Operating system support for massive replication
Arun Venkataramani, Ravi Kokku, Mike Dahlin · 2002
The increasing number of devices used by each user to access data and services and the increasing importance of the data and services available electronically both favor "access-anywhere" network-delivered services. Unfortunately, making such services highly available is difficult. For example, even though end servers or service hosting sites advertise an availability of "four nines" (99.99%) or "five nines" (99.999%), the end-to-end service availability (as perceived by clients) istypically limited to two nines because of poor wide area network availability [6]. Moreover, although network bandwidths are improving quickly, network latencies are much more difficult to improve in wide area networks, which limits performance for access-anywhere services if those services are delivered from a single location.