SNMP SIMULATOR Overview The SNMP Agent Simulator enables simulation of standalone SNMP agents to test and demonstrate SNMP-based management applications. Its unique ability to create default values from any SMIcompliant MIB or record variables from an existing agent and create variations on this basic simulation enables rapid simulation of SNMP devices. All SNMPv1, SNMPv2, and SNMPv3 operations (Get / GetNext / GetBulk / Set / Traps / Notifications) are supported. Description It is a very important protocol in the TCP/IP suite. A protocol, which is designed for external devices to interact with the management system is called SNMP. It allows monitoring and managing the network from a single workstation or workstations called SNMP managers (Management System). It was originally developed in the Internet community to monitor & troubleshoot devices like routers, bridges, etc. SNMP is actually a family of specifications that provide a means for collection of network management data from the devices residing in a network. Existing System For testing a Network Management topology, we need to simulate the network environment in our system. Different vendors are provided simulators for testing. The main disadvantage in this scenario is, the simulators are not open source and free. Buying a simulator for testing is not always economical. Appart from that, as it is not open, customisation also is not possible. Proposed System Here we are creating a simulator purely by JAVA. The advantages are: Free Customisable
MANAGEMENT SYSTEMS & AGENTS SNMP uses a distributed architecture consisting of management systems & agents. A management system is any computer running SNMP management software. The primary function of management system is requesting information from an agent. SNMP Agent is a process, running in all managed network devices. Its job is to constantly gather the information that the NMS may request and respond to requests from one or more NMSs with the appropriate data. SNMP manager requests data from the agent. The SNMP agent receives this request at port number 161 and it responds to the manager accordingly. Under erroneous conditions, the agent generates trap and notifies it to the NMS. NMS will receive this trap signal at port number 162. DataFlowDiagram. Communication between Manager and Agent using SNMP.
SNMP Community: A community is a group to which hosts running the SNMP services belong. Communities are identified by a community name for example "public". The use of a community name provides primitive security. An agent will not accept a request from a management system outside its configured community. An SNMP agent can be a member of multiple communities but the agents & managers should be the members of the same community to communicate with each other. The Simple Network Management Protocol uses a Management Information Base(MIB)/Agent paradigm. MIB/Agent paradigm. MANAGEMENT INFORMATION BASE (MIB) A MIB is a virtual database that identifies each manageable object by its name, syntax, accessibility, status, a text description and a unique Object Identification number (OID). The specifications of managed objects and grouping of, and relationship between, managed objects are addressed in MIB-II, which is specified in RFC 1213.
RFC (Requests For Comments) is a published series of documents of protocol standards for the Internet. These standards describe the internal working of the Internet. Most vendors' agents support MIB-II and their own proprietary (or Private Enterprise) MIB. MANAGEABLE OBJECTS DATABASE (MDB) The network management system uses the available Manageable Objects Database as a data dictionary of the questions it can ask the agent in each managed device. By compiling the various Private MIBs and MIB-II into the MDB, an NMS user can request and receive the information stored in the agent for each OID specified. OBJECT IDENTIFIERS (OID) Object identifiers represent each manageable object with a unique sequence of numbers and names. SNMP uses the number as an abbreviated form of the name to make requests or data values and to identify each response that carries the values. OID is a data pointing structure of ASN.1. OID uses dotted decimal format and uniquely identifies the objects. In that way, the Public MIB s manageable objects would all start with the names (ISO.Identified Org.DoD.Internet.Management.MIB) and the OID (1.3.6.1.2.1). A private MIB s manageable objects would all start with the names (ISO.Identified Org.DoD.Internet.Private.Enterprise.) and the OID (1.3.6.1.4.1). System Requirements System Requirements Hardware Requirements Windows CPU: 1.2 GHz Pentium Processor
Memory: 256 MB RAM Disk Space: Minimum 300 MB Java Version JRE 1.4.2 is bundled with the product for all operating systems Database Oracle Database is bundled with the product for all operating systems The SNMP Agent Simulator can simulate an SNMPv1, SNMPv2, SNMPv3 agent in two simple Modules: 1. SMI and MIB creation module: Description: Load any SMI-compliant MIB(s) in the SNMP Agent Simulator and create a basic simulation of the SNMP agent. SNMP Management Information Base A Management Information Base (MIB) is a collection of information that is organized hierarchically. MIBs are accessed using a networkmanagement protocol such as SNMP. They are comprised of managed objects and are identified by object identifiers. A managed object (sometimes called a MIB object, an object, or a MIB) is one of any number of specific characteristics of a managed device. Managed objects are comprised of one or more object instances, which are essentially variables.
Structure of Management Information The Structure of Management Information (SMI) defines the rules for describing management information, using Abstract Syntax Notation One (ASN.1). The SNMPv1 SMI is defined in RFC 1155. The SMI makes three key specifications: ASN.1 data types, SMI-specific data types, and SNMP MIB tables. 2. Configuration and Management Module: Description: Create variations on this basic simulation by recording real SNMP agents; configuring MIB values, SNMP traps and informs, simulating SNMP error conditions, and so on. SNMPv1 Protocol Operations SNMP is a simple request/response protocol. The network-management system issues a request, and managed devices return responses. This behavior is implemented by using one of four protocol operations: Get, GetNext, Set, and Trap. The Get operation is used by the NMS to retrieve the value of one or more object instances from an agent. If the agent responding to the Get operation cannot provide values for all the object instances in a list, it does not provide any values. The GetNext operation is used by the NMS to retrieve the value of the next object instance in a table or a list within an agent. The Set operation is used by the NMS to set the values of object instances within an agent. The Trap operation is used by agents to asynchronously inform the NMS of a significant event. Major features: Ease of use Record and replay SNMP devices. Values of SNMP agent MIB nodes can be recorded into XML file through GUI or command line interface. Recorded data file can be modified to simulate different configurations. Multiple agents in one JVM Complete SNMPv1, v2c and v3 (USM and VACM) support Support for dynamic row creation and deletion Support for BeanShell scripting language that is used in data file to model real time SNMP agent behavior Trap simulation
Error simulation Scalability. The number of agents on one computer is dependent on available system resources Community string indexing (multiple communities per IP address)