Out of curiosity I checked 2010, Gilbert Held, A Practical Guide to Content Delivery Networks, 2nd ed., CRC Press. However it offers more of a historical overview: it presents general information on things like TCP/IP and the Cache-Control header, but also the Akamai High Definition network and how it uses Flash. Things get old so fast in this area. Probably also outdated, but interesting nonetheless, is 2015, Abhishek Verma et al., Large-scale cluster management at Google with Borg [2] (check chapter 7. Related work for more references). John Wilkes seems to be involved in multiple articles showing some of the Google internals such as 2020, Borg: the Next Generation [3].

[1] https://www.routledge.com/A-Practical-Guide-to-Content-Deliv...

[2] https://research.google/pubs/pub43438 https://www.youtube.com/watch?v=0W49z8hVn0k

[3] https://research.google/pubs/pub49065 https://research.google/people/JohnWilkes