There's not much about firewalls etc. there IIRC, more about low level concepts like DNS, TCP and so on. Anyway it's a great book. You can also read online at h

There's not much about firewalls etc. there IIRC, more about low level concepts like DNS, TCP and so on. Anyway it's a great book. You can also read online at https://hpbn.co https://hpbn.co