Ok, some figures from the horse’s mouth (sorry David!):
“So when we say 4 copies it can be 2-6 and 16 off line. It’s just easier to say 4”
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and
…based on older kadmelia networks like guntilla/emule where 8/20
replicas was enough, but when all connections were very light, i…e not
checked for many hours/weeks/months between churn events. As we are
milliseconds between churn events then the chance of 4 nodes going down
in the average churn event seems unrealistic. This is good, but
potentially too good, we may not need 4 copies (kademlia republish is 24
hours, refresh == 60 mins). 4 copies may be way too much IMHO.
The bottom line for us. is that we lose no data, beyond that is just more caching really and not necessary.
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