A hacker news submission references the "The black triangle" blog note. I can only backup the author since I have experienced this many time.

For short, with some programs the visible part of it is merely just a black triangle while the invisible part may be complex or required a lot of efforts to achieve. The black triangle is then generally just a simple visual example to prove that the underlying system works.

That is the state of progress of DITP. I'm working to get the black triangle to become visible. In doing so I'm also writing the protocol specification so that the protocol may be reviewed and implemented by third parties in other languages or libraries.

The black triangle is like the first fruits of a fruiterer tree that may, sometime, took a long time to grow up to the point to be able to produce fruits.

"A note on distributed computing"

Jim Waldo, Geoff Wyant, Ann Wollrath, Sam Kendall. Nov 1994.

Abstract:

We argue that objects that interact in a distributed system need to be dealt with in ways that are intrinsically different from objects that interact in a single address space. These differences are required because distributed systems require that the programmer be aware of latency, have a different model of memory access, and take into account issues of concurrency and partial failure.

We look at a number of distributed systems that have attempted to paper over the distinction between local and remote objects, and show that such systems fail to support basic requirements of robustness and reliability. These failures have been masked in the past by the small size of the distributed systems that have been built. In the enterprise-wide distributed systems foreseen in the near future, however, such a masking will be impossible.

We conclude by discussing what is required of both systems-level and application-level programmers and designers if one is to take distribution seriously.