Recently, the Security Strategy from Cisco has become vague and ill defined.
Quick notes on the Virtual Context licensing requirements when using a Active/Standby (Failover) pair and looking for gotchas and traps.
One of the dangers of being from a pure cisco background is assumption. You treat all devices as if they have the same defaults as ‘normal’ Cisco devices. I think I’m pretty good at avoiding this, but it gets us all sometimes. As we all know, when you run long lived TCP connections through application […]
The thing about firewalls is that all networks have them. Once, firewall expertise was rare and a special job focus. Now, firewalls are like noses – everyone’s got one.
The Cisco Firewall Service Modules (FWSM) has a design limitation based on its ability to discriminate packet forwarding between multiple contexts. It also applies to ASA/PIX software. Lets review this in detail and learn the evil consequences.
In modern Enterprise networks, you typically have many clusters of firewalls protecting assets in your network. Since we use two or more layers of firewalls, we can put our DMZ for intermediate security zones in different places in our network. Lets gather together the different options and consider the merits or not, and sometimes how they ‘self-build’.
What IP addressing do you use for the sync / failover / HA links between your highly available devices ?
A TCP SYN Cookie is typically used in DDoS engines and load balancers to create another level of protocol security for Denial of Service attacks. Lets take a quick dive through the technology.
I read an article in the Financial Times Corroded to the core: How a staid Swiss bank let ambitions lead it into folly. It struck me how relevant this is to IT Security.
Sometimes, thinking too much stops you from checking the basics. I have often wished that the Cisco ASA supported more than one routing process like the Juniper Netscreen does (which does this brilliantly). Why didn’t I look for this sooner ?-
I have been working on a VPN setup that loads the Group Policy from a CiscoSecure ACS server. During the process I discovered the test aaa-server command. Its very handy tool when you are doing this kind of stuff.