In the early days of networking, when computer networks were research artifacts rather than a critical infrastructure used by almost every second human on Earth, “network management” was practically unknown. Whenever one encountered a network problem, he might run a few pings to locate the source of the problem and then modify system settings, reboot hardware or software, or call a remote colleague to check console at the machine room.
An interesting discussion of the first major “crash” of the ARPAnet in 1980, long before network management tools were available, and the efforts taken to recover from and understand the crash can be read in RFC 789. The astonishment of the engineers taking part in post-mortem investigation could be read between the lines. As the public Internet and private intranets have grown from small networks into a large global infrastructure, the need to more systematically manage the huge number of hardware and software components within these networks has grown more important as well.
SNMP was quickly designed and deployed by a group of university network researchers and users at a time when the need for network management was becoming painfully clear.
- Research project, successor of SGMP
- SNMPv1 in 1988: initial revision
- SNMPv2 in 1993: improvements
- SNMPv3 in 1999: full redesign
- SNMPv3: backward compatible
- SNMPv3: full Internet standard (STD0062)
SNMP was initially thought as an interim solution to fill the need for network management tool while a more theoretically sound system was being developed by the ISO. Anticipating the transition to the new network management system, SNMP designers made SNMP modular. Although that transition never occurred, the modularity of SNMP help it evolving through three major versions and found widespread use and acceptance.
The IETF recognizes SNMP version 3 as defined by RFC 3411 .. RFC 3418 as the current standard version of SNMP. The IETF has designated SNMPv3 a full Internet standard, the highest maturity level for an RFC. In practice, SNMP implementations often support multiple versions: typically SNMPv1, SNMPv2c, and SNMPv3
Is it still relevant?¶
Considering how old SNMP is you might be wondering why it is still in use and is there a more modern alternative? Apparently, SNMP is still the primary way to do performance and fault management. SNMP is universally supported by all networking hardware manufactures and network management applications.
Perhaps one reason for SNMP being so tenacious is that, considering SNNP’s wide deployment, it takes too much effort to migrate to anything else. But the other reason is that no significant drawbacks have been found in SNMP at least in the areas of fault and performance management.
Additionally, SNMP is free and not controlled by any particular vendor. No copyright or licensing fees are required, so anyone can use it or build SNMP products on it.
Despite significant efforts made by technology companies and standards bodies over all these years, no other network monitoring standard was adopted so far. The most prominent open alternative is probably NETCONF (RFC 6241). However it mostly targets configuration management tasks rather than fault or performance monitoring. Additionally, NETCONF is significantly more resource intensive than SNMP is.
It is obviously possible to for everybody to come up with its own ad-hoc management system. That can be done very easily on top of HTTPS/JSON, for example. However that would only work with your application. Also, SSL engine might be heavier on resources.
Current and future uses¶
As for current SNMP deployment, its virtually impossible to estimate how many SNMP-enabled devices run on the modern Internet. One can possibly argue that SNMP monitors the all the Internet nowdays.
You may found SNMP useful for your home network monitoring or management needs. For instance you could easily setup an open source network monitoring application to watch, collect and graph bandwidth utilization at your Wi-Fi router for you home network (that helps spotting bottlenecks).
A significant innovation might be coming in the following years. And that is Internet of Things. All those small and low-power gadgets need to be monitored and managed. And that may bring new life to the SNMP technology. Almost three decades ago SNMP was designed for heavily resource-constrained computers of that time. Later on the computers grew in power and resources. But now we are back to building a massive amount of low-power computers for “things” and original SNMP lightweightness can serve us again!