Lag

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In online gaming, lag is a noticeable delay between the action of players and the reaction of the server. Although lag may be caused by high latency, it may also occur due to insufficient processing power in the client and/or server.

The tolerance for lag depends heavily on the type of game. For instance, a strategy game or a turn-based game with a low pace may have a high threshold or even be mostly unaffected by high delays, whereas a twitch gameplay game such as a first-person shooter with a considerably higher pace may require significantly lower delay to be able to provide satisfying gameplay. But, the specific characteristic of the game matter. For example, fast chess is a turn-based game that is fast action and may not tolerate high lag. And, some twitch games can be designed such that only events that impact the outcome of the game introduce lag, allowing for fast local response most of the time.

Causes

Perhaps the most common type of lag is caused by network performance problems. Packet loss, corruption or jitter may all cause problems, but these problems are relatively rare in network with sufficient bandwidth and no or little congestion. Instead, the latency involved in transmitting data between clients and server play a significant role. Latency varies depending on a number of factors, such as the physical distance between the end-systems, as a longer distance means additional transmission length and routing required and therefore higher latency. Routing over the Internet may be extremely indirect, resulting in far more transmission length (and consequential latency) than a direct route, although the cloud gaming service OnLive has developed a solution to this issue by establishing peering relationships with multiple Tier 1 network Internet Service Providers and choosing an optimal route between server and user. In addition, insufficient bandwidth and congestion, even if not severe enough to cause losses, may cause additional delays regardless of distance. As with the hardware issues, packets that arrive slowly or not at all will make both the client and server unable to update the game state in a timely manner.

Online game systems utilizing a wireless network may be subject to significant lag, depending on the architecture of the wireless network and local electromagnetic interference impacting that network. Although radio propagation through air is faster than light through optical fiber, wireless systems are often shared among many users and may suffer from latency incurred due to network congestion, or due to network protocols that introduce latency. And, in the event of electromagnetic interference, transmitted packets may be lost, requiring a retransmission which also incurs latency.

Solutions

Solutions to lag vary depending on the cause.

Hardware

Local hardware lag is when your computer can't keep up with the game. If the skill effects seem to be slowing down, as if time is slowing down, then you are experiencing hardware lag.

If your local hardware is lagging the only solution is to turn down the graphics settings or upgrade the hardware.

Network

Network lag is when your network is having problems. If you notice a delay in your own inputs this is a type of network lag. It has several solutions depending on the cause of the lag. The most common cause is network congestion. If you or someone else using your internet connection is download this will cause lag. Regardless of the reason, our network optimization tool] may help. All of the solutions below assume that you've installed the network optimization tool already and have verified no one in your home is using your internet to download. Please be aware that downloading includes streaming movies or music, not just obtaining files/programs for your PC.

Always Lagging

If you are always lagging then it is just you. The server may lag occasionally but it doesn't lag all the time. This is likely due to your network configuration. The network optimization tool may assist with this, but it likely you are just too far from the server. You may want to consult your ISP for assistance in this matter or even switch ISPs.

Lag Spikes

If you are playing fine most of the time but randomly get a few lag spikes every now and then and you have installed the network optimization tool then this is likely packet loss. The game and server send packets back and forth. After sending a packet there is a delay while waiting for a response. If no response is received then the packet is resent. During this time the game may seem unresponsive. The most common cause of this is using WiFi or another type of wireless connection. You should try to use a wired connection if you can.

If you are on a wired connection and still get lag spikes it's likely due to your router, you should check that it is the latest firmware. Explaining how to do so is beyond this guide. Google your router model number and the word "firmware".

To exclude the router as a potential problem you should unplug the network cable from your modem going to your router and connect your PC directly to the modem. If you still experience lag spikes then the router is not the issue. If the lag spikes go away it is your router and you should replace it. Try to spend at least $100 on a new one, not all routers are created equal and while the packet buffer size is not a highly advertised feature it is very important for online gaming.

Lagging During Events/Woe

99.9% of the time this is your internet connection being too slow. If you are sure your connection is fast enough (at least 5Mb/s down and 1Mb/s up) then you are probably using WiFi. If a wired connection does not fix the issue contact your ISP.

If you think RO doesn't need 5Mbit/s down and 1Mb/s up for WoE/events then you should stop thinking you know everything. Events frequently will push out 3-5Mbit/s easily.

Server Lag

If everyone is lagging then it is the server. If a large number of people are lagging but not everyone then it is the connection leading to the server, but not the server itself.

Occasionally the server comes under DDoS attack and this will cause some lag. We have excellent DDoS filters that protect the server itself. The lag during DDoS attacks is caused by the filters having to sort out the bad traffic and only forwarding the good traffic to the game server. There's usually data incoming in excess of 5-10Gb/s during attacks, so there is a lot of data to go through. For comparison the legitimate traffic is only about 50Mb/s of that.

The server is connected with about 10 feet of copper GigE cable then straight fiber optic the rest of the way to your ISP. We have 8 processor cores with 16GB of DDR3 RAM and 8 solid state disk drives. Trust us when we say it's out of our hands when the server lags.