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.
Cisco VIRL is powerful network simulation tool. There are weeks when I run simulations 24/7 because of some projects or learning are ongoing. With VIRL you get almost the latest firmware for supported platforms. Almost – sometimes you have to wait for next release for a new firmware to be available. I experienced it a few months ago when with ASA 9.7(1) release Cisco introduced the route-based VPNs (VTIs). At this point VIRL users got the 9.6(2) release bundled into latest simulator release. In other simulation, you may want to use different ASAv firmware versions for various nodes, so your simulation is more similar to your production network.
Cisco VIRL uses real firmware in the simulations. I will show you how you can add different ASAv firmware and use it in parallel with the software available on VIRL repository.
Now it is time to create Lambda functions for our small state machine. The first one will fetch version stored in S3 bucket object; the second function will get it from firewall using REST API. Then we will pass the collected values to the third function. With AWS Step Functions it is very easy to achieve!
This website stores some user agent data. These data are used to provide a more personalized experience and to track your whereabouts around our website in compliance with the European General Data Protection Regulation. If you decide to opt-out of any future tracking, a cookie will be set up in your browser to remember this choice for one year. I Agree, Deny