From 2nd lead dev:
The capacity of the Blocknet's decentralised exchange increases with its user base. Since order broadcast and order matching are completely decentralised, there are no bottlenecks other than the ones which lie with users, namely their local internet connections.
In addition though, there is a shared capacity in the broadcasting system, which is really sky-high. Here is a relevant quotation from a Bitcoin wiki (
https://en.bitcoin.it/wiki/Scalability#Scalability_targets):
Network Let's assume an average rate of 2000tps, so just VISA. Transactions vary in size from about 0.2 kilobytes to over 1 kilobyte, but it's averaging half a kilobyte today. That means that you need to keep up with around 8 megabits/second of transaction data (2000tps * 512 bytes) / 1024 bytes in a kilobyte / 1024 kilobytes in a megabyte = 0.97 megabytes per second * 8 = 7.8 megabits/second. This sort of bandwidth is already common for even residential connections today, and is certainly at the low end of what colocation providers would expect to provide you with. When blocks are solved, the current protocol will send the transactions again, even if a peer has already seen it at broadcast time. Fixing this to make blocks just list of hashes would resolve the issue and make the bandwidth needed for block broadcast negligable. So whilst this optimization isn't fully implemented today, we do not consider block transmission bandwidth here.
Finally, there is an inherent limitation in the blockchains traders choose to use which affects the time between trading coins and re-trading them, which is the blockchain's confirmation time. Thus, if a trader wishes to trade Bitcoin at a "trustless" (well, widely regarded as non-risky) level of security, (s)he should wait an hour before re-trading an address. However, I have proposed a solution to this, in the form of a "0-conf slider" in the UI, which functions to filter orders according to the number of confirnations that the user is willing to wait for. Thus, at a small increase of risk, scalping and other fast trading strategies may be employed.
I think that suitably addresses concerns. The Blocknet is fast.