Fifteen years ago we published the first edition of The Internet Protocol Journal (IPJ). This seems like a good time to reflect on where the Internet is today and where it might be going in the future, instead of looking back at earlier developments the way we did in the tenth anniversary issue of IPJ.

In our first article, Geoff Huston discusses network service models, comparing the Internet to the traditional Public Switched Telephone Network (PSTN) in both technical and business terms, and asks if the fundamental architectural differences between these networks might explain the rather slow deployment of IPv6. Although the number of IPv6-connected users has doubled in the last year (see page 35), IPv6 still represents a small percentage of total Internet traffic.

The mobile device dominates today's Internet landscape. Smartphones and tablets are starting to replace more traditional computers for Internet access. Many technical developments have made this possible, including high-resolution screens; powerful processors; and compact, long-lasting batteries. Combine such developments with numerous radio-based technologies (GPS, cellular, Wi-Fi, and Bluetooth) and you end up with a handheld device that is always connected to the network and can perform almost any task, using an appropriate "app." Improvements to communications technologies such as the deployment of Long-Term Evolution (LTE) cellular data networks and Gigabit Wi-Fi (IEEE 802.11ac) are already underway.

We asked Vint Cerf, known to many as one of the "Fathers of the Internet," to look beyond what is possible with today's Internet and today's devices and predict what the future might look like in a world where every imaginable appliance is "smart," connected to the network, and location-aware. His article takes us through some history and current trends, and then describes how the future Internet might shape many aspects of society such as business, science, and education.

According to Wikipedia, a Data Center is "a facility used to house computer systems and associated components, such as telecommunications and storage systems." In our final article, Alvaro Retana and Russ White discuss how developments in link-state protocols, usually associated with wide-area networks, can be applied to data center networks.