The game I am currently working on is a mobile strategy game. We have a server cluster located in the US to serve players around the world. It should suffice the needs – players in Europe and Oceania will experience a latency around 50 to 200 ms, but there is rarely any packet loss, so it is totally playable. Unfortunately it is a whole different story for players in China.
And really it has nothing to do with the censorship. Basically, China has the most internet users, but its global bandwidth is so limited. At peak time, many users can’t even visit foreign sites, let alone playing games on foreign servers. Dedicated players find their own solutions by subscribing to VPN-like accelerators, or using the value-added services called NOS (previously known as Global Delicate Network, 国际精品网, offered by the largest ISP, China Telecom). Those solutions utilize reserved global bandwidth, for example the CN2 backbone, which is primarily used by transnational corporations. The thing is, you can not expect every potential user of yours to have such service. So what about that we find a server that uses such reserved global bandwidth, and make it a reversed proxy for our servers in the US?
Preparation and Client
The first thing is to enable alternative connections in client. We want to enable players in China to choose to connect to the reverse proxy while keeping users in the rest of the world unchanged. Our approach is that when a user opens the game, it retrieves all possible connections, including the server cluster itself and reverse proxies – we call them nodes. On the client side, it determines whether the player is in China, if so, it reveals the node options to the user. All data will then be sent to and receive from the chosen node.
Reverse Proxy Solutions
There are many reverse proxy solutions. I have listed a few:
| HTTP | TCP | UDP | |
| iptables | ✓ | ✓ | ✓ |
| NGINX | ✓ | ✓ | ✗ |
| Apache | ✓ | ✗ | ✗ |
| HAProxy | ✓ | ✓ | ✗ |
I will use HAProxy on Ubuntu 14.04 as an example:
Install HAProxy:
apt-get update apt-get install haproxy
Configure the reverse proxy. Add the following to the config file /etc/haproxy/haproxy.cfg:
listen gameproxy 0.0.0.0:1337 mode tcp option tcplog server gameserver 123.123.123.123:1337
Start HAProxy using the config:
haproxy -f /etc/haproxy/haproxy.cfg
Done. Now this node works as if it were the server itself.
Also, instead of implement a reverse proxy yourself, there are similar services you can purchase, such as VnetLink. It provides fast and cheap services. However its uptime isn’t as good, and its pricing model gives me big headache.