Metropolitan area networks (MAN). Computer and Network Examples

Metropolitan Area Network combines local networks located within a city, and is based on high data rate compounds, implemented on the basis of fiber channels and other digital data transmission channels. Now, with the increasing number of network communities, wireless local area networks based on 802.11b standard are combined into a wireless metropolitan area network consisting of affordable antenna systems and consumer-grade wireless equipment using 802.11a and 802.11b standards.

ERD Symbols and Meanings

Crow's foot notation is used in Barker's Notation, Structured Systems Analysis and Design Method (SSADM) and information engineering. Crow's foot diagrams represent entities as boxes, and relationships as lines between the boxes. Different shapes at the ends of these lines represent the cardinality of the relationship.
The Chen's ERD notation is still used and is considered to present a more detailed way of representing entities and relationships.
To create an ERD, software engineers mainly turn to dedicated drawing software, which contain the full notation resources for their specific database design - ERD symbols and meanings. CS Odessa has released an all-inclusive Entity-Relationship Diagram (ERD) solution for their powerful drawing program, ConceptDraw DIAGRAM.