An online backup is a backup done on an ongoing basis to a storage medium that is always connected to the source being backed up. The term “online” refers to the storage device or facility being always connected. Typically the storage medium or facility is located offsite and connected to the backup source by a network or Internet connection. It does not involve human intervention to plug in drives and storage media for backups to run.
Many commercial data centers now offer this as a subscription service to consumers. The storage data centers are located away from the source being backed up and the data is sent from the source to the storage center securely over the Internet.
Typically a client application is installed on the source computer being backed up. Users can define what folders and files they want to backup and at one times of the day they want the backups to run. The data may be compressed and encrypted before being sent over the Internet to the storage data center.
The storage facility is a commercial data center located away from the source computers being backed up. Typically they are built to certain fire and earthquake safety specifications. They have higher security standards with CCTV and round the clock monitoring. They typically have backup generators to deal with grid power outages and the facility is temperature controlled. Data is not just stored in one physical media but replicated across several devices. These facilities are usually serviced by multiple redundant Internet connection so there is no single point of failure to bring the service down.
Examples of Online Backups
There are many commercial service providers offering this as a subscription service. Some market it under the term Remote Backup or Cloud Backup
Advantages
- Offers the best protection against fires, theft and natural disasters.
- Because data is replicated across several storage media, the risk of data loss from hardware failure is very low.
- Because backups are frequent or continuous, data loss is very minimal compared to other backups that are run less frequently.
- Because it is online, it requires little human or manual interaction after it is setup.
Disadvantages
- Is a more expensive option then local backups.
- Initial or first backups can be a slow process spanning a few days or weeks depending on Internet connection speed and the amount of data backed up.
- Can be slow to restore.