In emergency management, network connectivity is key to communication, and many users expect connectivity during emergencies. Emergencies result in more people attempting to simultaneously communicate via cell phones, which places more stress on network bandwidth. In addition to placing phone calls, users may be transmitting text messages, emails, or photos.
Currently, 4G networks exist, with 5G being forecasted to be available around the year 2020. 5G systems would likely afford greater data transfer rates. In locations that do not have wireless networks, such as rural areas or places that service has been interrupted due to the emergency, wireless hubs that connect to satellites can be transported to various locations where connectivity is imperative. Cognitive radios will enable radios to find available channels in wireless spectrum and connect automatically (this process is also known as dynamic spectrum management). Radios can already support data transmission and this capability will expand to video transmission in the future. Additionally, power lines are capable of relatively high-speed digital data transmission, although frequencies may interfere with some radio signals.
Wireless sensor networks can be used to provide situational awareness. The sensors can be battery powered, allowing them to run during power outages. They provide continuous updates on physical or environmental conditions, which can then be screened for abnormalities. Filters can be applied to reduce noise in the data. This sensor data can be integrated with geospatial information.
Social networks are also an important factor in emergency response. Micro-blogging websites such as Twitter allow individuals to quickly broadcast information related to emergencies, which can be aggregated due to the use of keyword hash tags (e.g. #Seattle #flood). Twitter usage during emergency situations has been studied and proven to be useful, especially to gather a broad awareness from individuals as well as to disseminate real-time information to those affected by the situation. Posts to Twitter, called â€œtweets,â€ during an emergency situation come from individuals as well as services directly related to the emergency and the media. In fact, many people will sign up for Twitter accounts during emergency situations and then maintain their participation in the Twitter community. Much of the Twitter behavior is redistributing information through short tweets or links to articles to ensure that it reaches a broad audience, rather than original information. This process of reporting and relaying information is made possible due to the network systems discussed earlier. For social networks to be leveraged during emergency situations, the networks must maintain connectivity.