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I've found a common subject in forums asking about using VPNs to reduce latencies between the gamers and the game servers. I've even found some blog posts confirming this.

From my understanding, using a VPN shouldn't reduce latency at all, unless routers somehow treat encrypted packets differently.

What's the truth here? Does the type of VPN make a difference?

SUMMARY OF COMMENTS/ANSWERS: While in the ideal net neutral world latency over a VPN should be greater or equal to latency over a public network, in the real world with crappy ISPs latency could actually be reduced by using a VPN. Pity! Especially because it leads to a "try it an see" approach on each particular ISP.

Unless we are talking about something like ISP provided VPNs (MPLS or similar) that can have a different routing and priority characteristics. But if you get one of these you are usually aware and paying for it. Not very likely in casual gaming scenarios.

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    A VPN might be able to get around traffic shaping/throttling. If you have a crappy ISP that slows gaming related activity. But evil ISP will almost certainly also be slowing VPN traffic.
    – Zoredache
    Mar 13, 2013 at 23:48
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    This is marked as a duplicate, but the other question is for office-to-office VPN; this is for gamers and game servers. All things being equal, this would be a duplicate. But things today are not equal. Your ISP (Comcast, ATT) will almost certainly be throttling your traffic (or at least someone's traffic, if multiple players are involved). The only way to prevent this (other than technological subterfuge) is through legislation that guarantees net neutrality. (Search for: vpn + traffic shaping {comcast|att})
    – michael
    Mar 14, 2013 at 3:12
  • Btw, encryption is different than VPN. You can have encrypted data that is treated differently than data over a VPN; e.g., comcast purportedly uses a network filter application (sandvine) that intentionally disrupts non-comcast user's connections (sending a TCP/IP reset (RST) flag); a VPN should prevent this type of "attack". (footnote: the fcc actually ordered comcast to stop doing this, but at some point they might author/pass legislation that allows/encourages it again.)
    – michael
    Mar 14, 2013 at 3:25
  • @michael_n Don't all VPNs use some kind of encryption? That's what I meant. You can of course send/receive encrypted data and not partake in a VPN.
    – Vinko Vrsalovic
    Mar 14, 2013 at 8:59
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    A MPLS VPN by the carrier may very well mean shorter latencies as it could be routed differently than normal traffic, and it could be prioritized. Although I do agree that most VPN solutions, like IPSEC over WAN will always add latency (although compression in theory can lower the latency for large packets). It's a shame I couldn't post an answer.
    – 3molo
    Mar 14, 2013 at 9:31

2 Answers 2

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Nope, a VPN can't alter physics to change the speed of light.

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    I would have thought there would be overhead that could actually possibly slow it down by a nanosecond or three, since there's encryption/decryption taking place at the endpoints... Mar 13, 2013 at 23:45
  • Yep, if anything it will perform worse.
    – MDMarra
    Mar 13, 2013 at 23:47
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    The gods unfortunately are unkind, and can choose to change the physics of the internets for us helpless mortals at their whim. The gods being of course Comcast (properly uppercased as canon dictates), and we must play by their rules. Masking our presence, trafficking in private networks, may stave off Their capricious ways, if only for the time being. Fare thee well, traveller.
    – michael
    Mar 14, 2013 at 2:58
  • It is possible to influence the path you take on the internet by tunneling traffic. This is all really dependent on how your ISP manipulates their traffic to/from their peers and upstream providers, so you might not gain anything, or you might take a different path that takes a longer physical path and actually increase your latency.
    – cpt_fink
    Mar 14, 2013 at 5:16
  • Assuming traffic is routed the same, the non-VPN latency is a lower bound. VPN can (at best) do epsilon worse. Mar 14, 2013 at 9:51
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A VPN could make a difference if it somehow traversed a route with less latency or hops than your "normal" network. This is rarely the case.

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  • But the VPN traffic will still follow the same route to the VPN endpoint that non encrypted traffic would and then it would still have to get from that endpoint to the game server. Even under ideal conditions, I can't imagine a situation where this would actually be true.
    – MDMarra
    Mar 13, 2013 at 23:48
  • @MDMarra, you are assuming a point to point VPN. It is rare, but occasionally my link between my home computer, and work computer will fail (Comcast is evil). But both my home computer and work computer are connected to a third machine on a different network via a VPN. It is remotely possible that I could get a better link via the VPN server then directly. But as Joel said, this is very rare.
    – Zoredache
    Mar 13, 2013 at 23:51
  • I'm not saying it makes sense, I'm saying it's totally possible Mar 13, 2013 at 23:52
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    @MDMarra Joel is correct, "It is totally possible" to send traffic with different destination IP's in different directions on the internet. Since your VPN tunnel has the tunnel head-end as the destination IP, you can be routed differently than a packet direct to the service IP. Only once your real packet exits the tunnel do both tunneled and non-tunneled packets have the same destination IP.
    – cpt_fink
    Mar 17, 2013 at 5:02
  • Of course that's how VPNs work, but under what circumstances will that be a more efficient path than the publicly routed Internet? The answer is somewhere between "never" and "almost never" which is the point of the question.
    – MDMarra
    Mar 17, 2013 at 12:43

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