Network Security 101 By: David Crim

Security Balance between oposing interests Security v.s. Convienience Security v.s. Resources Security v.s. Risk

Security v.s. Convenience Long Passwords, or easy to remember Open access, or forced authentication http web-site, or https

Security v.s. Resources $$$ Configuration of devices Review of logs Follow through on problems Create and enforce policies

Security v.s. Risk Telnet v.s. SSH Credit Card company v.s. weblog Microsoft v.s. local shop

Security Scope You secure your house with alarm systems, a Doberman, barbed wire, electric fences,etc… Result: Your house is more secure For you! Police View The robbery is still going to happen This simply shifts the security risk around

Network Security Traffic Control Traffic Management Authentication Firewalls ACLs Traffic Management Packetshaper NetFlow Authentication Passwords / biometrics Policies

Traffic Control Firewall ACLs Cisco PIX IP Cop / Smoothwall Windows Firewall ACLs VLAN Subnet Intranet <-> Internet

Traffic Management Packetshaping NetFlows Packeteer Packetshaper Linux tools NetFlows Ntop Cisco NetFlow accounting

Authentication Passwords Complexity Expiration Rules Length Upper/Lower case Special characters Expiration Rules Password = lv89jdNm45 Rule – All numbers are proceeded by N+1 Written “hint” = lv8jdNm4 Rule 2 – All n’s are capitalized Written “hint” becomes lv8jdnm4

Policies Enforceable policies Unenforceable policies Passwords ACLs Proxy servers Unenforceable policies Network attachment EULA Plausible deniability 