When I first saw these symbols, I thought that this was the name of an Indian leader: the letter Y reminded of the crown of feathers of the yellow-skinned leader from the books about the Wild West. And even pronouncing " YANG " aloud had such an effect that my far from nimble English bulldog Bucho jumped on four legs.
Of course, YANG is not a chieftain or an Indian or a bulldog. But let me use these characters to illustrate what YANG is without using computer terminology.
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, ? , Telnet, (network automation protocols), NETCONF RESTCONF.
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http://netconfcentral.org/modules/ietf-interfaces, YANG , IETF. IETF (Internet Engineering Task Force) - , ( !):
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(name)
(description)
(enabled)
It is better to talk about this in more detail in a separate article. It is now more important to understand that network devices store these data models in the same way. And when we request interface statistics using this standardized model, then the device knows for sure that it needs to use this particular model (ietf-interfaces @ 2018-02-20, for example, as in this case). If the network device supports YANG, then it knows exactly which way to go. The beauty of YANG is that it is a template language and not only organizes information for machines, but also makes it easier for humans to interpret.