Anyone who has ever had a flat tire knows it’s always a good thing to have a spare. If your picnic gets rained out it’s always good to have a backup plan. The same philosophy applies to emergency notification. When a critical system such as paging, which is what we will focus on here, has a major component that fails it directly impacts the safety of everyone intended to be notified. You need a backup to ensure that any message still reaches the intended audience. There are certain levels of redundancy emergency notification systems can have depending on how robust.