Block network connection for forge mods (and for plugins if you are using a hybrid bukkit server)
This mod can block connection to certain address, if you are having pain waiting for super long time when starting minecraft(waiting for a website to respond requests), it may help you.
It can also be used to monitor mod network connection attempts, which can help you find potencial attacking attempts/software vulnerabilities
Notice: SecurityManager will be removed in future Java releases, this mod will be broken at that time
Originally inspired by https://github.com/InfinityStudio/NonUpdate, for legacy Minecraft versions you can try this repo