Sorry for misattribution and confused date...
(silly me, i should be checking references before posting them
and not relying on memory alone).
...and on '67 vintage theoretical work by Kleinrock and Klein who showed
that routing can be done in scalable manner. Aggregation is nothing new.
Kleinrock and Kamoun.
Most of the basis for the above are available in:
Kleinrock, L. and F. Kamoun, "Hierarchical Routing for Large Networks,
Performance Evaluation and Optimization", Computer Networks, Vol. 1, No.
3, pp. 155-174, January 1977
(A copy of this paper that Dr. Kleinrock was kind enough to autograph for
me is one of my more prized possessions)
And another other classic:
Kamoun, F. and L. Kleinrock, "Stochastic Performance Evaluation of
Hierarchical Routing for Large Networks", Computer Networks, Vol. 3, pp.
337-353, November 1979.