> From: Saint Wenhao

> Even if my Internet speed may be
> better than that, then still: it is limited by what my peers can provide.

This is a reasonable assumption, but it is not correct. P2P download speed 
is limited only by your bandwidth, not that of your peers. If you have 
extra capacity you add more peers. You drop the slower peers and connect to 
the faster peers - the ones offering capacity. You use standard deviation 
to detect which peers are slow. This will rapidly saturate your bandwidth, 
and is optimal for the P2P network. Your node may be pounding away at 
someone's laptop until timeout because the node software doesn't work this 
way. That's an implementation issue.

> And if I check 10 connected nodes, and all use NETWORK_LIMITED flag, so 
all
> are in   pruned mode, and all just act as proxies, fetching blocks from 
other full,
> archival nodes, then guess what: it is limited to the weakest link, the 
slowest
> node in the chain of connections.

This isn't how the protocol works. Addresses are advertised with their 
service bits. A node attempting to download blocks should not be connecting 
to a pruned peer. This is why this service bit exists. This is also why 
pruning is not good for the network. In 12 years of writing node software I 
have never seen peers produce a download limit. The chain can be 
consistently downloaded at the theoretical limit based on own bandwidth. We 
commonly operate from 1-2.5 Gbps and peers are never limiting.

> Also, I understand, why full, archival nodes, use rate limits: because
> otherwise, they would pay more bandwidth fees, if everyone would be able 
to
> get everything instantly, at full speed. Which is why when many people 
limit
> their connections, to not share too much data too fast, it is what it is. 
And it is
> normal, because nodes are not rewarded for their services, so they have no
> incentive to provide more, than the bare minimum they can handle.

Throttling is not a problem for the same reasons discussed above. Download 
time is local bandwidth limited, not peer limited. If you are downloading 
at a rate below your available bandwidth it is either because your hardware 
cannot keep up with your available bandwidth, or the software is not 
designed to.

Finally, I posted example bandwidths and related times over five and ten 
year periods to show the strongly declining relative trend despite strongly 
increasing data. There is no need anecdoting about bandwidth. It's easily 
obtained public information and a straightforward process to determine 
download time from these numbers.

https://en.wikipedia.org/wiki/List_of_countries_by_Internet_connection_speeds

> It shows around 1 MB/s in the "Network Traffic" tab from the GUI client. 

This is about 1/5 of an Eritrean mobile phone, the slowest mobile rate on 
Earth, or 1/4 of a Cuban land line, the slowest wire rate on Earth. Seems 
like there's more going on here than bandwidth, but it is not caused by 
peers.

Best,
Eric

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