# System Requirements

## System Test

If you're experiencing any issue accessing the Cyber Skyline platform, please try the [System Test page](https://cyberskyline.com/support/system/test) available after sign in.

## Computer

Hardware & software requirements are fairly minimal. In general, we support the **latest** 3 versions of any major web browser such as Chrome (or any Chromium-based browser), Firefox, Safari, and Edge.

You can use **any modern operating system** that supports the above browsers, including Windows, macOS, ChromeOS (Chromebooks), or other Linux based operating systems with at least 1GB of RAM.

Minimum screen resolution is **1200x720**, but we highly recommend something with **1920x1080** screen resolution or larger.

## Network

Really any modern network will be acceptable at long as you have **3Mbps+ speed**, whether you have DSL, cable, fiber optics, or cellular (LTE/5G). 

The first page load will generally take a while on slower networks, but subsequent page loads will be able to leverage the browser cache.

Below are the domains that your organizational network should explicitly allow access to:

| **Required Domain** | **Use**                                                                       | **Notes**                                                                             |
| ------------------- | ----------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- |
| \*.cyberskyline.com | Cyber Skyline Platform / Scoring Engine                                       |                                                                                       |
| \*.cityinthe.cloud  | Designated Targets ([see 5.6](https://cyberskyline.com/terms)) for Challenges | Include all subdomains such as \*.web.cityinthe.cloud and \*.services.cityinthe.cloud |

{% hint style="info" %}
Some Internet Service Providers such as Comcast/Xfinity provides a home router for you and they may come with "Advanced Security" features that automatically blocks network traffic that they categorize as "attacking another network". 

You may need to temporarily disable these features on your router if you are performing an offensive attack against a Designated Target and then re-enable the features after you complete the challenge.
{% endhint %}