Critical networks e.g. telecare services, telemonitoring, are implemented to provide the information security and reliability that the end user desires, especially during an emergency. Unlike business carrier systems that are planned for the general public’s use, critical communication systems are designed particularly for public protection and other serious communication situations. Availability and reliability of such networks is highly desirable. The following thesis works to compare and analyze a variety of communication access technologies to find out the best primary means of data transportation for health critical services and model reliable communication link by using redundancy. This study also provides an efficient failover mechanism to implement redundant links. This strategy is intended to provide the reliable communication and to protect the established communication link.