Welcome to the final installment of the Automated Network Scanning % team’s official blog. Our project is now over. The final tweaks are being made to our script, our scans are all shut down, and our team is beginning to finish their internship hours. A lot has happened since our last blog. We spent the majority of November running our scanner against different targets. The results we received from these scans were helpful in deciding what changes to make to our script. Despite our progress made on the scanner, there are a few things we could have done to make it better, if time permitted.
Testing Our ScannerTo test our scanner, our team used a combination of our VM, Pi, Pi network, and LCDI network. We began by targeting our Pi network that we made last month. First by running our scan on the VM. Then we believed that the superior power of the VM would make the scan run faster. Once we confirmed this, we would use our Pi scanner on the network. Our first scan was a smashing success. We used our VM to scan our pi network and it found all the servers we installed on the Pis. Now that we knew our script worked, we scaled up by testing our scan against the LCDI network.
The LCDI network scan performed without any errors. Our only issue was that it took too long. We made some improvements to the script that we believed would speed it up and then reran our test. This time the script worked much faster. This gave us much more confidence in our script, so we moved onto scanning off of our pi. As predicted, this scan was slower than the previous, but not beyond the realm of useable.
Error again
At this stage we decided to make another improvement to our scanner. We wanted to make our Pi run the script for the scan on boot. This meant that as the Pi was turning on ,it would automatically run our scanner. This process turned out to be more difficult than we thought, but eventually we got it working. In the meantime, we ran two more scans of the LCDI network that also worked. After these tests, the team felt comfortable to say our scanner worked without error.
Test resultsThe results that our scanner got were exactly what we were hoping to get. The first scan of the Pi network finished in 19.05 seconds. The scan found our ssh server, our http server, and both of the ports needed for our file server. We reran this scan to confirm our results and found that indeed our script worked. We then moved on to scanning the LCDI network. Our first scan of the LCDI network took 4 hours 25 minutes and 48 seconds. After adding our improvements, the scan only took 2 hours 28 minutes and 48 seconds. The three scans we did from the Pi averaged out to taking 3 hours 58 minutes and 48 seconds. This met our goal of being under four hours for a scan.
The picture above is a screenshot of the results from our third scan. The host IP’s and MAC addresses have been removed for security purposes. Using our scan results, we were able to identify multiple things about the LCDI network. The first thing we saw was the locations of both of the LCDI subnet’s. We also found a few IP’s that are up but not running any services.
What else could be done
The team is very happy with the work we have done here at the LCDI, but if we had some more time there are a few things that we would have improved. First, we would attempt to make the scanner faster. We met our goal of being under four hours, but we could still do better. We have some ideas of how to do this, like splitting the IP’s up into smaller groups and scanning these groups. Another improvement we would’ve liked to make was automatically identifying aspects of a targeted network. We could have coded in a function into our script that automatically identified subnets based off of our scan results. We also could have a function that identified IP’s that are up but not running any services, and give reasons as to why this is happening.
However, over all, our project was completed successfully.
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