It is so important to distinguish between backup and archive as these core IT processes are not the same and are very often misunderstood. Understanding the difference between backup and archive can help you to reduce costs significantly and boost resource utilization.
In simple terms, a backup is designed as a short-term insurance policy to facilitate disaster recovery. A classic backup application takes images of active data periodically (daily, hourly, etc) in order to provide a method of recovering records which have been deleted or destroyed.
Backups are usually only retained for a short period - a few days or weeks - as more recent backup images replace previous versions. It is important to understand that emails can be deleted in between backups and would thus not be retained. Data is usually kept in a proprietary format which can cause problems for long-term retention. Backups only copy the data, leaving the original file in its place, over time increasing storage needs.
Email Archiving is designed to provide businesses with an ultra-secure repository for email records which need to be stored for a long period of time. This might be necessary in order to meet certain regulatory obligations or compliance. Email archiving provides businesses with a full record of communications, and additional security features like time-stamping and digital fingerprinting to ensure that the email has not been tampered with or edited - essential when providing emails as evidence in legal situations.
It is easier to find and retrieve records from an archiving solution compared to a backup. Emails may be requested by an external auditor or can be the result of an internal investigation. Archiving is also used to free up primary disk storage space from data that is no longer actively used but must be retained.
Archiving is the option if you need to collect mailbox data in the form of a cold copy. This is mainly used to fulfill legal obligations of keeping company data for several years. Backup on the other hand, is suited for operational purposes. It gives you a guarantee that when an unexpected data loss occurs, you are able to efficiently restore missing data and quickly get back on track. It's important to do both!