计算机网络——自顶向下方法与Internet特色(第三版)chapter9

Network Management9-1Network Management Network Management9-2Network Management9-3Network Management9-4Network Management9-5Network Management9-6Network Management9-7Network Management9-8Network Management9-9Network Management 9-10Network Management 9-11Chapter 9: Network ManagementChapter goals: rintroduction to network managementmmotivationmmajor componentsrInternet network management frameworkmMIB: management information basemSMI: data definition languagemSNMP: protocol for network managementmsecurity and administrationrpresentation services: ASN.1Network Management 9-12Chapter 9 outlinerWhat is network management?rInternet-standard management frameworkmStructure of Management Information: SMImManagement Information Base: MIBmSNMP Protocol Operations and Transport MappingsmSecurity and AdministrationrASN.1Network Management 9-13What is network management?rautonomous systems (aka “network”): 100s or 1000s of interacting hardware/software componentsrother complex systems requiring monitoring, control:mjet airplanemnuclear power plantmothers?“Network management includes the deployment, integration and coordination of the hardware, software, and human elements to monitor, test, poll, configure, analyze, evaluate, and control the network and element resources to meet the real-time, operational performance, and Quality of Service requirements at a reasonable cost.“ Network Management 9-14Infrastructure for network managementagent dataagent dataagent dataagent datamanaged devicemanaged devicemanaged devicemanaged devicemanaging entitydatanetwork management protocoldefinitions:managed devices contain managed objects whose data is gathered into a Management Information Base (MIB) managing entityNetwork Management 9-15Network Management standardsOSI CMIPrCommon Management Information Protocolrdesigned 1980s: the unifying net management standardrtoo slowly standardizedSNMP: Simple Network Management ProtocolrInternet roots (SGMP)rstarted simplerdeployed, adopted rapidlyrgrowth: size, complexityrcurrently: SNMP V3rde facto network management standardNetwork Management 9-16Chapter 9 outlinerWhat is network management?rInternet-standard management frameworkmStructure of Management Information: SMImManagement Information Base: MIBmSNMP Protocol Operations and Transport MappingsmSecurity and AdministrationrASN.1Network Management 9-17SNMP overview: 4 key partsrManagement information base (MIB):mdistributed information store of network management datarStructure of Management Information (SMI):mdata definition language for MIB objectsrSNMP protocolmconvey managermanaged object info, commandsrsecurity, administration capabilitiesmmajor addition in SNMPv3Network Management 9-18SMI: data definition language Purpose: syntax, semantics of management data well- defined, unambiguousrbase data types: mstraightforward, boringrOBJECT-TYPEmdata type, status, semantics of managed objectrMODULE-IDENTITYmgroups related objects into MIB moduleBasic Data TypesINTEGER Integer32 Unsigned32 OCTET STRING OBJECT IDENTIFIED IPaddress Counter32 Counter64 Guage32 Time Ticks OpaqueNetwork Management 9-19SNMP MIBOBJECT TYPE:OBJECT TYPE:OBJECT TYPE:objects specified via SMI OBJECT-TYPE constructMIB module specified via SMI MODULE-IDENTITY (100 standardized MIBs, more vendor-specific)MODULENetwork Management 9-20SMI: Object, module examplesOBJECT-TYPE: ipInDeliversMODULE-IDENTITY: ipMIBipInDelivers OBJECT TYPESYNTAX Counter32MAX-ACCESS read-onlySTATUS currentDESCRIPTION“The total number of input datagrams successfully delivered to IP user-protocols (including ICMP)” := ip 9ipMIB MODULE-IDENTITYLAST-UPDATED “941101000Z”ORGANZATION “IETF SNPv2Working Group”CONTACT-INFO“ Keith McCloghrie”DESCRIPTION“The MIB module for managing IPand ICMP implementations, butexcluding their management ofIP routes.”REVISION “019331000Z” := mib-2 48Network Management 9-21MIB example: UDP moduleObject ID Name Type Comments1.3.6.1.2.1.7.1 UDPInDatagrams Counter32 total # datagrams deliveredat this node1.3.6.1.2.1.7.2 UDPNoPorts Counter32 # underliverable datagramsno app at portl1.3.6.1.2.1.7.3 UDInErrors Counter32 # undeliverable datagramsall other reasons1.3.6.1.2.1.7.4 UDPOutDatagrams Counter32 # datagrams sent1.3.6.1.2.1.7.5 udpTable SEQUENCE one entry for each portin use by app, gives port #and IP addressNetwork Management 9-22SNMP Namingquestion: how to name every possible standard object (protocol, data, more) in every possible network standard?answer: ISO Object Identifier tree: mhierarchical naming of all objectsmeach branchpoint has name, number1.3.6.1.2.1.7.1ISO ISO-ident. Org. US DoD InternetudpInDatagrams UDP MIB2 managementNetwork Management 9-23Check out www.alvestrand.no/harald/objectid/top.htmlOSI ObjectIdentifier TreeNetwork Management 9-24SNMP protocolTwo ways to convey MIB info, commands:agent dataManaged devicemanaging entit