Entity-Relationship Diagram (ERD)

This Cisco network diagram example was redesigned from the Wikimedia Commons file: EPN Frame-Relay and Dial-up Network.svg.
[commons.wikimedia.org/ wiki/ File:EPN_ Frame-Relay_ and_ Dial-up_ Network.svg]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. [creativecommons.org/ licenses/ by-sa/ 3.0/ deed.en]
This diagram depicts enterprise private network (EPN) using frame-relay and dial-up.
"An enterprise private network is a computer network built by a business to interconnect its various company sites (such as production sites, offices and shops) in order to share computer resources." [Enterprise private network. Wikipedia]
"Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network (PSTN) to establish a dialed connection to an Internet service provider (ISP) via telephone lines. The user's computer or router uses an attached modem to encode and decode Internet Protocol packets and control information into and from analogue audio frequency signals, respectively. Dial-up internet is sometimes used where Broadband internet access is not available; primarily in rural or remote areas." [Dial-up Internet access. Wikipedia]
The example "Enterprise private network" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Cisco Network Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.