The OID (Object IDentifier) relates a piece of information in the agent bound equipment with request for (GET) and configuration (SET) requirements of the human user.
Where as a human would quite happy to ask a piece of equipment "What is the drain current of transistor 3 of the third power amplifier in rack 2 of the transmitter Radio Beowolf?", the transmitter (at least those still without AI) would struggle to reply.
Whereas ask the transmitter "0x02 0x34 0x57 0x42 0x48 0x0D". It would reply "0x02 0x31 0x0D" without hesitation. This is a proprietry format only understood by the manufacture and client. So the OID comes into play, a universal means of identifying that current measurement on machine terms and obtaining a universally understood response Of cause the OID alone only refers to the equipment, there is still the need to identify the particular equipment, in this case Radio Beowolf, so that is the IP address.
Thus on one side we have the agent that translates the OID to manufacture/machine usable format. Then at the other end we have the NMS that translates the OID into a human compehensible format. (I am still waiting to be introduced to the first NMS with AI, we should have an interesting conversation!)
1.3.6.1.4.26637.127.127.2.34 is an OID (a rather short one). The ISO part (see RFC's and standards) 1.3.5.1.4 that states that the OID is for use by a private organisation. Within 1.x.x.x there are universal OID's (eg: sysup, systime...). Then comes the private entity identifier 26637 (OMB Sistemas Electrónicos S.A), get your own from IANA. Then the rest 127.127.2.34 is defined by the private entity.
When starting out the private part requires a good thoughtout to avoid future restrictions. It is almost impossible to change a MIB format after definition. Make it much much longer than initial estimate. Think that each equipment, variant, version will require a specific MIB tree. Consider that the individual equipments will be grouped and those groups assembled together.
An example; Starting with the MIB for a stereo generator. That stereo generator may have integtrated options an AES3/EBU card, a RDS generator. Each of these option need tyo lower down in the MIB tree than the stereo generator and also as independent MIBS. Then the stereo generator may be a pair in a 10Kw transmitter. Then transmiter, one of 5 in a base station within a N+1 system, ths MIB is getting taller. Then this base station may have a strategic reserve at a different physical location. So think big, think small and reserve a section for in-house inter-machine use.
With view to the client the OID tree will be supplied as a MIB file to be incorporated in a NMS browser. However for own application and agent translation use, the OID is used directly, embedded in the SO code.