Transparent Cisco IOS Firewall(ترجمه فارسی بزودی در همین وبلاگ)

Transparent Cisco IOS Firewall

Cisco IOS routers can be configured as a layer 2 bridges, this means that you can configure two or more interfaces to be in the same layer 2 domain and that traffic will be switched instead of routed. Another feature that has been added since IOS 12.3(7)T is the transparent Cisco IOS Firewall. This allows traffic filtering and stateful inspection using CBAC for the layer 2 bridge.

When you configure the router as a transparent firewall it will not do any routing and will only learn the MAC addresses on the interfaces and switch frames between the interfaces. The advantage of a transparent firewall is that you can place it at any location in your network without having to change any IP addresses or networking settings like default gateways.

To demonstrate this feature I will use the following topology:

 

پیکربندی Zone Base Firewall(ترجمه فارسی بزودی در همین وبلاگ)

Zone Based Firewall Configuration Example

Zone Based Firewall is the most advanced method of a stateful firewall that is available on Cisco IOS routers. The idea behind ZBF is that we don’t assign access-lists to interfaces but we will create different zones. Interfaces will be assigned to the different zones and security policies will be assigned to traffic between zones. To show you why ZBF is useful, let me show you a picture:

نشت کلمات عبور در پیِ وجود خطای امنیتی در چاپ‌گرهای HP

خطاهای امنیتی در برخی مدل‌های چاپ‌گر تک‌کاره لیرزی HP می‌تواند کلمه های عبور مدیریتی کاربران را برای مهاجمان راه دور آشکار سازد.