A Watermark for
data synchronization
Data synchronization is the process of establishing consistency between source and target data stores, and the continuous harmonization of the data over time. It is fundamental to a wide variety of applications, including file synchronization and ...
describes an object of a predefined format which provides a point of reference value for two systems/datasets attempting to establish delta/incremental
synchronization; any object in the queried data source which was created, modified, or deleted after the watermark's value will be qualified as "above watermark" and should be returned to the client requesting data.
This approach allows the client to retrieve only the objects which have changed since the latest watermark, and also enables the client to resume its synchronization job from where it left off in the event of some pause or
downtime
The term downtime is used to refer to periods when a system is unavailable.
The unavailability is the proportion of a time-span that a system is unavailable or offline.
This is usually a result of the system failing to function because of an ...
.
Methodology
Watermark term is often used in Directory Synchronization software development projects. For example, products such as
Microsoft Exchange Server
Microsoft Exchange Server is a mail server and calendaring server developed by Microsoft. It runs exclusively on Windows Server operating systems.
The first version was called Exchange Server 4.0, to position it as the successor to the related ...
,
Active Directory
Active Directory (AD) is a directory service developed by Microsoft for Windows domain networks. It is included in most Windows Server operating systems as a set of processes and services. Initially, Active Directory was used only for centr ...
,
Active Directory Application Mode (ADAM), and
Microsoft Identity Integration Server 2003/ Microsoft
Identity Lifecycle Manager Server 2007, as well as
Cisco Unified Communications Manager
Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational digital communications technology conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, ...
or
Sun Microsystems
Sun Microsystems, Inc. (Sun for short) was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, ...
IPlanet and other
LDAP
The Lightweight Directory Access Protocol (LDAP ) is an open, vendor-neutral, industry standard application protocol for accessing and maintaining distributed directory information services over an Internet Protocol (IP) network. Directory serv ...
-based directory products are using DirSync and consequently will consume "watermark" object to provide efficient synchronization between directories. Watermark object sometimes can be referred as "cookie".
DirSync control implementation can differ from product to product, however concept of watermark will allow any product to read changes in the directory incrementally.
See also
*
Watermark (disambiguation)
*
Microsoft Active Directory
*
Microsoft Identity Integration Server
*
High-water mark (computer security) In the fields of physical security and information security, the high-water mark for access control was introduced by Clark Weissmann in 1969. It pre-dates the Bell–LaPadula security model, whose first volume appeared in 1972.
Under high-water ...
References
"LDAP Control for Directory Synchronization"Microsoft Corporation
{{Refend
External links
Understanding run profiles in MIIS 2003Microsoft Publishes Open Directory-Synchronization InterfaceLDAP Control for Directory
Data synchronization
Directory services