What are the best practices for network security for an internal development environment. Besides adhering to updates, antivirus, and firewall.
For instance, is it recommended to use an IDS/IPS like Snort? Should you be whitelisting outgoing ports? Developers often needs access to a variety of resources, especially for testing purposes.
What kind of security controls are often overlooked in these type of environments?
I know this is a very broad question, so any and all answers are appreciated.
EDIT: The network is an internet connected LAN.