17 Oct

When your ISP sends you BPDU frames…

As an end-user, you should never receive STP BPDU frames from the ISP. The workstation in enterprise networks should not either. It is always a result of misconfiguration or lack of knowledge from network engineers about basics of network security. BPDU can reveal information about your network that can be later used to compromise it. In the worst case, an attacker can impact your system by changing the spanning-tree topology and perform a Man-In-The-Middle attack.

I noticed that my ISP is sending me BPDU frames. Let’s see, using this case real-life scenario, what we can tell about his network.

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01 Jun

How to manage simulation in VIRL from local network

Cisco and VIRL logos

I’ve been using Cisco VIRL for over two years for both learning technologies and testing new solutions as PoC. Accessing devices in simulation via embedded console link is easy but not efficient. I always wanted to manage simulation in VIRL from my laptop not desktop PC. Also in many scenarios you  may want to connect external servers like netflow collector or IPAM software you wanna test. Also it’s quite handy to have access to running simulation form Internet, isn’t it?

Let me show you how I connect Cisco VIRL running simulation to other devices in my network and to Internet. In this tutorial I assume that you didn’t change default VIRL networking configuration.

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