[nsp] 64 bit SNMP counters versus 32 bit SNMP counters

[Alex Rubenstein]

Simple.

100 mbit/sec = 100,000,000 bits/sec = 12,500,000 bytes/sec

2^32 bytes = 4,294,967,296

2^32 / 12,500,000 = 343 seconds = 5.72 minutes between counter flips

Or, at about 105 mbits/sec, you lose the ability to accurately calculate
usage in 5 minute samplings.


Or:

2^64 bytes = 18,446,744,073,709,551,616 (18 ?septillion?)

2^64 / 12,500,000 = 1,475,739,525,896 seconds = 46,763 years






On Tue, 1 Apr 2003, m.rapoport at completel.fr wrote:

> Hello all,
> There was a recent discussion about this topic on the list.
> Forgive me for this dumb question, but could someone briefly describe
> in practice the enhancement that a 64 bit counter provides on a 32 bit
> counter ?
>
> Regards,
>             Marc.
>
>
>
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