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.A MAN is a network with a maximumrange of about 75 kilometers (45 miles) orQuit the list when you re no longer interestedso, and with high-speed transmission capa-in the topic that binds the list members.Thisbilities.Most MANs include some type ofcuts down on the electronic junk mail traffictelecommunications components and activ-and also saves you the chore of wadingity to handle long-distance transmissions.through the messages.Because the distances are generally shortRefrain from repeating messages that haveenough to incur minimal telecommunica-already been distributed to the addresses ontions costs, the connections usually use verythe mailing list.high-speed lines, such as T3, at almost 45megabits per second (Mbps).MANs versus LANs and WANsMajor ResourceIn a NetWare 4.x environment, a category ofMANs have much in common with twodata used to guide backups.For example, aother network categories: local-area net-server or a volume might be categorized asworks (LANs) and wide-area networksa major resource.The data in a major(WANs).The following are the majorresource can be backed up as a single group.differences:Subdivisions within a major resource, suchMANs generally involve higher speedsas directories or subdirectories, are knownand greater distances than LANs.as minor resources.Unlike LANs, MANs generally includeprovisions for both voice and dataMalachitransmissions.A product that can be used to downloadMANs generally involve higher speedssoftware through your TV.Malachi consiststhan WANs.of an adapter for the PC, a cable to connectyour PC to the TV, and software to handlethe work.Malachi from En TechnologyMAN (Metropolitan-Area Network) 581MANs often include several LANs con- dual-ring topology and has opticalanected to each other via telephone lines.The fiber as the medium.figure  A MAN made up of several LANsbDQDB (Distributed Queue Dual Bus),connected by high-speed lines shows suchwhich is specified in IEEE 802.6.can arrangement.DQDB supports transmission speedsranging from 50 to 600 Mbps over dis- dMAN Architecturetances as large as 50 kilometers (30eMost MAN networks use either of twomiles).As the name implies, DQDBnetwork architectures:uses a two-bus topology.fFDDI (Fiber Distributed Data Inter-RELATED ARTICLESgface), which supports transmissionDQDB (Distributed Queue Dual Bus);speeds of 100-plus Mbps, uses ahFDDI (Fiber Distributed Data Interface)iA MAN MADE UP OF SEVERAL LANS CONNECTED BY HIGH-SPEED LINESjkLAN 1 LAN 2lmnopqrsLAN 3LAN 4tuThe LANs connected in such a network may be the same or different.vwBecause different types of LANs can be involved, connections tohigh-speed lines can take many forms.Bridges, routers, gateways, andxswitches are the most common connections.yz582 Managed ObjectSEE ALSO SEE ALSOLAN (Local-Area Network); WAN Network Management(Wide-Area Network)Manufacturing Message Service (MMS)Managed ObjectSEEIn a network management model, any ele-MMS (Manufacturing Message Service)ment in the network that can be managed(used or monitored).In addition to objectsMAP (Manufacturing Automationsuch as nodes, hubs, and so on, less tangibleProtocol)elements services and protocols, files andprograms, and even algorithms and connec- MAP is a specification for how to automatetasks in computer integrated manufacturingtions are also considered managed objects.(CIM) and other factory contexts.An earlySEE ALSOversion of MAP was formulated by GeneralNetwork ManagementMotors to guide its own procurement strate-gies.The most recent version, 3.0, differsconsiderably from the original specifica-Managing Processtions.By agreement, the MAP 3.0 specifica-In network management, the managing pro-tions were left unchanged for a six-yearcess is the software that is in charge of man-period, which ended in 1994.These specifi-agement chores.The managing processcations are expected to undergo numerousinitiates the requests for data and performsrevisions.any supported and requested analyses onthe data.MAP Network TypesThe managing process requests data andThree types of networks are distinguished inreports from managing agents.These agentsthe MAP model:are programs that monitor the activity ofnetwork stations with respect to whateverType 1: These networks connect main-attributes are of interest and report theframes, minicomputers, and PCsdata from this monitoring to the managingoperating at the highest levels in theprocess.automation hierarchy.The main tasksThe programs for each managing agentare information management, task(also known as a management agent) gener-scheduling, and resource allocation.ally run on the node the agent is monitoring [ Pobierz całość w formacie PDF ]