Explain why an analyst may use a black box symbol.
What will be an ideal response?
In data flow diagrams, a process symbol can be referred to as a black box, because the inputs, outputs, and general functions of the process are known, but the underlying details and logic of the process are hidden. By showing processes as black boxes, an analyst can create DFDs that show how the system functions but avoid unnecessary detail and clutter. When the analyst wishes to show additional levels of detail, he or she can zoom in on a process symbol and create a more in-depth DFD that shows the process’s internal workings—which might reveal even more processes, data flows, and data stores. In this manner, the information system can be modeled as a series of increasingly detailed pictures.
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Shadows, gradients, and 3-D effects are part of the ________ gallery
A) Shapes Quick Styles B) WordArt Text Effects C) SmartArt Quick Styles D) WordArt Quick Styles
Match each item with a statement below.
A. a protocol in IPv6 that permits nodes and routers on a local link to keep one another updated about any recent change in their network connectivity or status B. a method for checking the IPv6 address that a node wishes to use by sending a Neighbor Advertisement message to see if it is already in use by some other node C. messages used to find (or verify) the link-layer address for a local node, to see if that node is still available, or to check that an address is not in use by another node D. a message sent out by a router which contains its own link-layer address, the network prefix of the local subnet, the MTU for the local link, suggested hop limit values, and other parameters useful for nodes on the local link E. messages sent by nodes that include their IPv6 and link-layer addresses to maintain information about local addresses and on-link status F. a reserved address used as a source address if a node does not have an assigned IPv6 address G. a message sent out by a router to inform a sending node that there is a better first-hop router to access a destination node that is off-link H. a message sent out by a node to ask routers connected to a local link to identify themselves by immediately sending a Router Advertisement message rather than waiting for the next scheduled advertisement to appear I. a multicast address with link-local scope, which helps reduce the number of multicast groups to which nodes must subscribe in order to make themselves available for solicitation by other nodes on their local links