Topics in internet technology

he Internet Technology series is published in May and October every year. The issue deals with survey and tutorial articles on current research issues relating to Internet Technology. Over the years, there has been a steady and increasing number of submissions to this series, indicating a strong interest in its topics among our readers. This time, nine articles were submitted for possible publication in this issue. After a rigorous review process, we accepted only three articles for publication in this issue. The future Internet will consist of an interconnection of heterogeneous networks consisting of wireless, wired, and optical networks. Wireless Internet access is challenging in terms of minimizing requirements for battery power and bandwidth, and interworking with heterogeneous networks. Caching can improve access latency, reduce battery power consumption, and reduce bandwidth usage in the wireless Internet. Chen and Xiao provide a classification and detailed survey of cache access mechanisms and replacement algorithms. They suggest that wireless networks should be designed keeping in consideration the limitations posed by wireless networks/devices and the future heterogeneous wireless Internet. Heterogeneous networks also give rise to the problem of different networking protocols and packet formats. Tunneling, which consists of encapsulating a packet or frame within another packet of the same or a different network layer, is a commonly used technique to solve the issue of internetworking heterogeneous networks. Tunneling has also been used to provide end-to-end secure communications. The article by Saad, Alawieh, Gulder, and Mouftah discussed various tunneling techniques and looks at the interations between them to provide end-to-end connectivity. The article by McGregor Kaczmarek, Mosley, Dease, and Adams discusses the requirements of the next-generation Internet for national security and emergency preparedness. Such users must be assured of effective and priority service even under catastrophic conditions such as natural disasters and terrorist attacks, similar to what is now-a-days offered by telecommunication providers. The authors present test results of voice over IP for such priority users. The quality of this series depends on the quality of articles and the stringent refereeing carried out by a large number of volunteers. We would like to thank the authors and reviewers for their time and dedication to this series. We also invite potential authors to continue submitting high-quality articles. We would like to acknowledge the help of the Editor in Chief, Tom Chen, and Joe Milizzo and Sue Lange of the ComSoc publications staff for helping with the production of this series. We welcome any comments you may have to further improve the quality of this series.