UML communication diagram - Client server access

"The client–server model of computing is a distributed application structure that partitions tasks or workloads between the providers of a resource or service, called servers, and service requesters, called clients. Often clients and servers communicate over a computer network on separate hardware, but both client and server may reside in the same system. A server host runs one or more server programs which share their resources with clients. A client does not share any of its resources, but requests a server's content or service function. Clients therefore initiate communication sessions with servers which await incoming requests.
Examples of computer applications that use the client–server model are Email, network printing, and the World Wide Web." [Client–server model. Wikipedia]
The UML communication diagram example "Client server access" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Rapid UML solution from the Software Development area of ConceptDraw Solution Park.

The vector stencils library "Microsoft Exchange" contains 17 symbols of Microsoft Exchange elements for drawing the logical structure diagrams of Active Directory trees.
"Windows Messaging, initially called Microsoft Exchange, is an e-mail client that was included with Windows 95 (beginning with OSR2), 98 and Windows NT 4.0. ...
Microsoft Exchange gained wide usage with the release of Windows 95, as this was the only mail client that came bundled with it. In 1996, it was renamed to Windows Messaging, because of the upcoming release of Microsoft Exchange Server, and continued to be included throughout later releases of Windows up until the initial release of Windows 98, which by then included Outlook Express 4.0 as the default mail client.
The Windows Messaging email client had two branches of successors:
(1) In software bundled with Windows itself, these were Internet Mail and News in Windows 95 (and bundled with Internet Explorer 3), which was succeeded by Outlook Express 4.0 in Windows 98 (bundled with Internet Explorer 4.0 in Windows 95) and throughout newer Windows systems. These did not use the .pst file type.
(2) Microsoft Outlook became the professional-grade and more direct successor of MS Exchange Client, which still uses the .pst file type." [Windows Messaging. Wikipedia]
The symbols example "Microsoft Exchange - Vector stencils library" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Active Directory Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.
www.conceptdraw.com/ solution-park/ active-directory-diagrams