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The agent runs off of each node on the network. Many UNIX SOFTWARE vendors include this with their TERMINAL software. It COLLECTS network and terminal information as specified in the MIB. Many public domain agaents are available (most notable the CMU agent). A common PROGRAMMING JOB is extending an agent to accomplish the specific needs of your network and this task is fairly straightforward given the right resources.

The agent runs off of each node on the network. Many UNIX software vendors include this with their terminal software. It collects network and terminal information as specified in the MIB. Many public domain agaents are available (most notable the CMU agent). A common programming job is extending an agent to accomplish the specific needs of your network and this task is fairly straightforward given the right resources.

A Management INFORMATION Base (MIB) is a COLLECTION of information that is organized hierarchically. MIBs are accessed using a network-management PROTOCOL such as SNMP. They are comprised of MANAGED objects and are identified by object identifiers.

A Management Information Base (MIB) is a collection of information that is organized hierarchically. MIBs are accessed using a network-management protocol such as SNMP. They are comprised of managed objects and are identified by object identifiers.

TCP/IP is very common. As EXPLAINED above, if you use "telnet" or "ftp" then you are using the TCP/IP COMMUNICATION STACK. It is so common, that MANY companies offer TCP/IP PC software for very low prices.

TCP/IP is very common. As explained above, if you use "telnet" or "ftp" then you are using the TCP/IP communication stack. It is so common, that many companies offer TCP/IP PC software for very low prices.

As STATED in the network management document, SNMP RUNS under the TCP/IP COMMUNICATION stack (it's a layer 7 application). The TCP/IP stack is a way in which vendor-inspecific computer networks can communicate. For instance, say my LAN of BRAND X's computers uses communication protocol XX to communicate. If I wanted to create a WAN with by connecting my LAN to a friend's LAN of brand Y computers (that use communication protocol YY to communicate; then I would have a problem... for how could protocol XX talk to protocol YY. This is where TCP/IP steps in, providing a common communication protocol between LAN's.

As stated in the network management document, SNMP runs under the TCP/IP communication stack (it's a layer 7 application). The TCP/IP stack is a way in which vendor-inspecific computer networks can communicate. For instance, say my LAN of brand X's computers uses communication protocol XX to communicate. If I wanted to create a WAN with by connecting my LAN to a friend's LAN of brand Y computers (that use communication protocol YY to communicate; then I would have a problem... for how could protocol XX talk to protocol YY. This is where TCP/IP steps in, providing a common communication protocol between LAN's.

 The first step is to implement the TCP/IP communication stack. This may appear on your network software (I know its on Windows NT) or you may have to purchase a TCP/IP stack implementation. Usually implementing TCP/IP involves giving each node on your network a DISTINCT IP address. "Telnet" is a key component of TCP/IP. If you can USE "telnet" on your network then you are running TCP/IP and you have nothing to worry about.
The next step is to get an SNMP manager and agent. Both of these are available freely THROUGHOUT the net. The agents should be installed on each node of the network while the manager should be installed on the MACHINES you wish to monitor the network from. Once all of these elements are in place you can follow the instructions provided with both your manager and agent and configure the network and SNMP accordingly. People who want to make SNMP easier to use may wish to either purchase or download a graphical network manager (such as IBM's Netview or HP's Open View Network Manager; there's also lots of good shareware network managers out. I HIGHLY recommend this route to SNMP newbie's .

 The first step is to implement the TCP/IP communication stack. This may appear on your network software (I know its on Windows NT) or you may have to purchase a TCP/IP stack implementation. Usually implementing TCP/IP involves giving each node on your network a distinct IP address. "Telnet" is a key component of TCP/IP. If you can use "telnet" on your network then you are running TCP/IP and you have nothing to worry about.
The next step is to get an SNMP manager and agent. Both of these are available freely throughout the net. The agents should be installed on each node of the network while the manager should be installed on the machines you wish to monitor the network from. Once all of these elements are in place you can follow the instructions provided with both your manager and agent and configure the network and SNMP accordingly. People who want to make SNMP easier to use may wish to either purchase or download a graphical network manager (such as IBM's Netview or HP's Open View Network Manager; there's also lots of good shareware network managers out. I highly recommend this route to SNMP newbie's .

Here are different VERSIONS of SNMP - SNMP V1, SNMP V2C, and SNMP V3.
SNMP version 1 - It is the oldest flavor. It is EASY to set up – only requires a plaintext community.
SNMP version 2c - It is identical to Version 1, except that it adds support for 64 bit counters.
SNMP version 3 - It adds security to the 64 bit counters. SNMP version 3 adds both Encryption and Authentication, which can be USED together or separately.

Here are different versions of SNMP - SNMP V1, SNMP V2c, and SNMP V3.
SNMP version 1 - It is the oldest flavor. It is Easy to set up – only requires a plaintext community.
SNMP version 2c - It is identical to Version 1, except that it adds support for 64 bit counters.
SNMP version 3 - It adds security to the 64 bit counters. SNMP version 3 adds both Encryption and Authentication, which can be used together or separately.

MIB is a hierarchical Database Structure for INFORMATION on the DEVICE. Example - Serial numbers are in a specific LOCATION, NIC Statistics etc.

MIB is a hierarchical Database Structure for information on the device. Example - Serial numbers are in a specific location, NIC Statistics etc.

SNMP uses the UDP port 161 for SENDING and receiving REQUESTS, and port 162 for receiving traps from managed devices.

SNMP uses the UDP port 161 for sending and receiving requests, and port 162 for receiving traps from managed devices.

A COMPLETE SNMP system consists of the FOLLOWING parts:-
SNMP Manager - A network MANAGEMENT system that uses SNMP to poll and receive data from any number of network devices. The SNMP manager usually is an application that runs in a central location.
SNMP Agent - A process that runs on the network DEVICE being monitored. All types of data are gathered by the device itself and stored in a local database. The agent can then respond to SNMP POLLS and queries with information from the database, and it can send unsolicited alerts or “traps” to an SNMP manager.

A complete SNMP system consists of the following parts:-
SNMP Manager - A network management system that uses SNMP to poll and receive data from any number of network devices. The SNMP manager usually is an application that runs in a central location.
SNMP Agent - A process that runs on the network device being monitored. All types of data are gathered by the device itself and stored in a local database. The agent can then respond to SNMP polls and queries with information from the database, and it can send unsolicited alerts or “traps” to an SNMP manager.

PROTOCOLS TCP/IP is used to CONFIGURE windows OPERATING System which is abrreviated as Transmission Control Protocol for transmitting DATA from one system to another.
Protocols IPX/SPX are used in UNIX operating system for transmitting data.
Protocols ICMP are used as Internet Protocols.

Protocols TCP/IP is used to configure windows Operating System which is abrreviated as Transmission Control Protocol for transmitting data from one system to another.
Protocols IPX/SPX are used in Unix operating system for transmitting data.
Protocols ICMP are used as Internet Protocols.

• LAN
• Wi-Fi
• WLAN
• WAN
• VAN
• PAN
• CAN

By using VLAN technology we can reduces the SIZE of BROADCAST DOMAIN.
VLAN (virtual local area NETWORK) is a logical grouping or SEGMENTING the devices under a single broadcast domain. as a result provides Security and Flexibility.

By using VLAN technology we can reduces the size of broadcast domain.
VLAN (virtual local area network) is a logical grouping or segmenting the devices under a single broadcast domain. as a result provides Security and Flexibility.

Defragmentation is smiple says bring the data at once PLACE in the DRIVE....when we copied or save a file it save on different sectors on the drive when U browse for the file it will search every sector id (for every sector we have an id).when defragmentation done all the data bring UPTO ONE part and it will take less time to reterive the data...

Defragmentation is smiple says bring the data at once place in the drive....when we copied or save a file it save on different sectors on the drive when u browse for the file it will search every sector id (for every sector we have an id).when defragmentation done all the data bring upto one part and it will take less time to reterive the data...

IIS used for Browsing Intranet
Net (all WEBSITES):through CCPROXY SOFTWARE
Or
Install WINDOWS 2003 server run DOMAIN controller promotions
--> Install DNS server default setting(not Manually)
In LAN system --> Local Area Connetion Status-->In properties--> Gateway is server IP address and DNS are ISP 
dNS(That system added to the windows 2003 server domain)
ccproxy software is easy

IIS used for Browsing Intranet
Net (all websites):through CCPROXY software
Or
Install windows 2003 server run Domain controller promotions
--> Install DNS server default setting(not Manually)
In LAN system --> Local Area Connetion Status-->In properties--> Gateway is server IP address and DNS are ISP 
dNS(That system added to the windows 2003 server domain)
ccproxy software is easy

An element management system (EMS) manages one or more of a specific type of NETWORK elements (NES). Using an EMS a user can manage all the features of each NE individually, but not the communication between NEs.Communication between NEs is managed by the network management system (NMS).A network management system is a combination of hardware and software used to monitor and administer a network.Network management refers to the maintenance and administration of large scale computer networks at the top level.
In brief,If network vendor wants to manage multiple EMS,vendor can go to NMS.If network vendor wants to manage multiple EMS,vendor can decide to go for NMS.If network vendor WANT to manage one or more of a specific type of network elements (NEs),vendor can decide to go for EMS.

An element management system (EMS) manages one or more of a specific type of network elements (NEs). Using an EMS a user can manage all the features of each NE individually, but not the communication between NEs.Communication between NEs is managed by the network management system (NMS).A network management system is a combination of hardware and software used to monitor and administer a network.Network management refers to the maintenance and administration of large scale computer networks at the top level.
In brief,If network vendor wants to manage multiple EMS,vendor can go to NMS.If network vendor wants to manage multiple EMS,vendor can decide to go for NMS.If network vendor want to manage one or more of a specific type of network elements (NEs),vendor can decide to go for EMS.

MANAGEMENT information is VIEWED as a COLLECTION of MANAGED OBJECTS information store in a Base is called MIB

Management information is viewed as a collection of managed objects information store in a Base is called MIB

It is connection between two or more COMPUTER or DEVICES through the transmission media for the purpose of COMMUNICATION and ACCESSING resources is called network and the whole process is called NETWORKING.

It is connection between two or more computer or devices through the transmission media for the purpose of communication and accessing resources is called network and the whole process is called networking.

Networking is defined as connectivity between peers inside network and outside network.Inside network connectivity in Networking topology is known as Lan and outside Network connectivity is called as WAN.Lan Is defined as Local Area Network between peer systems and Wan is defined as Wide Area Network between Lan to a Lan in different Location and this connectivity of lan in different locations is defined as WAN.Networking is depends on OSI layer which is defined as OPen System Internetworking.In OSI Layer data is reached to destination from source passing all the 7 LAYERS of OSI layer and these 7 layers were on EITHER side of network and they are defined as 

1. Presentation Layer
2. Data-link Layer
3. Network Layer
4. Transport Layer
5. SESSION Layer 
6. PHYSICAL Layer 
7. Application Layer

Networking is defined as connectivity between peers inside network and outside network.Inside network connectivity in Networking topology is known as Lan and outside Network connectivity is called as WAN.Lan Is defined as Local Area Network between peer systems and Wan is defined as Wide Area Network between Lan to a Lan in different Location and this connectivity of lan in different locations is defined as WAN.Networking is depends on OSI layer which is defined as OPen System Internetworking.In OSI Layer data is reached to destination from source passing all the 7 layers of OSI layer and these 7 layers were on either side of network and they are defined as 

its CACHE memory.

A CPU cache is a cache used by the central PROCESSING unit of a computer to reduce the average time to access memory.The cache is a smaller, faster memory which STORES copies of the data from the most frequently used main memory locations. As long as most memory accesses are to CACHED memory locations, the average latency of memory accesses will be closer to the cache latency than to the latency of main memory.
When the processor needs to read from or write to a location in main memory, it first checks whether a copy of that data is in the cache. If so, the processor immediately reads from or writes to the cache, which is much faster than reading from or writing to main memory.

its cache memory.

A CPU cache is a cache used by the central processing unit of a computer to reduce the average time to access memory.The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations. As long as most memory accesses are to cached memory locations, the average latency of memory accesses will be closer to the cache latency than to the latency of main memory.
When the processor needs to read from or write to a location in main memory, it first checks whether a copy of that data is in the cache. If so, the processor immediately reads from or writes to the cache, which is much faster than reading from or writing to main memory.

This the communication between computer systems or devices. A computer network is any set of computers or devices connected to each other with the ability to exchange data.
Data Communication is the process of transferring information from a sender to a receiver with the use of a medium in which the communicated information is understood by both sender and receiver. It is a process that ALLOWS organisms to exchange information by several methods. 
Telecommunications is a general term for a VAST array of TECHNOLOGIES that send information over distances. Mobile PHONES, land lines, satellite phones and voice over Internet protocol (VoIP) are all TELEPHONY technologies -- just one field of telecommunications. Radio, television and networks are a few more examples of telecommunication.

This the communication between computer systems or devices. A computer network is any set of computers or devices connected to each other with the ability to exchange data.
Data Communication is the process of transferring information from a sender to a receiver with the use of a medium in which the communicated information is understood by both sender and receiver. It is a process that allows organisms to exchange information by several methods. 
Telecommunications is a general term for a vast array of technologies that send information over distances. Mobile phones, land lines, satellite phones and voice over Internet protocol (VoIP) are all telephony technologies -- just one field of telecommunications. Radio, television and networks are a few more examples of telecommunication.

creating DAEMON is very simple in Linux. you just need to create a child process from its parent process and KILL the parent process. ALSO you should close all the I/O streams.[as daemon is a BACKGROUND process which is not interactive in nature].latter on you can write a init SCRIPT in /etc/init.d/ to make it a service.

creating daemon is very simple in Linux. you just need to create a child process from its parent process and kill the parent process. also you should close all the I/O streams.[as daemon is a background process which is not interactive in nature].latter on you can write a init script in /etc/init.d/ to make it a service.

Proxy can be defined as an intermediately device, which plays the role of an agent in the Context of SNMP.It works as a VIRTUAL LAN to the Devices Which are not having an Ethernet Inerface,Like MODEMS and Multiplexers.
By using the SNMPPROXY we can Know the STATUS of these(MODEMS ETC) devices.When an Agent performs PROXY role,it ACS on the behalf of one or more other nodes.A NETWORK MANAGER that wishes ti obtain the information from or control the node COMMUNICATES with the proxy agent.The proxy agent then translates the MANAGER's request to a form appropriate for the arget sysem and uses an appropriate nework management protocol to communicate with the target system.

Proxy can be defined as an intermediately device, which plays the role of an agent in the Context of SNMP.It works as a Virtual LAN to the Devices Which are not having an Ethernet Inerface,Like MODEMS and Multiplexers.
By using the SNMPPROXY we can Know the STATUS of these(MODEMS etc) devices.When an Agent performs PROXY role,it acs on the behalf of one or more other nodes.A NETWORK MANAGER that wishes ti obtain the information from or control the node communicates with the proxy agent.The proxy agent then translates the MANAGER's request to a form appropriate for the arget sysem and uses an appropriate nework management protocol to communicate with the target system.

SNMP AGENT is a management software which runs inside the managed device ie., NETWORK element.
The SNMP agent FETCHES the information from the managed device and RESPONDS back to the queries issued by the Network Management Softwares. It also involves in setting/updating the values in the managed device for any write operation commands issued by the Network Management Software.
SNMP Agent involves in sending the asynchronous Traps to the Network Management Software.

SNMP Agent is a management software which runs inside the managed device ie., Network element.
The SNMP agent fetches the information from the managed device and responds back to the queries issued by the Network Management Softwares. It also involves in setting/updating the values in the managed device for any write operation commands issued by the Network Management Software.
SNMP Agent involves in sending the asynchronous Traps to the Network Management Software.

Managed Device is a NETWORK element/device which has the SNMP Agent running in it.
The Managed device collects/fetches the MANAGEMENT information and MAKES this information AVAILABLE to the Network Management Software.

Managed Device is a Network element/device which has the SNMP Agent running in it.
The Managed device collects/fetches the management information and makes this information available to the Network Management Software.

MIB is the ACRONYM for Management INFORMATION Base.
MIB COMPRISES of set of managed objects which is ORGANIZED hierarchically. Each managed object is identified using an Object Identifier, termed as OID.
The managed object represents the characteristics of the managed device.

MIB is the acronym for Management Information Base.
MIB comprises of set of managed objects which is organized hierarchically. Each managed object is identified using an Object Identifier, termed as OID.
The managed object represents the characteristics of the managed device.

The BASIC commands in SNMP are,
1. GET
2. GET NEXT
3. GET BULK
4. SET
5. TRAP
6. INFORM

The basic commands in SNMP are,
1. GET
2. GET NEXT
3. GET BULK
4. SET
5. TRAP
6. INFORM

SNMP GET Request is a Read operation on the Managed Device.
The SNMP application (like Network Management Software) uses the SNMP GET request to retrieve the values from the Network ELEMENTS for a particular Object IDENTIFIER (OID). The SNMP Agent running in the Network element in TURN RETURNS the value corresponding to the Object Identifier.

SNMP GET Request is a Read operation on the Managed Device.
The SNMP application (like Network Management Software) uses the SNMP GET request to retrieve the values from the Network elements for a particular Object Identifier (OID). The SNMP Agent running in the Network element in turn returns the value corresponding to the Object Identifier.

The SNMP GET NEXT Request is same as Get Request operation. It is USED to RETRIEVE the value of the next OID value in the MIB hierarchy.
GET NEXT Request is useful to retrieve more than one piece of INFORMATION from the MANAGED Device.

The SNMP GET NEXT Request is same as Get Request operation. It is used to retrieve the value of the next OID value in the MIB hierarchy.
GET NEXT Request is useful to retrieve more than one piece of information from the Managed Device.

GET BULK REQUEST is used to retrieve large amount of DATA from the MIB objects.
It internally uses series of Get Next OPERATION to retrieve all data from the MIB TABLES.

GET BULK Request is used to retrieve large amount of data from the MIB objects.
It internally uses series of Get Next operation to retrieve all data from the MIB tables.

SET Request is a WRITE operation on the Managed DEVICE.
SET Request is used to set/write values in the Managed Device. BASICALLY it is used by the SNMP Manager APPLICATIONS to configure Network Elements with set of values.

SET Request is a Write operation on the Managed Device.
SET Request is used to set/write values in the Managed Device. Basically it is used by the SNMP Manager applications to configure Network Elements with set of values.

SNMP TRAP is a type of Asynchronous NOTIFICATION propagated from the Managed Device to the NETWORK Management System.
SNMP TRAPS are generated from the Network Elements when it experiences some error condition.

SNMP TRAP is a type of Asynchronous Notification propagated from the Managed Device to the Network Management System.
SNMP Traps are generated from the Network Elements when it experiences some error condition.

SNMP INFORM is similar to Traps but is more reliable.
When an AGENT sends a Trap to the Network Management System (Manager), the Manager RECEIVES the Trap and no acknowledgement is sent to Agent. By this way, the Agent doesn’t know WHETHER the Trap has been received by Manager or not. Whereas in Inform Request, the Manager UPON receiving the Inform Request can acknowledge the Agent with a SNMP Response PDU. By this way, Agent can be able to know whether Inform has reached or not.
If the Agent didn’t receive the Acknowledgement from the Manager, it can resend the Inform Request again.

SNMP INFORM is similar to Traps but is more reliable.
When an Agent sends a Trap to the Network Management System (Manager), the Manager receives the Trap and no acknowledgement is sent to Agent. By this way, the Agent doesn’t know whether the Trap has been received by Manager or not. Whereas in Inform Request, the Manager upon receiving the Inform Request can acknowledge the Agent with a SNMP Response PDU. By this way, Agent can be able to know whether Inform has reached or not.
If the Agent didn’t receive the Acknowledgement from the Manager, it can resend the Inform Request again.

• SNMPv2 is the evolution of SNMPv1 PROTOCOL.
• SNMPv2 support GET-BULK and INFORM OPERATION in addition to the operations SUPPORTED by SNMPv1.
• The message format of SNMPv2 GET, GETNEXT, SET are same as SNMPv1 but the message format of SNMPv2 TRAP is different from the SNMPv1 messag format.
• SNMPv2 also uses the Community based authentication which is same as SNMPv1.

Information MODULES are included in SNMPV2 and above. There are 3 types of SMI information modules, which are MIB modules, compliance statements, and CAPABILITY statements.
MIB modules contain definitions of interrelated managed objects. Compliance statements provide a systematic way to describe a group of managed objects that must be implemented for conformance to a standard. Capability statements are used to indicate the precise level of SUPPORT that an agent claims with RESPECT to a MIB group.

Information Modules are included in SNMPV2 and above. There are 3 types of SMI information modules, which are MIB modules, compliance statements, and capability statements.
MIB modules contain definitions of interrelated managed objects. Compliance statements provide a systematic way to describe a group of managed objects that must be implemented for conformance to a standard. Capability statements are used to indicate the precise level of support that an agent claims with respect to a MIB group.

There are TWO types of managed OBJECTS namely SCALAR and tabular.
Scalar objects define a single object instance.
Tabular objects define multiple related object INSTANCES that are grouped in MIB tables.

There are two types of managed objects namely scalar and tabular.
Scalar objects define a single object instance.
Tabular objects define multiple related object instances that are grouped in MIB tables.

SMI Stands for Structure of MANAGEMENT Information, which defines the RULES for describing management information, using Abstract SYNTAX NOTATION ONE (ASN.1).

SMI Stands for Structure of Management Information, which defines the rules for describing management information, using Abstract Syntax Notation One (ASN.1).

An object IDENTIFIER (or OID) uniquely IDENTIFIES a managed object in the MIB hierarchy. The MIB hierarchy can be represented as a tree with a nameless root, with various levels , which are ASSIGNED by different organizations.
The managed object getVersion can be uniquely identified either by the object NAME iso.org.dod.internet.private.enterprise.tdd.snmp.getVersion or by the EQUIVALENT object ID, .1.3.6.1.2.1.1.6

An object identifier (or OID) uniquely identifies a managed object in the MIB hierarchy. The MIB hierarchy can be represented as a tree with a nameless root, with various levels , which are assigned by different organizations.
The managed object getVersion can be uniquely identified either by the object name iso.org.dod.internet.private.enterprise.tdd.snmp.getVersion or by the equivalent object ID, .1.3.6.1.2.1.1.6