1) What is SNMP?
In brief, SNMP, the Simple Network Management Protocol, is a protocol designed to give a user the capability to remotely manage a computer network by polling and setting terminal values and monitoring network events.
2) How does it work?
This was covered well in the previous document.
3) What does SNMP compose of?
3 elements: the MIB, the manager, and the agent. The MIB is covered in the network management
document, the other 2 are covered below.
4) What is the agent?
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.
5) What is the manager?
The manager is located on the host computer on the network. It's main role is to poll the agents for certain requested information. Again, there are lots of shareware managers available. For PC's my favorite is called NetGuard and is freely available. On UNIX network managers range from the simple and free to the very complex and expensive, like HP's OpenView.
6) How do I implement SNMP on my network?
This is the question being faced by many system administrators today. 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 (I find it easier).
7) What is the TCP/IP communication stack?
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.
8) How common is TCP/IP?
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.
9) Why would I want TCP/IP?
You would want TCP/IP if you wanted to create a WAN, connect to the internet, or send e-mail to a business contact. Think of it as a path to the outside world. Also (as mentioned above) you need to to implement SNMP.
10) Why would I want SNMP?
If you are using TCP/IP on a LAN, then SNMP should be fairly straightforward to implement (see above). Network management on a LAN is crucial as it ensures that the LAN is working as it is supposed to, and can also perform such duties as security checks and set terminal values.