I just finished reading (most of) Inside Cisco IOS Software Architecture, published in 2000. Since I work with Cisco equipment that uses the traditional Cisco IOS, I figured it wouldn’t hurt to know a little more about it. What’s kind of funny, though, is that the book seemed to deal much more with Cisco hardware than the IOS software itself. The book mostly detailed how packets are processed and switched through the various hardware platforms that were available at the time the book was published, such as the Cisco AGS+, 2500-series, 7200, 7500 and the original 12000 series. The book also dipped into QoS a little bit at the end, which is software-based.
I can’t say that I learned a lot from this book; a good portion of it was either over my head or I just didn’t see how it would apply to anything I would ever be doing. However, as Cisco moves forward with new architectures and new IOS versions, such as IOS-XE, IOS-XR and NX-OS, this book does serve as a good reference of “how things used to be.” It was a short book so I don’t really feel like I wasted my time in reading it.