Currently viewing the tag: "access-list"

Cisco: How to use reflexive access-list and why they are useful

By On March 30, 2009 · 4 Comments

Reflexive access-list are one of the method that help us achive firewall functionality with a router hardware. The other methods that serve to the same purpose are Context-Based Access Control (CBAC) and TCP Intercept. For an introduction to CBAC with example please check my older post Cisco: Use CBAC to achieve firewall functionality on router device . For TCP Intercept check my blog in the next weeks.

Today, I will present Reflexive access-list [...]

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Cisco: How to selective drop packets without using an access-list

By On March 5, 2009 · 2 Comments

The title actually was a request that I encounter during my CCIE RS preparation. Of course, that in the real world, I would go straight forward and implement an access-list do drop selected packets. But since the lab environment is different for the real one, you might get a task like the above one.

Let’s assume that we have a network topology with a central router (R1) that connects 2 routers (R2 and R3), like in a hub and spoke diagram. Communication between R2 and [...]

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