network protocols handbook.pdf

244Protocols GuideISO Protocols - Application LayerProtocol NameISO CMIP: Common ManagementInformation ProtocolProtocol DescriptionCommon Management Information Protocol (CMIP) is an ISOprotocol used with Common Management Information Services(CMIS), supports information exchange between network managementapplications and management agents. CMIS definesa system of network management information services. CMIPsupplies an interface that provides functions which maybe usedto support both ISO and user-defined management protocols.The CMIP specification for TCP/IP networks is called CMOT(CMIP Over TCP) and the version for IEEE 802 LAN’s is calledCMOL (CMIP Over LLC). CMIP/CMIS are proposed as competingprotocols to the Simple Network Management Protocol(SNMP) in the TCP/IP suite.CMIP uses an ISO reliable connection-oriented transport mechanismand has built in security that supports access control, authorizationand security logs. The management information isexchanged between the network management application andmanagement agents through managed objects. Managed objectsare a characteristic of a managed device that can be monitored,modified or controlled and can be used to perform tasks.CMIP does not specify the functionality of the network managementapplication, it only defines the information exchangemechanism of the managed objects and not how the informationis to be used or interpreted.The major advantages of CMIP over SNMP are:• CMIP variables not only relay information, but alsocan be used to perform tasks. This is impossible underSNMP.• CMIP is a safer system as it has built in security thatsupports authorization, access control, and securitylogs.• CMIP provides powerful capabilities that allow managementapplications to accomplish more with a single request.• CMIP provides better reporting of unusual network conditionsAccess to managed information in the managed objects is providedby the Common Management Information Service Element(CMISE) that uses CMIP (Common Management InformationProtocol) to issue requests for management services. Themanagement services provided by CMIP/CMISE can be organizedinto two distinct groups, management operation servicesinitiated by a manager to request that an agent provide certainservices or information, and notification services, used by themanagement agents to inform the managers that some eventsor set of events have occurred.Protocol StructureCMIP is an ASN.1 based protocol, whose PDUs (Protocol DataUnits) are based on ROSE. Each service element has its PDUswhich are part of the ROSE user data. The CMISE primitivesand CMIP operation are listed as follows:Correspondence between CMISE primitives and CMIPoperationsCMIS primitive Mode Linked-ID CMIP operationM CANCEL GETreq/indM CANCEL GETrsp/confM EVENT RE-PORT req/indM EVENT RE-PORT req/indM EVENT RE-PORT rsp/confM GET req/indConfirmedNot applicableNon-confirmedConfirmedNot applicableConfirmedNotapplicableNotapplicableNotapplicableNotapplicableNotapplicableNotapplicablem-Cancel-Get-Confirmedm-Cancel-Get-Confirmedm-EventReportm-EventReport-Confirmedm-EventReport-Confirmedm-GetM GET rsp/conf Not applicable Absent m-GetM GET rsp/conf Not applicable Present m-Linked-ReplyM SET req/indM SET req/indConfirmedNotapplicableNotapplicablem-Setm-Set-ConfirmedM SET rsp/conf Not applicable Absent m-Set-ConfirmedM SET rsp/conf Not applicable Present m-Linked-ReplyM ACTION req/indM ACTION req/indM ACTIONrsp/confM ACTIONrsp/confM CREATE req/indM CREATErsp/confM DELETE req/indM DELETErsp/confM DELETErsp/confConfirmedNot applicableNotapplicableNotapplicableAbsentm-ActionNon-confirmedNon-confirmedm-Action-confirmedm-Action-confirmedNot applicable Present m-Linked-ReplyConfirmedNot applicableConfirmedNotapplicableNotapplicableNotapplicablem-Createm-Createm-DeleteNot applicable Absent m-DeleteNot applicable Present m-Linked-ReplyRelated protocolsISO-SP, ISO-TP, ISO-IP, ISO-PP, ROSE, ACSE, SNMP