She is also fun to read, being prepared to laugh at things that deserve it and to offer personal opinions, sometimes quite bluntly. I find BGP scary. It is configuration-intensive.
Routes can be permanently unstable.
It solves only whatever it happens to solve rather than providing a general-purpose solution. But we're stuck with it. Perlman roughly follows the protocol stack upwards. The bulk of Interconnections may be too detailed for most network administrators or programmers, but those without an interest in the theory may want to track down a copy just for the last two chapters. They share with you the warped way I look at the world, which is to notice and be distracted by suboptimal protocols in everyday life.