Network Security

Question

I have been a .net developer for the past three yrs. Just curious to know about the network security field. What kind of work does the developers working in these area do? I really have not much idea about network security but what my understanding is these people are involved in securing network, preventing attacks on network as obvious. Could any one please give me some details about this field and also what does it take to move to this field.

Answer 1

Network security is a vast subject. On the developer side, I think you would most likely be concerning yourself with lots of encryption schemes and process security. There are basic things like using SSL for network traffic of a program to more advanced subjects like preventing any traces of a sensitive operation from remaining in RAM after a program has processed (and probably encrypted) it.

Answer 2

Take a look at "Security Engineering" by Ross Anderson. The first edition and part of the second are available for free online here. While he talks about many non-network issues, the principles mostly apply.

Answer 3

Today, you would need to become an expert in TCP/IP protocols. Everything from ARP, DNS, UDP, ICMG, BGP, and on and on. Most networks are IP-based, with IP-based firewalls. The firewalls will allow, for example, "TCP traffic on port 80" to come through. You need to be able to understand if that traffic is valid web surfing, DOS attack, or otherwise malicious. This can only be accomplished with detailed understanding of how IP networks work. Ditto for other protocols like DNS. In addition, lower-level understanding of ethernet communications and other means of transport (like cell phone networks or WiFi networks) would be important. I suppose it depending on what you mean by "network security" - to me this is below the application layer.