Remote backup service

In the mid-1980s, the computer industry was in a great state of change with modems at speeds of 1200 to 2400 baud, making transfers of large amounts of data slow (1 MB in 72 minutes). While faster modems and more secure network protocols were in development, tape backup systems gained in popularity. During that same period the need for an affordable, reliable online backup system was becoming clear, especially for businesses with critical data.

More online/remote backup services came into existence during the heyday of the dot-com boom in the late 1990s. The initial years of these large industry service providers were about capturing market share and understanding the importance and the role that these online backup providers were playing in the web services arena. Today, most service providers of online backup services position their services using the SaaS (software as a service) and PaaS (Platform as a service) strategy and its relevance is predicted to increase exponentially in the years to come as personal and enterprise data storage needs rise. The last few years have also witnessed a healthy rise in the number of independent online backup providers.

Encryption

Data should be encrypted before it is sent across the internet, and it should be stored in its encrypted state. Encryption should be at least 256 bits, and the user should have the option of using his own encryption key, which should never be sent to the server.

Network backup

A backup service supporting network backup can back up multiple computers, servers or Network Attached Storage appliances on a local area network from a single computer or device.

Continuous backup – Continuous Data Protection

Allows the service to back up continuously or on a predefined schedule. Both methods have advantages and disadvantages. Most backup services are schedule-based and perform backups at a predetermined time. Some services provide continuous data backups which are used by large financial institutions and large online retailers. However, there is typically a trade-off with performance and system resources.

File-by-File Restore

The ability for users to restore files themselves, without the assistance of a Service Provider by allowing the user select files by name and/or folder. Some services allow users to select files by searching for filenames and folder names, by dates, by file type, by backup set, and by tags.

Online access to files

Some services allow you to access backed-up files via a normal web browser. Many services do not provide this type of functionality.

Data compression

Data will typically be compressed with a lossless compression algorithm to minimize the amount of bandwidth used.

Differential data compression

A way to further minimize network traffic is to transfer only the binary data that has changed from one day to the next, similar to the open source file transfer service Rsync. More advanced online backup services use this method rather than transfer entire files.

Bandwidth usage

User-selectable option to use more or less bandwidth; it may be possible to set this to change at various times of day.

Off-Line Backup

Off-Line Backup allows along with and as part of the online backup solution to cover daily backups in time when network connection is down. At this time the remote backup software must perform backup onto a local media device like a tape drive, a disk or another server. The minute network connection is restored remote backup software will update the remote datacenter with the changes coming out of the off-line backup media .

Synchronization

Many services support data synchronization allowing users to keep a consistent library of all their files across many computers. The technology can help productivity and increase access to data.

Bulk restore

A way to restore data from a portable storage device when a full restore over the Internet might take too long.

Centralized management console

Allows for an IT department or staff member to monitor and manage backups & restores for the regular user.

File retention policies

Many businesses require a flexible file retention policy that can be applied to an unlimited number of groups of files called "sets".

Fully managed services

Some services offer a higher level of support to businesses that might request immediate help, proactive monitoring, personal visits from their service provider, or telephone support.

Redundancy

Multiple copies of data backed up at different locations. This can be achieved by having two or more mirrored data centers, or by keeping a local copy of the latest version of backed up data on site with the business.

Regulatory compliance

Some businesses are required to comply with government regulations that govern privacy, disclosure, and legal discovery. A service provider that offers this type of service assists customers with proper compliance with and understanding of these laws.

Seed loading

Ability to send a first backup on a portable storage device rather than over the Internet when a user has large amounts of data that they need quickly backed up.

Server backup

Many businesses require backups of servers and the special applications or databases that run on them, such as groupware, SQL, ERP- or CRM-systems and directory services. This requires not only regular file-based approach, but specific point-in-time backups and restores for databases.[7]

Versioning

Keeps multiple past versions of files to allow for rollback to or restoration from a specific point in time.

Online backup services are usually priced as a function of the following things:

1. The total amount of data being backed up.
2. The total amount of data being restored.
3. The number of machines covered by the backup service.
4. The maximum number of versions of each file that are kept.
5. Data retention and archiving period options
6. Managed backups vs. Unmanaged backups
7. The level of service and features available

Some vendors limit the number of versions of a file that can be kept in the system. Some services omit this restriction and provide an unlimited number of versions. Add-on features (plug-ins), like the ability to back up currently open or locked files, are usually charged as an extra, but some services provide this built in.

Most remote backup services reduce the amount of data to be sent over the wire by only backing up changed files. This approach to backing up means that the customers total stored data is reduced. Reducing the amount of data sent and also stored can be further drastically reduced by only transmitting the changed data bits by binary or block level incremental backups. Solutions that transmit only these changed binary data bits do not waste bandwidth by transmitting the same file data over and over again if only small amounts change.

Remote backup has advantages over traditional backup methods:

• Remote backup does not require user intervention. The user does not have to change tapes, label CDs or perform other manual steps.
• Unlimited data retention (presuming the backup provider stays in business).
• Some remote backup services will work continuously, backing up files as they are changed.
• Most remote backup services will maintain a list of versions of your files.
• Most remote backup services will use a 128 – 2048 bit encryption to send data over unsecured links (e.g. internet).
• A few remote backup services can reduce backup by only transmitting changed data.
• Manage and secure digital data information.

Remote backup has some disadvantages over traditional backup methods:

• Depending on the available network bandwidth, the restoration of data can be slow. Because data is stored offsite, the data must be recovered either via the Internet or via a disk shipped from the online backup service provider.
• Some backup service providers have no guarantee that stored data will be kept private.
• It is possible that a remote backup service provider could go out of business or be purchased, which may affect the accessibility of one's data or the cost to continue using the service.
• If the encryption password is lost, data recovery will be impossible. However, with managed services this should not be a problem.
• Residential broadband services often have monthly limits that preclude large backups. They are also usually asymmetric; the user-to-network link regularly used to store backups is much slower than the network-to-user link used only when data is restored.
• In terms of price, when looking at the raw cost of hard disks, remote backups cost about 1-20 times per GB what a local backup would.[8]

Some services provide expert backup management services as part of the overall offering. These services typically include:

• Assistance configuring the initial backup
• Continuous monitoring of the backup processes on the client machines to ensure that backups actually happen
• Proactive alerting in the event that any backups fail
• Assistance in restoring and recovering data

There are three distinct types of backup modes: scheduled, manual and event-based.

• Scheduled Backup – data is backed up according to a fixed schedule.
• Manual Backup – backup of data is triggered by user input.
• Event-based Backup – backup of data is triggered by some computer events, e.g. database or application stoppage (cold backup).

• NIST definition of Cloud Computing