Network security

Hi everyone,

I noticed a few people on here that seemed to have some real knowledge on here. I'm just a networking student and i was curious if anyone knows of some good network security or hacking sites. I know people normally don't want to give up their good info because it took them forever to find it but i thought i would ask. I'm not big on programming (I know basic dos codes and a little basic programming) but i would like to expand my knowledge in security so i will be able to better secure the networks i will be setting up, monitoring, and stuff. I know Cisco has some security measures in place and know about how to write the ACL's to restrict access and stuff but i was curious if anyone knows any sites on hacking networks so i can learn more about it. I know the only way to stop something is to know how it is being done. I know pretty much anything that is programed can be cracked but i figure the more i know and can learn about security the better network engineer i will become! I currently have access to aitp.org and cisco.netacad.net which have a lot of good info and have googled my way to many different sites but i'm always in search of more/better sites. I'm hoping some of you could point me to some good websites or forums where i can get useful information that will help me become more knowledgeable in internet/network security! Thank you to anyone willing to offer help to a college student in search of knowledge!! If do not want to publicly post certain websites or URL's feel free to pm me!!!