Presentation on theme: "What are they and what do they (not) do?"— Presentation transcript:
1 What are they and what do they (not) do? FirewallsWhat are they and what do they (not) do?
2 Firewalls What is a firewall? A firewall is any mechanism that acts to restrict access to a network according to a set of defined rules.Function as “front doors” to a network.
3 Firewalls How do they work? By inspecting traffic that travels across/through them according to the policy that’s been set.
4 Firewalls How are they set up? Act as a go-between for any two given networksHave Rules been met?Yes? You can go.No, you can’t.The InternetFirewallYour Network
5 Firewalls Two main types Steps have been taken to create hybrids Routing based filtersFrom where did you come?Where are you going?Don’t care what you do once you get there.Content based filtersWhat are you trying to do?Not as common as Routing based because it’s harder to implement successfullySteps have been taken to create hybrids
6 Firewalls Two ways to approach the rule sets: Allow all except what is defined as unwantedPlace roadblocks/watch gates along a wide open road.Deny all except what is defined as wantedBuild a wall and carve paths for everyone you like.
7 FirewallsProblems:Firewalls as filters can be considered for most part to be infallible... but as a security measure? They can only enforce rules (generally static)The InternetFirewallYour Network
8 Your trusted friends who aren’t security aware Firewalls“Crunchy on the outside, but soft and chewy on the inside.”Step 1Your hackerStep 2The InternetYour firewallYour trusted friends who aren’t security awareYour network
9 Firewalls Conclusions People don’t just put up a thick front door for their sensitive belongings, you shouldn’t for your network either.Firewalls are an effective start to securing a network. Not a finish.Care must be taken to construct an appropriate set of rules that will enforce your policy.