This blog is a technical background of the service - if you're looking to just get a proxy, head on over to https://instant-skype-proxy.com/ and follow the easy step by step instructions there!
Background
I'm sure everyone is aware of Dota matches being cancelled or postponed or teams receiving forfeit wins due to DDoS attacks. This occurs when someone is able to get the IP address of one of the players on a team and overwhelm their connection with a flood of traffic using a "booter" or "stress test" (read: paid DDoS) service.
The number one way to prevent this from happening is to avoid people finding your IP. If there's no target to attack, then the attacker can only try and hit the entire ISP, and taking down an internet service provider is of course a lot harder and much riskier than trying to attack a single user.
How Does Skype Fit Into This?
Skype is used by almost everyone in the esports scene, primarily as an instant messaging application. This is because of the widespread penetration of Skype - almost everyone has an account already, so it's the easiest thing to use.
Unfortunately due to Skype's design as a peer to peer application, once you sign into the Skype network, your IP address becomes associated with your Skype name. This is necessary so that when someone wants to contact you, they are able to reach the Skype program running on your PC.
This obviously has a lot of privacy and security risks - once your Skype name becomes known, anyone can find out your IP address. There are many websites called "skype resolvers" that will help people find an IP from a Skype name with no technical skill required.
Closing Skype also won't protect you - the directory servers maintain a list of recent IPs used by each name. The option inside Skype to only allow direct connections to your contacts is also ineffective as it does not prevent your IP from being exposed.
How To Fix It
You can hide your IP address when using Skype by routing the program through a 3rd party server. This way a skype resolver only shows the IP of the 3rd party server, not your IP. If the 3rd party server is attacked, the worst that can happen is your Skype will go offline.
There are several guides that let you configure Skype to use an open proxy, however open proxies are often very slow and unreliable as they are abused by spammers and such.
I created instant-skype-proxy to make it super easy to set yourself up with a private, non-shared proxy server that runs on professional hosting at DigitalOcean, a low cost VPS provider. After a few clicks, you'll be presented with a file that imports the proxy settings into Skype. After closing Skype, importing the proxy and changing your IP, your IP address will remain private and protected. DigitalOcean charges $5/month for their most basic server.
The proxy settings can be shared with teammates and friends, but be careful how many people use a single proxy as DigitalOcean does impose bandwidth limits. If the proxy experiences issues, everyone using it will lose connectivity to Skype.
Technical "How It Works"
I chose DigitalOcean as a server provider because they provide an extensive API (https://developers.digitalocean.com/v2/) with OAuth2 support. This lets me create an app at digitalocean to handle the setup.
Once the user approves the app, the service creates a Debian x64 Linux server ("droplet") at a chosen location, imports an SSH key and then uses SSH to perform various tasks such as configuring automatic security updates, removing unneeded services and security hardening. Finally, the service generates a random username and password, installs the 3proxy proxy server and configures it on a random port.
After the server is configured, a registry file is generated into a simple download that allows the user to import the proxy settings into Skype. For advanced users, a Windows Firewall script is also made that blocks Skype from accessing anything other than the proxy IP as an additional layer of security (note: this blocks the "Skype Home" feature).
A management page allows the user to reset the configuration should their login info become compromised in some way, as well as destroy the server should they wish to cancel the service.
Questions?
It's my hope that this makes it easy for teams and players to protect themselves so that tournament games are no longer disrupted due to attacks. If you have any questions or feedback about the service, please let me know!