What‘s safe？ it means don‘t lose data. you can use cloud storage, saving your data on cloud service,all your terminal device can share your data with cloud storage. So，the cloud service always makes your data available.
What‘s the security？ it means data privacy and don‘t leak.Currently, most of the cloud storage just solves the safe，not security.For example,it‘s probably that you have some data which cannot be lost，but can be leaked，and also have some data which you would rather loss than leak, so you cannot storage it on cloud service. the example makes sense the differences between safe and security.
Although there are some encryption technology on cloud storage, but i prefer to storage my private data on my local，such as account ID and password.i think the data encryption is useless, because it can be cracked. the hard disk‘s life is not forever, so storage the data in local is probably to be lost.
How to resolve the probably? i think the best way is the family private cloud service solution. the device is a box, which composed by some hard disk to keep your data available, and you also can share，backup，syncronize your data using it without worrying about the internet safe, since it just your family local area network.
Safe And Security on cloud storage
原文：http://www.cnblogs.com/kellyxu/p/4620930.html