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Simple Network Management Protocol

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  • GatewayA device that connects two or more networks with different types of protocolsIntelligent deviceConvert data according to the protocol
  • snmp

    1. 1. In the name of ALLAH, the most merciful and beneficent. 1
    2. 2. Group Members  Muhammad Imran Shareef ( GL )  Muhammad Hassan Rasheed  Hafiz Ali Raza  Abdul Munam  Awais Ghaffar  Muhammad Kamil 2
    3. 3. SNMP Simple Network Management Protocol 3
    4. 4. Simple Network Management Protocol ¤ SNMP is "Internet-standard protocol for managing devices on IP networks”. ¤ Devices that support SNMP include routers, switches, Servers, workstations, printers, modem racks, and more. ¤ SNMP is used to monitor network-attached devices. ¤ SNMP is a component of the Internet Protocol Suite as defined by the Internet Engineering Task Force (IETF). 4
    5. 5. SNMP concept 5
    6. 6. SNMP & Network Management History  1983 - TCP/IP replaces ARPANET at U.S. Dept. Of Defense, effective Birth of internet.  First model for net management – HEMS – High Level Entity Management system ( RFCs 1021,1022,1024,1076)  1987 – CMIP - Common Management information protocol , and CMOT ( CMIP over TCP) for the actual network protocol for use on the internet.  Nov 1987- SGMP – Simple Gateway Monitoring protocol ( RFC 1028)  Aug 1989 – Internet Standard Network Management Frame work ( RFCs 1065, 1066, 1067) 6
    7. 7. SNMP & Network Management History  Apr 1989 – SNMP promoted to recommended status as the de fecto TCP/IP network management frame work ( RFC 1098 )  June 1989 – IAB committee decides to let SNMP and CMOT develop separately  May 1990 – IAB promotes SNMP to a standard protocol with a recommended status ( RFC 1157 )  Mar 1991 – Format of MIBs and traps defined ( RFCs 1212, 1215)  TCP/IP MIB definition revised to create SNMP V1 ( RFC 1213 ) 7
    8. 8. Components of network management on the Internet 8
    9. 9. SNMP Framework Protocol: “Manager-Agent” interaction BER: Basic Encoding Rules MIB: Management Information Base (Database on managed devices)   SMI: Structure of Management Information (Rules of describing management information 9
    10. 10. SMI : Structure of Management Information  SMI defines the general rules for naming objects, defining object types and showing how to encode objects and values.  SMI does not define the number of objects an entity should manage or name the objects to be managed  define the association between the objects and their values. 10
    11. 11. SMI Data Types (Examples) • • • • • • • • • INTEGER -- signed 32-bit integer OCTET STRING OBJECT IDENTIFIER (OID) NULL -- not actually data type, but data value IpAddress -- OCTET STRING of size 4, in network byte order (B.E.) Counter -- unsigned 32-bit integer (rolls over) Gauge -- unsigned 32-bit integer (will top out and stay there) TimeTicks -- unsigned 32-bit integer (rolls over after 497 days) Opaque -- used to create new data types not in SNMPv1 • DateAndTime, DisplayString, MacAddress, PhysAddress, TimeInterval, TimeStamp, TruthValue, VariablePointer -- textual conventions used as types 11
    12. 12. MIB : Management Information Base  MIB creates a collection of named objects, their types, and their relationships to each other in an entity to be managed.  MIB is the definition of “objects” that should be provided on each managed node by the SNMP “agent”.  An “object” is a quantity or a field that describes one functional aspect of a device.  MIB objects are arranged in “groups”  Some groups relate to “layer” of the protocol stack.  Other groups relate to the system as a “whole” 12
    13. 13. MIB 13
    14. 14. BER – Basic Encoding Rules  The relationship between ASN.1 and BER  parallels that of source code and machine code.  CCITT X.209 specifies the Basic Encoding Rules  All SNMP messages are converted / serialized from ASN.1 notation into smaller, binary data (BER) 14
    15. 15. Features of SNMP ¤ Its design is simple , making it easier to implement on network of any size. ¤ Its simple design makes it easy for a user to program variables they would like to have monitored. ¤ It is popular and extensible.  A device manufacturer can easily add new registers for monitoring 15
    16. 16. Key Components of SNMP ¤ An SNMP-managed network consists of three key components.  Managed device  Agent — software which runs on managed devices  Network management system (NMS) — software which runs on the manager 16
    17. 17. Managed Device ¤ A managed device is a network node that implements an SNMP interface. ¤ It allows unidirectional (read-only) or bidirectional access to node-specific information. ¤ Managed devices exchange node-specific information with the NMSs. ¤ The managed devices can be routers, servers, switches, bridges, hubs, IP telephones, IP video cameras ,printers etc. 17
    18. 18. SNMP Agent ¤ An agent is a network-management software module that resides on a managed device. ¤ An agent has local knowledge of management information. 18
    19. 19. SNMP Components 19
    20. 20. Network Management System  A network management system (NMS) executes applications that monitor and control managed devices.  NMSs provide the bulk of the processing And memory resources required for network management.  One or more NMSs may exist on any managed network 20
    21. 21. NETWORK MANAGEMENT SYSTEM  We can say that the functions performed by a network management system can be divided into five broad categories:  Configuration management  Fault management  Performance management  Security management  Accounting management 21
    22. 22. Functions of a network management system 22
    23. 23. Basic Task of NMS  Configuration management  Keeping track of device settings and how they function  Fault management  Dealing with problems and emergencies in networks ( Router stops routing , Server loses power etc)  Performance Management  How smoothly is the network running?  Can it handle the work load it currently has? 23
    24. 24. 24
    25. 25. Proxy Agents ¤ Proxy Agents extend the capabilities of SNMP by allowing it:       Manage a device that cannot support an SNMP agent Manage a device that supports a non-SNMP management agent Allow a non-SNMP management system to access an SNMP agent Provide firewall-type security to other SNMP agents Translate between different formats of SNMP messages Consolidate multiple managed nodes into a single network address 25
    26. 26. SNMP Messages  Get-Request  Sent by manager requesting specific data from agent  Get-Next-Request  Sent by manager requesting data on the next MO to the one specified  Set-Request  Initializes or changes the value of network element  Get-Response  Agent responds with data for get and set requests from the manager  Trap  Alarm generated by an agent 26
    27. 27. 27
    28. 28. SNMP Operation  SNMP operates in the Application Layer of the OSI model.  The SNMP agent receives requests on UDP port 161.  The manager may send requests from any available source port to port 161 in the agent.  The agent response will be sent back to the source port on the manager.  The manager receives Traps and InformRequests on port 162.  The agent may generate notifications from any available port.  When used with Transport Layer Security or Datagram Transport Layer Security requests are received on port 10161 and traps are sent to port 10162.[3] 28
    29. 29. SNMP Versions ¤ Two major versions SNMPV1, SNMPV2 ¤SNMPV1 is the recommended standard ¤SNMPV2 has become split into:  SNMPV2U – SNMP with user based security  SNMPV2* - SNMP with user based security and additional features  SNMPV2C – SNMPV2 Without security 29
    30. 30. SNMP Versions  SNMPv1 specifies five core protocol data units (PDUs). Two other PDUs, GetBulkRequest and InformRequest were added in SNMPv2 and carried over to SNMPv3.  All SNMP PDUs are constructed as follows: Ip Header UDP Header Version Community PDUType Request id Error Status Error Index Variable bindings 30
    31. 31. SNMP V1  Version 1 :  SNMP version 1 is the initial implementation of the SNMP protocol.  SNMPv1 operates over protocols such as User Datagram Protocol (UDP), Internet Protocol  SNMPv1 is widely used and is the de facto network-management protocol in the Internet community  The first RFCs for SNMP, now known as SNMPv1, appeared in 1988:  Version 1 has been criticized for its poor security.  Authentication of clients is performed only by a "community string", in effect a type of password, which is transmitted in clear text.  '80s design of SNMP V1 was done by a group of collaborators who viewed the officially sponsored OSI/IETF/NSF (National Science Foundation) effort (HEMS/CMIS/CMIP) as both implementable in the computing platforms of the time as well as potentially unworkable. 31
    32. 32. SNMP V2  SNMPv2 (RFC 1441–RFC 1452), revises version 1  Improvements in the areas of performance, security, confidentiality, and manager-to-manager communications.  It introduced Get Bulk Request, an alternative of Get Nex Requests for retrieving large amounts of management data in a single request.  The new party-based security system in SNMPv2, viewed by many as overly complex, was not widely accepted. 32
    33. 33. SNMP V3  Version 3 :  Although SNMPv3 makes no changes to the protocol aside from the addition of cryptographic security  it looks much different due to new textual conventions, concepts, and terminology.  SNMPv3 primarily added security and remote configuration enhancements to SNMP.  Security has been the biggest weakness of SNMP since the beginning.  Authentication in SNMP Versions 1 and 2 amounts to nothing more than a password (community string) sent in clear text between a manager and agent.  Each SNMPv3 message contains security parameters which are encoded as an octet string.  The meaning of these security parameters depends on the security model being used.  In practice, SNMP implementations often support multiple versions: typically SNMPv1, SNMPv2c, and SNMPv3. 33
    34. 34. Advantages of using SNMP ¤ Standardized ¤ Universally supported ¤ Extendible ¤ Portable ¤ Allows distributed management access ¤ Light weighted protocol 34
    35. 35. Disadvantages of SNMP  Reducing network bandwidth  some large security gaps  largest security problems  privacy of data  authentication  access control  so simple that the information it deals with is neither detailed nor well-organized enough to deal with the expanding networks 35
    36. 36. SNMP Architecture and model Network management Organization Model Information Model Communication Model Functional Model 36
    37. 37. SNMP & The OSI Model 7 Application Layer Management and Agent APIs SNMP 6 Presentation Layer ASN.1 and BER 5 Session Layer RPC and NetBIOS 4 Transport Layer TCP and UDP 3 Network Layer IP and IPX 2 Data Link Layer Ethernet, Token Ring, FDDI 1 Physical Layer 37
    38. 38. Ports & UDP ¤ SNMP uses User Datagram protocol (UDP) as the transport mechanism for SNMP message Ethernet Frame IP packet UDP datagram SNMP Message ¤ Like FTP, SNMP uses two well-known ports to operate  UDP Port 161 – SNMP Message  UDP Port 162– SNMP Trap Message 38
    39. 39. Languages of SNMP ¤ Structure of Management Information ( SMI) Specifies the format used for defining managed objects that are accessed via the SNMP protocol ¤ Abstract Syntax Notation ( ASN .1) Used to define the format of SNMP message and managed objects( MIB modules ¤ Basic Encoding Rules ( BER ) Used to encode the SNMP message into format suitable for transmission across a network 39
    40. 40. THANK YOU 40