Basic Concepts

The following terms are used in the AllSync documentation and briefly explained here.

AllSync-Specific Terms

Actions
AllSync Scheduler
AllSync Service Tool
Error Report
Copy Mode
Copy Operation
Copy Preview
Process Copy Preview
Profiles
Profile Properties
Profile List
Source and Destination Folders
Report
Operation

Glossary

AllSync-Specific Terms

Actions
Actions are operations to be performed such as copying, deleting, or filtering files or folders. These actions are displayed in the tables of the report with corresponding symbols in front of a file or folder name.

AllSync Scheduler
The AllSync Scheduler automatically starts profiles at specific times or in response to certain events.

AllSync Service Tool
The AllSync Service Tool allows you to install the AllSync Scheduler as a Windows service.

Error Report
AllSync displays an error report if an internal program error occurs during use. In the error dialog, you can print, save, or email the error report. You can also continue using the application — however, this may lead to unexpected issues and further error messages. The error report is also saved in the general error log file error.txt.

Copy Mode
The copy mode defines the direction in which folders and files are copied between the source and destination folders, as well as the applicable copy rules.

Copy Operation
When you start a copy operation with a profile, files and folders in the source and destination folders are processed according to the defined copy rules.

Copy Preview
When you start a copy preview with a profile, all files and folders from the defined source and destination folders are read and displayed in the two tables of the report with the actions to be performed.

Process Copy Preview
Executes the actions for folders and files shown in the report.

Profiles
All settings for a copy operation are grouped into a profile.

Profile Properties
The profile properties contain all settings for a copy operation between source and destination folders.

Profile List
The profile list displays all available profiles.

Source and Destination Folders
Source and destination folders define between which folders a copy operation is performed.

Report
The report displays the actions to be performed for files and folders in two tables after a copy preview.

Operation
An operation can be a copy operation, the creation of a copy preview, or the processing of a copy preview.

General IT Terms

AES 256-Bit
AES 256-Bit is a modern and highly secure method for encrypting ZIP files. It is based on the Advanced Encryption Standard (AES) with a key length of 256 bits — a security level also used by banks and government agencies. This method reliably protects the contents of ZIP files from unauthorized access. To decrypt, the correct password is required. Without it, access to the files remains completely blocked.

BWT
BWT stands for Burrows-Wheeler Transformation — an advanced compression method that rearranges data before compressing it. This creates longer, uniform character sequences that are especially well suited for compression. The method is lossless and can achieve very high compression rates for certain file types, such as text files. However, BWT is not widely supported and is not compatible with all ZIP programs.

CRC32
CRC32 is a fast error detection method that calculates a 32-bit checksum from the file content. It is suitable for detecting random transmission errors but is not collision-proof and therefore not reliable for comparing file contents. This method is offered in AllSync only for backward compatibility.

Deflate
Deflate is the standard compression method in the ZIP format. It is lossless and combines two proven techniques to efficiently detect and store recurring data patterns. This makes it suitable for many file types and it is supported by all common ZIP programs.

Deflate64
Deflate64 is an extended version of the standard Deflate method for ZIP compression. It is also lossless but uses larger data blocks and extended bit patterns to compress very large files more efficiently. Compared to Deflate, Deflate64 can achieve higher compression rates for certain file types — but is not supported by all ZIP programs.

Drag & Drop
To perform this action: Click an object with the left mouse button, hold the button, drag the object to a new position, and release the button.

Hardlink
A hardlink is like a second, equivalent name for the same file on the disk (NTFS). When you create a file, the operating system assigns a storage location to its content. A hardlink creates a new directory entry that directly points to this identical storage location. This means: The file exists only once but has multiple names. It is only physically deleted when the last reference (the last hardlink) is removed.

Context Menu
A context menu offers context-specific actions for an object. It is opened by right-clicking the object.

LZMA
LZMA stands for Lempel-Ziv-Markov chain Algorithm and is a highly efficient compression method. It is lossless and often achieves significantly smaller file sizes than other ZIP methods — especially for large or highly redundant files. However, LZMA requires more processing power and time for compression and decompression. It is also not supported by all ZIP programs, which may limit compatibility.

MD5
MD5 stands for Message-Digest Algorithm 5 and generates a 128-bit checksum from any data. This allows files to be uniquely identified and compared — for example, to determine whether two files have the same content. The method is fast and widely used, but no longer considered secure due to the possibility of targeted manipulation. For comparing file contents — as in AllSync — MD5 is still practical and reliable as long as no security-critical requirements exist.

NTFS
NTFS is a modern file system from Microsoft used on Windows systems. It supports features such as access rights, file compression, encryption, large file sizes, and volume shadow copies. Compared to older file systems like FAT32, NTFS is more powerful and secure.

NTFS Junction Points
A junction point is a special folder that points to another folder located anywhere on the same disk (NTFS drive). When you or a program opens this folder, you are automatically and transparently redirected to the target folder.
The junction point acts as an internal folder-level redirect. It is not recognized as a simple shortcut but tricks the system into thinking the contents of the target folder are actually located at the junction point. This is often used by Windows itself to ensure compatibility with older programs.

SHA
SHA stands for Secure Hash Algorithm and refers to a family of cryptographic methods for calculating checksums from digital data. These checksums are used to uniquely identify and compare files — for example, to determine whether two files have the same content. AllSync supports the following variants: SHA-1 (160 bit) and SHA-2 with 256, 384, or 512 bit. The larger the checksum (e.g. 512 bit), the higher the likelihood that two different files will produce different checksums. At the same time, the larger the checksum, the greater the processing effort: SHA-2 (512 bit) is slower than SHA-2 (256 bit) but offers more security. SHA checksums are considered significantly more secure than CRC32 or MD5, especially the SHA-2 variants.

Volume Shadow Copy
Volume Shadow Copy is a Windows service that allows snapshots of files or entire drives to be created, enabling access to open or locked files for reading and copying. Files can be backed up without needing to close applications or interrupt processes. Supported on local NTFS drives. Local FAT32 drives are only supported if the system has at least one NTFS-formatted drive.

ZIP 2.0
ZIP 2.0 is the classic encryption method for ZIP files. It provides basic protection via password prompt but is technically outdated and easy to bypass. This method is no longer considered secure and should only be used when maximum compatibility with older programs is required.