also implies a sharp annual increase in energy consumption. Green Internet Computing aims at searching for energy-efficient solutions that can address environmental issues related to current and future cloud computing. Thus, one of the new goal for cloud computing is to drastically reduce its environmental effects without affecting too much the service performance and quality. Due to the large scale and geographical distribution of datacenter facilities, as well as to the complexity of the services being offered, the resulting multi-objective optimization problem arises as an attractive challenge for the Operational Research community. Keywords Internet computing, energy consumption, operations research, applied optimization, greenhouse gas emissions, simulation. 1 Introduction In the last decade, Internet services have become extremely popular for the majority of us. End- users quickly adapted themselves to social networks of different nature, such as Facebook, Twitter, LinkedIn, etc. Likewise, people are using many different services including, among others: web- based interactive email services, multi-purpose remote storage, user-owned on-line picture galleries, etc. Examples of these services are: Gmail, Hotmail, Dropbox, Google Drive, iCloud, or Flickr. What all these services have in common is that they are supported by large –and often geographically distributed– computing infrastructures managed by remote companies. They are offered to the user as simple web pages or wizard-installed applications, needing nothing else but an Internet connection and a low-end device such as a desktop computer, a notebook, or even a smartphone. All the resources supporting these services are commonly known as a cloud (Huber, 1999). Cloud computing has evolved as an easy way to outsource large computing infrastructures (Armbrust et al, 2010). As the service demand grows at nearly-exponential rates, so do the datacenters infrastructures necessary to support these services. These centers are often composed of a significant amount of relatively homogeneous servers disposed inside of secured and controlled atmosphere rooms. Network links managed by Internet Service Providers (ISP) connects them to the Internet and strict administration and maintenance policies guarantee the quality of the services provided to users.