Are you wondering what is the difference between one-way (mirrored) and two-way (bi-directional) storage platform synchronization? Learn about the benefits and challenges for both models as well as best practices for synchronizing your files across systems as we answer the following questions:
What is data synchronization? What is one-way data synchronization? What is bi-directional synchronization? What’s the difference between one-way and two-way data sync? How does data synchronization work? Why is it valuable? What are the benefits? What are the challenges? When is it useful? What are some use case examples? What common features exist in data synchronizers?
What is data synchronization?
According to dataintegration.info, the definition of data synchronization is “a process of establishing consistency among systems and subsequent continuous updates to maintain consistency.”
“The word ‘continuous’ should be stressed here as the data synchronization should not be considered as a one-time task or one-way operation. It is really a process which needs to be planned, owned, managed, scheduled and controlled.”
What is one-way data synchronization?
One-way sync (also known as mirroring) pushes files from your source platform to the destination system.
What is two-way data synchronization?
Two-way sync pushes and pulls files in both directions, from both systems.
What is the difference between one-way and two-way data sync?
Admins can choose between these file synchronization models based on their needs. One-way sync will sync any added or updated content in the destination, but two-way sync (also known as bi-directional syncing) will synchronize whether you update the file in the source or destination.

How data synchronization works and how to implement it
How you implement data synchronization depends on your needs, but there are several data synchronization techniques you can use, including using a hosted system, using a third party tool, and creating your own sync system.
Why is data synchronization important?
Working within multiple, dissimilar file systems can cause problems that data synchronization can solve.
Data sync challenges vs. advantages
In what scenarios is two-way synchronization helpful?
Two-way synchronization is particularly helpful in two scenarios:
- hybrid storage environments
- long-term migrations
Hybrid storage environments
The first, hybrid content management, is an increasingly popular storage option. This storage environment is popular with businesses who cannot migrate and/or consolidate files due to compliance or security mandates, or who have too many line-of-business systems to abandon on-premise storage. With both existing on-premises platforms and new cloud-based systems, bi-directional syncing keeps files on both platforms up-to-date.
Long-term migrations
Two-way synchronization is also useful in situations requiring long-term storage platform migrations. Businesses will often start with a two-way sync until they are ready to “unplug” their source system, allowing admins to continue working out of the old system while integrating the new system or training users. When admins are ready to make the switch, their user content will be waiting for them in the new system and they can pick up right where they left off, with no disruption to business operations.
Common features of file synchronization tools
Common features to look for in a file synchronization tool are:
- Synchronizes your data only when it needs synchronizing.
- Flexible filtering system to include only the files you want.
- Encryption for security, especially when synchronizing across the Internet.
- Compressing data sent across a network.
- Conflict detection where a file has been modified on both sources, as opposed to where it has only been modified on one. Undetected conflicts can lead to overwriting copies of the file with the most recent version, causing data loss. For conflict detection, the synchronization software needs to keep a database of the synchronized files. Distributed conflict detection can be achieved by version vectors.
- Open Files Support ensures data integrity when copying data or application files that are in-use or database files that are exclusively locked.
- Specific support for using an intermediate storage device, such as a removable flash disc, to synchronize two machines. Most synchronizing programs can be used in this way, but providing specific support for this can reduce the amount of data stored on a device.
- The ability to preview any changes before they are made.
- The ability to view differences in individual files.
- Backup between operating systems and transfer between network computers.
Final considerations
Users of bi-directional syncing should consider a robust platform synchronization tool to help administrators easily configure a sync between their existing systems.
Additional features to look for with two-way sync are filtering controls and file parallelism settings to help address common problems like slower throughput speeds. Your two-way sync tool should be able to perform in the largest environments and be capable of full bi-directional synchronization across a wide variety of platforms.