In the networking arena, there have been many conflicting protocol suites. However, as of now, TCP / IP is the most used protocol stack in the world. This is because it was released at the right time under the right versioning and the protocol suite included many protocols to accommodate the needs of those days. The interesting feature about a protocol suite is that, you can actually add new protocols to this stack; which means the set of protocols been used will never get outdate unless a major change of the protocol suite happens. Both SNMP and SMTP are protocols used with TCP / IP protocol stack. In layman’s terms, this simply means that these two protocols deal with how two devices communicate with each other over a network like the internet.
Both of these protocols were introduced by the Internet Engineering Task Force (IETF) through RFC 1157 and RFC 821 respectively. RFC are actually a way of getting the inputs from the interested parties, and after they have been reviewed and refined by the experts, they get established as standards. SNMP and SMTP are two such standards.
SNMP
SNMP stands for Simple Network Management Protocol. As the name suggests, it manages various devices attached to a TCP / IP network. There are three tiers in this protocol. The SNMP Manager, SNMP Agent and the Managed Device. SNMP Manager is essentially a controller while SNMP Agent acts as an interface between the devices and the network. The Managed Device is the device that is controlled by the above two.
Communication process happens with a set of commands that are inherent to the protocol. These commands should be understood by the three tiers of the protocol in order for any communication to happen. For instance, using the GET command, the SNMP Manager can acquire information from a device. The Managed Devices may include PCs, Routers, Servers and Switches etc.
SMTP
SMTP stands for Simple Mail Transfer Protocol. It deals with the methods, to send and receive email from one client to another over the internet. It has a wide breadth that covers the mail servers and the applications that are used to send/receive emails. When you compose a mail and send it, the SMTP client communicates with the mail server and verifies the information about the email and the destination. Then the SMTP server sends your mail to the destination, and their SMTP client handles the receiving process in the same manner.
In essence, you can think of SNMP as a service that handles your inbound and outbound emails in a secure manner over the internet. Modern versions of the same protocol also defines the use of Mail Transfer Agents (MTAs), which act as a proxy between the sending and receiving email applications.
Conclusion
SNMP and SMTP are two standards that work together in harmony to achieve two different tasks. They work in such a way that one can control SMTP servers and MTAs through SNMP Managers. Further, SNMP Managers are capable of sending alerts through SMTP mail servers.