OpenView Network Node Manager: Designing and Implementing an Enterprise Solution

SNMPv2c and 64-bit Counters

The standard integer in SNMP MIB2 is 32 bits long. SNMPv2C MIB defines a new type of integer with the attribute name unsigned64 that is 64 bits long. Its maximum value is:

18,446,744,073,709,551,615

The reason for specifying such a large counter is found in rfc2233:

“As the speed of network media increase, the minimum time 
in which a 32 bit counter will wrap decreases. For 
example, a 10Mbs stream of back-to-back, full-size 
packets causes ifInOctets to wrap in just over 57 
minutes; at 100Mbs, the minimum wrap time is 5.7 
minutes, and at 1Gbs, the minimum is 34 seconds. 
Requiring that interfaces be polled frequently enough 
not to miss a counter wrap is increasingly problematic.”

Note that NNM handles a single counter ...