Distributed Device Caching for Information Updating in Emergency Communications

On time information is the basis of coordination and decision making for emergency responses during or after disasters. However, accurate information about disaster scenarios, which usually comes from the monitoring devices or people in disaster areas, is often unavailable since the communication network is congested or even damaged. The information centric network (ICN) paradigm could be employed in this situation to help reduce the download traffic that needs to go through the bottlenecks. However, the regular ICN does not handle frequent information uploading, which posts a new challenge for integrating ICN into the emergency communication network. In this paper, we propose to use edge caches as the foundation of caching systems that support information updating. There are two major design work involved: the local cache placement and across access networks synchronization of the local writing caches in the disaster area. For cache synchronization, we present three different schemes and analyze their system capacity in supporting update traffic from the system's perspective and individual local cache's perspective. For local cache placemen, we propose schemes with flexible scale up and scale down abilities, and present performance analysis on each scheme.