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Network Management System. by Dedi Rahmawan Putra Advisor: Dr. Kai-Wei Ke. Outline. Network Management Simple Network Management Protocol (SNMP) Structure of Management Information (SMI) Management Information Bases (MIBs) SNMP Manager and Agent(s) Application on 802.16 device.
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Network Management System by Dedi Rahmawan Putra Advisor: Dr. Kai-Wei Ke Network Management and Its Application
Outline • Network Management • Simple Network Management Protocol (SNMP) • Structure of Management Information (SMI) • Management Information Bases (MIBs) • SNMP Manager and Agent(s) Application on 802.16 device Network Management and Its Application
Network Management Standard Network Management and Its Application
by IETF (for INTERNET) • Defining the standard (deciding on the content) • IESG: decides on formal status • Important area includes : Operations and Managements • Standard made by this group: Simple Network Management Protocol (SNMP) Network Management and Its Application
by ISO • important for the definition ofNetwork Management Standard • defined by: ISO-IEC/JTC1/WG4 • Part of OPEN SYSTEM INTERCONNECTION (OSI) • OSI has little practical function • Protocol defined for management: • CMIP: Common Management Information Protocol • CMIS: Common Management Information Service Network Management and Its Application
by ITU-T • defined by SG-IV • Standard for network made by this group: TMN: Telecommunication Management Network • Another groups within ITU-T also work on management Network Management and Its Application
Other Groups • DMTF (Distributed Management Task Force) • WBEM: Web Based Enterprise Management • CIM: Common Information Model • TM-Forum (Tele-Management Forum) • Originally based on OSI • OMG (Object Management Group) • looking at CORBA for management • IEEE Network Management and Its Application
Differences Network Management and Its Application
History • COPIED: • Manager-Agent concept • MIBS • ASN.1 • TERMINOLOGY starting as temporary solution many ideas were copied from OSI Management framework OSI introduced new ideas Real object orientation OSI Protocol Copied Network Management and Its Application
SNMP Simple Network Management Protocol Network Management and Its Application
SNMP Milestone SNMP Security SNMPv2 (parties) SNMPv2 (community) SMP SGMP SNMP SNMPv3 implementation experience draft full standard proposed standard draft standard draft standard proposed standard Network Management and Its Application
Standard • SMI (Structure of Management Information) Define how management information may look like • SMIv1: RFC 1155 • SMIv2: RFC2578 (currently used) • MIBs (Management Information Bases) Tell what management information exists • MIB-I: RFC1156 • MIB-II: RFC1213 • SNMP (Simple Network Management Protocol) Define how information is exchanged • SNMPv1: RFC1157 • SNMPv2: RFC1901, 1905, 1906 • SNMPv3: RFC2571-2575 Network Management and Its Application
Goals of SNMP • Ubiquity • Inclusion of SNMP functionality should be easy • Small code • Limited functionality • Management Extension should be easy • Management Information is modular • Adding new MIBs is easy • Management should be robust • Using connectionless transport Network Management and Its Application
Principle Operation Transport SNMP v1 : unreliable v2/v3: reliable alternatives Manager poll poll GET/SET poll TRAPS Agents variable MIB table Network Management and Its Application
SNMP Layering REAL VALUE Manager knows definition MIB Manager Agents SNMP PDUs Connectionless Transport Service Provider (UDP) Network Management and Its Application
SNMPv1 Command Network Management and Its Application
SNMPv2Command (mod. to v1) Network Management and Its Application
Remote Monitoring (RMON) • An extension of the network manager’s operation. • Monitor the data flowing on the remote network using probe or RMON agents. • RMON agents or probe has MIBs (v1:RFC1757; v2:RFC2021) • Overcomes degradation of lower operating rate WAN bandwidth when monitoring geographically separated networks. • Reduces the amount of information required to be transmitted to NMS. • Reduces the potential bandwidth saturation of the WAN circuit. Network Management and Its Application
RMON Principle Operation Network Management Station RMON Agent/Probe WAN circuit RMON-MIBs Agent MIB Network Management and Its Application
SMI and MIBs Structure of Management Information and Management Information Bases Network Management and Its Application
SMI • Denotes : • How MIB variables in an MIB are related to one another. • How variables are formatted. • Information to obtain the standardization of the MIB. • Additional RFC: • 1212: concise MIB definition (extends SMIv1) • 2578: textual convention (definition of new types) • Purpose: to make the definition of new MIBs easier • Help to guide MIB designer • Define the syntax • Allow tools to be built Network Management and Its Application
How Mngmt Information is Stored? • Management information within managed systems may be represented as: • SCALAR • eg. Current time, number of packet arrived • Type: integer, character, etc. • TABLES • eg. Two dimensional array of scalar. • Create a structure of scalars (size can be dynamic). Network Management and Its Application
How Mngmt Info. is Exchanged? • Can only exchange (a list of) scalars. • Cannot read/write a table with an operation. • To get a table one should reach each individual elements (quite complex). Network Management and Its Application
SMI vs. OSI • OSI management may have arbitrary structures. • OSI supports the retrieval a complete table in one command. • SMI is defined based on 1988 ASN.1 constructs inherited from OSI. • The SMI research group tried to get rid of ASN.1 • There’s no OSI standard for that version anymore, it has been removed from OSI • Building tools with ASN.1 is relatively difficult • SMIv2 improves SMIv1 Network Management and Its Application
SMIv2 Data Types of Scalars Network Management and Its Application
Example of Scalar Object TimeTicks OCTET STRING name IpAddress uptime address SNMP MANAGER AGENT Network Management and Its Application
Object Naming 1.2 1.1 1.2.1 1.2.2 Network Management and Its Application
Object and Instance • Object is the definition of something • Instance has value • In scalar, no distinction between object and instances • But in terms of table, object may have multiple instances, multiple rows • The case of table it’s useful to make distinction • To denote the instance, we need to add zero “0” after the ID of the object to get its value Network Management and Its Application
Get the value 1.1.0 1.2.1.0 1.2.2.0 Network Management and Its Application
Standard Naming Tree Network Management and Its Application
Object Type Definition Network Management and Its Application
e.g. Definition of Leaf Object -- Definition of address address OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-write STATUS current DESCRIPTION “Internet Address of this system” ::= {NEW-MIB1} Network Management and Its Application
e.g. Definition of Non-Leaf Object • Using OBJECT IDENTIFIER • Using OBJECT IDENTITY info OBJECT-IDENTIFIER ::= {NEW-MIB2} info OBJECT-IDENTITY STATUS current DESCRIPTION “The intermediate node” ::= {NEW-MIB2} Network Management and Its Application
Definition of A MIB NEW-MIB DEFINITIONS ::= BEGIN import statement(s) module identity definition definition of all node and leaf objects definition of implementation requirements END Network Management and Its Application
e.g. Module Identity Definition newMIBModule MODULE-IDENTITY LAST-UPDATED “200803111600Z” ORGANIZATION “NTUH” CONTACT-INFO ” National Taiwan University Hospital Taiwan DESCRIPTION “An Example of MIB Module” := {enterprises ntuh(20510)2} Network Management and Its Application
e.g. Import Statement Definition IMPORTS MODULE-IDENTITY, OBJECT-TYPE, TimeTicks, enterprises FROM SNMPv2-SMI; Network Management and Its Application
Retrieve Value from Table Entries Way 1(not being used by SNMP) 1.3.2.5 = 3 Way 2: X.C.I (used by SNMP) new-MIB.routeTable.next.8 = 3 destination Network Management and Its Application
Table Indexing • We also can use GetNext to retrieve table elements. • Index not need to be a consecutive number. • Not only Integer, any data type in SMI is allowed. • If index value is not unique: • add more index value which means we add another column to make it unique (multiple indexes). • The formula becomes X.C.I1.I2. Network Management and Its Application
Table Definition -- Definition of the route table routeTable OBJECT-TYPE SYNTAX SEQUENCE OF RouteEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION “This entity’s routing table” ::={NEW-MIB 3} routeEntry OBJECT-TYPE SYNTAX RouteEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION “A route to a particular destination” INDEX {dest} ::={routeTable 1} Network Management and Its Application
Table Definition (cont. 1) -- Definition of the new type for the row RouteEntry ::= SEQUENCE{ dest IpAddress, next IpAddress } Network Management and Its Application
Table Definition (cont. 2) dest OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION “The address of a particular destination” ::={route-entry 1} next OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-write STATUS current DESCRIPTION “The internet address of the next hop” ::={route-entry 2} Network Management and Its Application
Textual Convention • To refine semantics of existing types. • Example: RunState ::= TEXTUAL CONVENTION STATUS current DESCRIPTION “…” SYNTAX INTEGER { running (1) runable (2) waiting (3) exiting (4) } Network Management and Its Application
Notification Type • With SMIv2 and SNMPv2, there is a condition defined in MIB which if they happen, lead to a notification at the manager • Example: linkUp NOTIFICATION-TYPE OBJECTS {ifIndex} STATUS current DESCRIPTION “A linkUp trap signifies that the entity has detected that the ifOperStatus object has changed to Up” ::={snmpTraps 4} Network Management and Its Application
MIB-II Introduction Network Management and Its Application
MIB-II • Defines the variables to manage the TCP/IP Protocol Stack. • Doesn’t define the layer below IP, nor the application on the top of transport layer. • There are 170 variables being defined in MIB-II, mostly read-only. • Defined based on SMIv1. Network Management and Its Application
Design Criteria • Essential for Fault or Configuration Management • Only weak control objects • Small number of object are defined • Avoid Redundancy • Evidence on utility • Do not disturb normal operation • No implementation specific issues Network Management and Its Application
Structure Network Management and Its Application
MIB-II Groups in a Protocol Stack SYSTEM INTERFACES TRANSMISSION Network Management and Its Application
System Group Network Management and Its Application
sysServices physical layer (e.g. repeaters) data-link layer (e.g. bridges) internet layer (e.g. IP routers) end-to-end (e.g. IP hosts) application (e.g. nfs servers) Network Management and Its Application