LongLivedPorts could enforce exclusive use of circuits
The discussion at http://archives.seul.org/or/dev/Jul-2010/msg00021.html deals with how best to solve the problem of keeping data from different applications on different circuits.
We could improve the situation pretty cheaply by allowing ports in the LongLivedPorts directive to get circuits for their own exclusive use. In other words, implement the original proposal at the above link (enforcing separate circuits per port) but apply it where it's needed most and least capable of causing lots of extra circuit-building.
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