DDoS Prevention

We have noticed that there is a need for clarification regarding DDoS prevention. While it is the players’ responsibility to protect themselves from harmful network traffic, we want to help our community by providing some starting help towards a safe and fun experience!

What is a DDoS?

A Denial Of Service (DOS) or Distributed Denial Of Service (DDOS) is an overflow of network packets sent to an IP address, usually in order to cause harm. The majority of private connections will not be able to handle this network load and start to slow down or shut down entirely. While the DDoS is held up you will most likely not be able to establish a new connection as long as you are using the same IP address.

How do I know if I'm being attacked?

A DOS attack tends to start with minor latency increases which will then start to pile up until your network is unable to handle the load and can no longer access any outside information, not only StarCraft II. You will for instance no longer be able to open a website in your browser for as long as the attack is lasting. However, if you do not lose connection permanently, get small lag spikes instead of a gradual increase, or are disconnected from a game and are able to reconnect after a short period of time, you are probably not being targeted by a DDoS attack.

How am I making myself vulnerable?

In order to start a DDoS on your network, the attacker needs to acquire your IP address. While this is usually difficult, there are some ways you might expose your IP to strangers:
  • Skype: People on your contact list are able to uncover your IP. In addition Skype IP resolver can find out your IP without being on your contact list.
  • IRC: If you have an open IRC connection, it can be used to attack your network.
  • Suspicious links: You might connect to an attacker's server, exposing your IP.

How do I prevent DDoS attacks?

There are a number of precautions you can take in order to keep your IP secret:
  • Update Skype and any instant messengers you are using. Activate privacy settings.
    • To do this in Skype, select "Check for Updates" in the Help drop-down menu.
    • Privacy settings can be found in Tools -> Options -> Advanced -> Connection -> "Allow direct connections to your contacts only". This prevents people who are not on your friends list from finding out your IP. This will also stop Skype IP resolver from people who aren't on your contact list.

  • Proxy your Skype connection or even your whole network traffic.

  • Change your IP address.
    • Most providers will assign you a new IP every day. However many ISP's will also chagne your IP on request. If you need to change your IP quickly, contact your ISP's customer service.
    • Should your ISP not be able to help you, you can try to cycle your IP by physically disconnecting your network devices from the internet for a period of 24 hours.


After you protected yourself it is highly recommended that you get a new IP. Some Skype ID resolver will store IPs and even though you hid your IP they will still be able to access it, if you don't get a new IP adress. You can check your IP here.
Protecting your IP address is the player's responsibility. Acquiring a new IP address is a timely process and you will probably not be able to reconnect to a match. This guide will not establish a guaranteed protection and neither Blizzard nor ESL are not responsible for incomplete or ineffective protection.