"If your upstream has a 1000Mbps port, and sells 10 1000Mbps ports? that's the same 10x oversubscribe. But I /guarantee/ that you will hit contention at least once a week. Probably more often. If people expect 1000Mbps reliable off that, they will be very unhappy. "
I like that example.
Reminds me of account receivable and bad debt.
Better to have 1000 customers that owe you $30 each rather than 10 customers that owe you $3,000 each. I'm not factoring into this example the cost of billing or customer service. Strictly that if you have 1000 customers it's much less aggravating and you don't loose sleep at night worrying about a big customer that doesn't pay a bill.
Yup. And either way, you can solve the problem with capital. (Having a bunch of money laying around to cover the shortfall in the case of A/R, or having a very large burstable uplink with a small commit in the case of overselling bandwidth.)
Of course, burstable uplinks all suffer from the 'best effort' issue... if you go beyond your CIR, well, there's usually headroom, but not always.
I like that example.
Reminds me of account receivable and bad debt.
Better to have 1000 customers that owe you $30 each rather than 10 customers that owe you $3,000 each. I'm not factoring into this example the cost of billing or customer service. Strictly that if you have 1000 customers it's much less aggravating and you don't loose sleep at night worrying about a big customer that doesn't pay a bill.