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Networking The Internet

Ask Slashdot: What Is an Acceptable Broadband Latency? 396

Posted by timothy from the insert-rant-about-3g-dongle-speeds dept.
holmedog writes "A simple question with a lot of answers (I hope). I recently had issues with my DSL broadband at home, and after a month of no resolution, I was told 300ms latency (to their test servers) was the acceptable range for Centurylink 10.0Mbps. This got a shocked reaction out of me to say the least. I would think anything over 125ms to be in the unacceptable range. So, I have come to you to ask: What do you consider to be acceptable broadband latency and why?"
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Ask Slashdot: What Is an Acceptable Broadband Latency? More

Ask Slashdot: What Is an Acceptable Broadband Latency?

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  • Latency (Score:5, Informative)

    by Anonymous Coward on Tuesday March 06, 2012 @01:28PM (#39263051)

    I used to work for AT&T Uverse and over 200ms was enough to get a tech onsite to look at the problem.

    • Re:Latency (Score:5, Interesting)

      by Joce640k ( 829181 ) on Tuesday March 06, 2012 @01:39PM (#39263305) Homepage

      What exactly would he do? Latency is a function of all the hops between you and the other machine. I doubt they're going to reconfigure their network topology for a single user.

      • Re:Latency (Score:5, Insightful)

        by Joce640k ( 829181 ) on Tuesday March 06, 2012 @01:42PM (#39263359) Homepage

        PS: Talking of hops, tracert will show you how many hops are between you and their "test servers". Finding that out would be a good starting point.

      • Re:Latency (Score:5, Informative)

        by Anonymous Coward on Tuesday March 06, 2012 @01:44PM (#39263389)

        Your comment assumes that all the devices and media between locations were functioning properly. Latency can also be caused by bad wiring, bad modem, etc. Hell, even line noise can cause it because the line noise forces re-transmits.

        • Re:Latency (Score:4, Insightful)

          by JWSmythe ( 446288 ) <jwsmythe@nospam.jwsmythe.com> on Tuesday March 06, 2012 @03:05PM (#39264905) Homepage Journal

              You shouldn't have posted AC, you're actually right on the money.

              300ms could be that he has the line saturated with bittorrent traffic, or malware that he doesn't even know is there. It could be that his wireless connection is compromised, and the neighbor kid is downloading porn day and night. 300ms isn't acceptable, but likely isn't the provider's fault.

              Why, oh why, don't more people monitor their bandwidth? Maybe I'm a statistical whore, but I always have some sort of bandwidth graphing up.

        • Re:Latency (Score:5, Interesting)

          by holmedog ( 1130941 ) on Tuesday March 06, 2012 @03:49PM (#39265503)

          Hi! Thanks for the reply. To put some perspective - I've been troubleshooting this particular issue for ~1.5 months and have done the traceroute to make sure it is their issue and not mine. The 3rd hop hits one of their centers in a major city near me and that is the turning point.

          I didn't include this in the original story as I figured it was far to specific to my case.

          • Re:Latency (Score:5, Informative)

            by crafty.munchkin ( 1220528 ) on Tuesday March 06, 2012 @04:14PM (#39265789)
            You may think it's too specific however it's highly relevant information and should've been in the summary... if it's the third hop, there's nothing you can do at your place to fix it, and most of the above comments are redundant. This issue needs to be escalated within their networks team... *sigh*

            • Re: (Score:3)

              by Panaflex ( 13191 )

              And it's possible that they've simple oversubscribed and the latency is simply the router stuffing packets as fast as it can through the uplink. It could be a bad routing table, but not as likely.

              You need to do a 24 hour ping test and see if the latency has peak times or if the time is constant - this will usually tell you a lot and can be used when you speak with the provider.

            • Agreed. WITH Bittorrent currently running, I am averaging about 100ms of latency on Charter. At 150ms, I start having issues. While a couple of my hops did hit that, once again, I am running Bittorrent. At 300ms, with nothing else running, I would be looking for a new ISP. That is the type of latency I would excpect on satelite - I got friends on Hughes Net, and that is about what they average on a clear day. If your third hop has those high latency, then my thought is that your ISP doesn't have a fiber lin

          • Re:Latency (Score:5, Interesting)

            by denzo ( 113290 ) on Tuesday March 06, 2012 @05:55PM (#39267109)

            Hi! Thanks for the reply. To put some perspective - I've been troubleshooting this particular issue for ~1.5 months and have done the traceroute to make sure it is their issue and not mine. The 3rd hop hits one of their centers in a major city near me and that is the turning point.

            I didn't include this in the original story as I figured it was far to specific to my case.

            Have you tried IM'ing CTL_Joey at the dslreports.com forums? I used to have CenturyLink, and there were always connectivity issues cropping up. He was usually able to have my issues resolved, or at least explain what was going on.

      • Re:Latency (Score:5, Informative)

        by gknoy ( 899301 ) <gknoy@@@anasazisystems...com> on Tuesday March 06, 2012 @01:48PM (#39263483)

        No, but if you point out that the latency between everything up to your street is low, and you have massive latency over the last two hops, it helps show them that something isn't normal.

      • Re:Latency (Score:5, Informative)

        by rogueippacket ( 1977626 ) on Tuesday March 06, 2012 @01:52PM (#39263557)
        More often than not, latency is caused by congestion and not number of hops. Hops do introduce latency, but few modern applications need to go very far. So, whether the customer intentionally (bit-torrent) or unintentionally (malware) introduced this congestion is the first thing a tech will check for - usually by disconnecting the local network and running a speed-test directly from a laptop. The latency could also be caused by a local wireless network which is saturated, underpowered, or experiencing interference. So if the wireline speed-test passes, a wireless speed-test is likely to happen next with the tech standing right beside the modem.
        In the much more unlikely scenario that the latency is being introduced by the network itself, the technician will usually escalate the problem and check both the street-side cabinet (DSLAM in this case), and customer profile at the B-RAS deep inside the provider network. It is not uncommon to see a low-speed DSL profile applied to a poor quality local loop, or for the wrong Layer 3 profile to be applied by provisioning error on the B-RAS itself. Both scenarios would result in poor performance for the user, leading to congestion and therefore, latency.

      • Yes, but ISPs can make a big difference, as I mentioned on another post, I played an MMO 8 years or so ago, where the other players (pretty much all using TW, a few Comcast I think), complained of server lag at certain times, and experienced 500-1500ms latency. With my DSL connection, I was getting 75-100ms latency at the same time - not server lag. Some users were farther from the west coast servers than me, most were closer, pretty much all of them had higher-throughput connections than me. Local maintena

      • Where's the other machine, Mongolia? Most commercial ISPs have latency of 50 ms or less from coast to coast in the US and about 100 ms from the US to Europe. My numbers may be a bit out of date, but that's the rule of thumb we used at UUNET and Qwest. There are Service Level Agreements that provide that information.
        Yes, the last hop to the customer usually has the highest latency, but anything higher than 100ms for that is poor.

    • Re:Latency (Score:4, Interesting)

      by ByOhTek ( 1181381 ) on Tuesday March 06, 2012 @01:51PM (#39263535) Journal

      I had AT&T's DSL and did some gaming. I live in Ohio, and the servers were west coast. I typically had 75-100ms latency when the TimeWarner users were complaining about server lag and 500-1500mls latency. When they were down to 150-200ms (good for them), I typically hovered around 50-60ms.

      This was 7-8 years ago.

      IMHO, 300ms is unacceptable.

      My current cable gives me around 100ms average latency with SW:TOR.

      To me, "acceptable latency" comes with the type of service, and the distance to the target. This covers my views with servers in the continental US:
      With my previous DSL experience, I would be pissed with a DSL service that had 100ms or more latency except at the busy hours
      With cable, I expect upwards of 200ms, but the average should be closer to 100-150ms.
      With WiFi in the equation, I'd add a bit more, and be surprised if it were less than +50ms, but would still be pissed if it were more than +100ms.

      Mind you though, this is from anecdotal experience, YMMV.

      • Re: (Score:3)

        by Cyberax ( 705495 )

        Wow.

        I have 5ms (five milliseconds) from my home to my office. And they're about 10 km. apart, and not on the same ISP (there are 5 hops in the route between them).

        That's what I call 'good latency'. Now, a decent latency for most connections inside the country would be around 20ms. A decent latency to major out-of-country resources should not exceed 70-100ms. Hop across the Atlantic ocean should not add more than 120-150ms.

    • Re:Latency (Score:5, Informative)

      by mikael_j ( 106439 ) on Tuesday March 06, 2012 @02:00PM (#39263697)

      Yeah, I used to do tech support and anything over 100 ms or so for the first hop outside the ISP's network was likely to be escalated to a 3rd line tech if we couldn't solve it.

      Hell, right now I'm getting approximately 100-120 ms pings against random machines in the US northeast and around 190-200 ms for the west coast and I'm in northern Sweden...

    • I used to work for AT&T Uverse and over 200ms was enough to get a tech onsite to look at the problem.

      Most likely, you mean latency to a local test unit (perhaps where the uplink switches are).

      FYI, my latency is below 4ms to my ISP's speed test machine, about 46ms to 8.8.8.8 (google's public DNS), but around 150ms to slashdot. It depends a lot on the routers and the termination hardware as well as the number of hops.

    • How are you measuring latency? (Score:4, Interesting)

      by billstewart ( 78916 ) on Tuesday March 06, 2012 @02:40PM (#39264487) Journal

      The first question I'd have about high latency numbers is how you're measuring them. Lots of devices are pretty slow about responding to pings and traceroutes. (Big routers, in particular, tend to make that a much lower priority than routing packets or doing other useful work, and the ping response comes from the CPU. while the actual packet routing happens in ASICs.) On the other hand, doing a traceroute to some distant site can let you see a bunch of dubious measurements, and the smallest numbers tell you a lot because they're a ceiling on the latency of everything up to that point. I've also seen throughput measurement tools that think sending 18000-byte pings is a good idea, and they're not only hopelessly broken for measuring throughput, they get really entertaining latency results as well. The quick and dirty test is "ping 8.8.8.8" followed by "traceroute 8.8.8.8", which points you to Google's anycasted DNS servers.

      Traceroute also gives you some hints about routing - if you're in San Francisco, and your route to google.com is going by way of New York, something's weird with your ISP's peering. (I've seen that kind of thing happen - the user's ISP in Denver had recently moved, so their upstream link to the Tier 1 the user's headquarters used was down for a couple of months until they got a bigger access line built to the new site, and their ISP's other Tier 1 upstream didn't peer with the first Tier1 in Denver, and the San Francisco peering was overloaded back then so they were getting routed somewhere awkwardly far away.) But even so, it's really hard to burn more than an extra 120ms with bad routing unless you cross an ocean. (That's two extra round-trips across North America, or dancing around Europe; Asian users can occasionally get weird routes.)

      The next thing to do is be sure you're really really not running anything else while running your latency tests. Jim Gettys's "Bufferbloat" paper is really insightful, and you need to read it (but don't measure your latency while you're downloading it :-) A typical latency problem is that you're trying to download more bandwidth than something on your access line can support (such as your wifi router), so the device buffers traffic, and what you're really seeing is that bittorrent or big http transfer is filling up your wifi to maximize throughput, which is trashing your latency. Or alternatively, you've got something hogging your upstream, making it difficult for ACKs on downstream traffic to get through.

  • Latency (Score:5, Funny)

    by Anonymous Coward on Tuesday March 06, 2012 @01:29PM (#39263069)

    First pos... Dammit!

  • 300 Acceptable? (Score:3)

    by MachineShedFred ( 621896 ) on Tuesday March 06, 2012 @01:29PM (#39263071) Journal

    Maybe if you're coming from off-continent.

    300ms is the typical latency of an analog modem.

    • Re:300 Acceptable? (Score:5, Informative)

      by AvitarX ( 172628 ) <me&brandywinehundred,org> on Tuesday March 06, 2012 @01:41PM (#39263349) Journal

      I consider anything past 80ms to be slow for my cable connection (to 8.8.8.8).

      I just tested 19,17,18,18

      I previous test had a 60 something thrown in. This is via a boring home VPN router, shared connection, but under a dozen, and all light users.

      13 hops to 8.8.8.8 from here.

      33,34,33,63 to /.

      300 is what I get on hotel wifi, or my cellphone (to be fair, on my cell phone it goes up to 1000), as can hotel wifi become unusable, I swear most hotels must have 300+ rooms sharing a T1 line.

      • Thanks! I'd mod informative if I had the points. Just as a baseline, what kind of latency would you expect between computers in a room? I assume at some point the speed and quality of your router, NIC, drivers, etc have to start to matter.

        • Re:300 Acceptable? (Score:5, Informative)

          by DamonHD ( 794830 ) <d@hd.org> on Tuesday March 06, 2012 @01:56PM (#39263641) Homepage

          Generally 1ms or less.

          Pinging one of my servers in co-lo on the other side of London and traversing my moderate-speed (~4Mbps/1Mbps) ASDL only takes just over 14ms round-trip.

          Pinging my server in the US gives ~110ms.

          Singapore: ~270ms.

          Sydney, Australia: ~310ms.

          So I can get right round the globe and back in about 300ms, *starting* the trip over ADSL.

          Rgds

          Damon

          Rgds

          Damon

        • I ping 16 or 17 to google. .4 or .5 to my router 1 to my router's router.
          7-10 to the gateway on the other side of my modem.

        • Less than 1ms unless you are pushing around so much traffic that your router or switch is hosed. Even trashy consumer grade stuff should be able to do that. Honestly, for a wired broadband provider I personally would be upset at more than about 30ms to anyplace in the same state I am in, and really expect lower than that. Propagation delay in that sort of geographic area is so negligible that the only cause at that point of higher latency is that something is wrong on their network, whether it is with my l
    • Yup, my best pings were 300ms back when I used to play Jedi Knight online.

      • Hahaha, first thing I thought of when I saw the post about latency over a modem+phone line.

        I pwned at Nar Shaddaa. Tower and Drazen Isle were my favorite maps, though. Hell, I wish every multiplayer shooter had a game mode like the one in the Drazen Isle map.

    • Re: (Score:2)

      by cirby ( 2599 )

      200 ms from Florida to Tokyo, just now.

      235 ms from Florida to Sydney, Australia.

      If you're getting over 200 ms for connections across the US, something is horribly wrong.

      Normal speedtest results from Florida to Washington DC are in the 25 ms range...

  • Latency is the forgotten casuality... (Score:5, Insightful)

    by Anonymous Coward on Tuesday March 06, 2012 @01:31PM (#39263109)

    ...of the broadband wars. All consumers really seem to care about is faster download speeds, so networks offer it - by munging up their network so much that latency is measured in seconds. With the death of the network engineer, people just aren't educated enough to realize that part of the whole broadband experience is getting your packets sent and received fast, not just your GET or retrieve request getting all the data it asked for quickly. If you have to wait more than a second or two for your requests to even get there, then most people are gonna give up and try somewhere else.

  • Depends... (Score:4, Informative)

    by AdamTrace ( 255409 ) on Tuesday March 06, 2012 @01:32PM (#39263117)

    What are you using your connection for?

    If you're sending emails, then 300 is perfectly fine.

    Turn based games would be fine. Real time games would be rough.

    • Re: (Score:3, Informative)

      by sociocapitalist ( 2471722 )

      300ms is the serialization delay on a 56kbps modem. Doing any modern email with any sizable attachment would be painful at best and would more likely experience timeouts. Browsing the web with 300ms of delay would be painful.

      Keeping in mind that this delay is apparently inside his ISP network I think that there is no reason that he should accept 300ms unless his ISP is an inter-island carrier and the test servers are on another island or something.

  • Request an escalation of your trouble ticket. No reasonable person would expect 300ms latency as the norm.

    • Re:Escalate your trouble ticket (Score:4, Informative)

      by glop ( 181086 ) on Tuesday March 06, 2012 @01:39PM (#39263301)

      Yup, I'd say 10ms is not uncommon for modern
      The FCC Says:
      Results by ISP. The highest average round-trip latency among ISPs
      was 75 ms, while the lowest average latency was 14 ms.
      This is from "Measuring Broadband America - FCC" found on the FCC website.

    • Re: (Score:3)

      by na1led ( 1030470 )
      I would also think with those latency numbers you would have a hard time reaching 10Mbps. My guess is that you are a bit too far from the nearest POP which is cause attenuation in the line. Do a bandwidth test; see what the actual speeds are.

  • No one can define your requirements (Score:4, Insightful)

    by DoofusOfDeath ( 636671 ) on Tuesday March 06, 2012 @01:33PM (#39263139)

    We can't really tell you what's "acceptable". That ultimately depends on what you're using it for.

    Maybe the right question is, are you getting a worse ratio-vs.-price situation than is found in most markets in your country?

    Or are you asking whether or not the provided is in breach of the law because they're offering something so bad that their advertising is deceptive?

    • Or are you asking whether or not the provided is in breach of the law because they're offering something so bad that their advertising is deceptive?

      I see what you did there...

    • We can't really tell you what's "acceptable". Sure we can. As many others have pointed out here, anything more than about 20ms to your ISP is unacceptable. If you want to have *any* hope whatsoever of a successful VoIP call, you'll need 100ms end-to-end. Also, as others have mentioned, I've gotten less than 200ms ping times to freaking China!

  • It all depends on distance... (Score:4, Informative)

    by BagOBones ( 574735 ) on Tuesday March 06, 2012 @01:33PM (#39263149)

    I can't see 300ms being acceptable anywhere in North America unless you are on a satellite link, however if you are testing over continents then yes.

    Testing to the providers own test servers within the same country seems insane to be that high.

  • Nothing but the best for me. (Score:5, Funny)

    by fuzzyfuzzyfungus ( 1223518 ) on Tuesday March 06, 2012 @01:34PM (#39263161) Journal
    If there isn't a perfectly linear tube filled(emptied?) with hard vacuum between their GBIC and my GBIC, providing the lowest possible roundtrip time(that fiber crap can slow your photons by 30-50%), the connection isn't good enough.
  • Comment removed based on user account deletion
    • I agree with your comment. Below 50 is preferable, above 50 is bad but can't complain / have had worse, over 100 (domestically) is heads will roll
  • My 10Mbps cable gets 33/80ms at average/peak. A church I set up with 3Mbps DSL gets 60ms. My old satellite rig got about 500ms (less with modem uplink). Do they keep their test servers local, or does a tracert show a number of hops? 300ms is completely unacceptable for the first hop.

  • Location of Test Servers (Score:5, Insightful)

    by Bookwyrm ( 3535 ) on Tuesday March 06, 2012 @01:34PM (#39263177)

    Just where exactly are these 'test servers' in relation to you? What, exactly, was this 'test'? This seems a bit of a worthless test. It's entirely possible your DSL has less than 100 ms latency, but the delay is on the server end or the links in between. This is too vague a scenario to comment on.

    My feelings about 'acceptable' latency depend on how much I am paying for it, at what bandwidth, with what level of SLA, and for what purpose.

    • +1 on this. Without more information from the OP about the test nor its destination, it's nearly impossible to draw any conclusions.

      FWIW, I have CenturyLink 12.0mb/s DSL in the Seattle metro area. I just pinged their (CenturyLink's) local DNS server (205.171.3.x) from my router, and have latency consistently in the 20-25ms range - which I consider perfectly fine. (traceroute shows five hops total, bwt, all in the qwest.net network).

      Pinging Google's public DNS server, outside of qwest.net at 8.8.8.8, gives 7
      • Nerd fail. Was actually pinging from the wrong shell, which includes the latency of my laptop's wireless link. So the actual CenturyLink DSL latencies are 5ms or so less for me: 15-20ms to the local Qwest.net DNS server, 70-75ms to Google DNS.

        We now return you to more competent geek programming.

    • Re: (Score:2)

      by na1led ( 1030470 )
      I would run some traceroutes and see where the latency is at.

  • Depends on what you're connecting to... (Score:3)

    by Kenja ( 541830 ) on Tuesday March 06, 2012 @01:35PM (#39263187)
    If you're connecting to the house next door, I would expect 25ms or under. If you're connecting to a tentacle porn henti site in Japan, latency can be upwards of 128ms. In other words, there is nothing magic about broadband that reduces the size of the world or gets around the speed of light limitations.

  • For gaming 100ms is shit. For general browsing 300ms is still pretty poor, but not the end of the world on a cheap and nasty connection.

  • It really depends on 'to where you measure' and 'under what conditions' and 'what technology'. EG, satellite broadband will just have bad latency, period. Its the nature of the beast. And cellular/wireless can vary all over the place.

    But for fixed, land-line connections? I'd say well under 50ms of latency for the last hop, so perhaps 125ms latency max to an in-ISP test server (giving them the benefit of the doubt and assuming 75 ms latency to their test server because its somewhere in the middle of the

    • Re: (Score:2)

      by CAIMLAS ( 41445 )

      I've got latency under 200ms from a wifi connected laptop on one side of my house, over a VPN, to a friend's network 1800 miles away (probably closer to 3000 network miles) - to his laptop. 300ms is absurd.

  • Anything over 60ms screws up VoIP badly. Comcast builds in buffering in the modems to cause latency and jitter.

    These ISP's are getting as bad as the crap Dial up guys in the late 90's.

  • Latency has a couple of sources... (Score:5, Insightful)

    by Above ( 100351 ) on Tuesday March 06, 2012 @01:37PM (#39263239)

    When you say the word "latency" most tech-savvy folks think about the propagation speed of the technology (e.g. electricity in copper, or light in fiber), and thus assume it's basically proportional to distance.

    However, latency comes from other things as well. Serialization delay adds latency, and the lower the symbol speed the more it adds. Multiaccess media adds latency while waiting to transit. Multiplexing anything adds a small amount of latency looking for a time slot.

    The biggest culprit? Bufferbloat. This is a term that has been coined to describe the fact that many networking devices have entirely too much buffer. In the best case someone has sized the buffer for the max line rate that device may see (perhaps 25Mbps for your DSL modem, when your link is only 10Mbps), in the worst some misguided engineer thought "more == better" when figuring out how much to buffer, or just didn't care. There are a number of efforts to try and fix this poor situation, http://www.bufferbloat.net/ is the place to start. Basically buffers add latency. A small amount of buffering increases throughput, but beyond that it does nothing but increase latency and generally make the user experience crappy. When the link is full you need to drop packets _quickly_, because that's the signal to TCP to back off. Packet loss is a _good_ thing on a full link.

    Try running ICSI's Netalyzr (http://netalyzr.icsi.berkeley.edu/) which will attempt to estimate your uplink and downlink buffering. If you have a "router" in front of your DSL modem it may have some tuning, or "QoS rate shaping" that will help. If it's a device provided by your service provider you may not have access to the settings, and it may simply be configured wrong. With some vendors asking for a different model of device may help, with others, you may be screwed.

    The technologies involved should deliver 20ms latencies if properly configured. You should absolutely expect that, but getting them to acknowledge a problem may take latencies over 50ms. If your service provider thinks 300ms is normal, you need to escalate or move to a different provider.

    • He's spot on. The other question is how you're measuring the latency - lots of systems place a low priority on responding to pings, for instance.

    • Re:Latency has a couple of sources... (Score:4, Informative)

      by DamnStupidElf ( 649844 ) <Fingolfin@linuxmail.org> on Tuesday March 06, 2012 @02:57PM (#39264777)
      If your ISP won't help and you don't mind adding an additional gateway to your network you can generally fix bufferbloat by traffic-shaping your own traffic on a NAT router with custom firmware or even a PC running *nix. Drop upstream packets that exceed your average upstream, and drop inbound packets exceeding your average downstream (which can change throughout the day, making it kind of difficult to find the right limit). TCP/IP will handle the rest.

  • I'd have no problem with 300 most of the time, but I'm not a fan of multiplayer games that require twitch reflexes, nor do I do anything significant on OnLive.

    Another place you might have trouble is streamed content -- this is one of the reasons I do not like streamed content. I'd much rather use the model of "download the content, use it, and then discard it", which is much less sensitive to latency, lets you get higher quality regardless of bandwidth (as long as you allow the download time to be longer t

  • Mars? 300ms latency is getting into satellite territory.

  • I'm paying for a service, I expect no less than my minimum promised broadband.

  • My CenturyLink 10Mbps DSL in WA State delivers 65ms ping to a Google DNS server. I get 6-7ms ping to their gateway. It's rock solid unless my connection is saturated. They were significantly oversubscribed and were listing our area as having an "outage" for over a year before they finally got our backbone upgraded, but it's amazing now. You can ask them to switch you from Interleaved mode to Fast mode if your line is decent. That can reduce your ping time significantly. But it sounds like they have some oth

  • I consider anything >10ms to servers located within my ISP to be absolutely unacceptable. However I'm on a fibre link so my viewpoint is kinda skewed.

    When I was on a DSL link (1998 - 2002) if I got >50ms to servers at my ISP I started looking at what may have been clogging my link (in one case I did a data capture and proved to the ISP that one of their Cisco routers was misconfigured and spewing garbage) and then started planning to lay siege to the ISP.

    However given that you're dealing with an ISP t

  • I don't know what test servers you're referring to, but typically when I test a client's internet connection with speedtest.net using the automatically found best server I get results under 50ms. I would imagine anything over 100ms to a nearby server indicates some kind of network mismanagement.

    I also have clients using satellite connections. Their latency is typically around 750 to 900 ms.

  • If you have over 300ms latencies to servers inside your ISP's own network then I would definitely call that unacceptable. With my ISP and fastpath enabled I often get 20ms to servers within the same country. Anything over 60 and I wouldn't be able to feed my Counter Strike addiction ;)

  • I used to get better than that back in the dialup days using less than 56k-Flex from East Coast US to the Jolt servers in the UK. I would think broadband between you and your ISP's test server would be much less.

  • Personally I'd complain if it was anything over 50 ms for wireline. Wireless you are going to see higher; for satellite 300 ms is probably good (but I don't think you can get 10 mbps over satellite yet). With DSL I had ~13-20 ms reported to nearby test servers (well, ~70 miles as the car drives). Switched to U-verse recently, now I get about 22-30 ms to the same server on a bonded pair (interleaved). Don't think I've ever gone above 30 ms to test servers, but then I've only ever had DSL or a T1 at college (

  • Less than 30 forget about it.

  • Generally speaking, on a 10Mbps broadband connection I would expect 1-3 milliseconds to the first hop and a few milliseconds per hop additional inside the regional network.

    If you start hopping to other continents or if you're located on an island and have to have a satellite uplink or long haul inter-island or intercontinental fiber then you need to adjust your expectations upwards from there. Figure on a half second delay for a satellite link (accounts for both up and down) - 300 isn't enough for satellit

    • 1-3ms on the first hop? Unless I'm having a Lan problem the first hop is always 1ms The second and 3rd should have the highest latency increase since you can have invisible hops in the physical network between you and your ISP. Depending on how the ATM or other network is configured it might add 20 ms or only 5 ms. From there it should be a gradual increase at each hop.

  • Working at an ISP (Score:3, Informative)

    by andydouble07 ( 2344014 ) on Tuesday March 06, 2012 @01:48PM (#39263473)
    I just averaged together the data for a few thousand DSL circuits, and it seems that the average response time is in the area of 65 ms. Anything above 150ms is out of the ordinary. There are even a few CenturyLink circuits in there (reseller), and the average response time for those is a little higher, around 70 ms. Usually slow response times are because of an over-utilized circuit, but if that's not an issue here, then you should probably check the signal and margins on your modem or have CenturyLink send a tech to do so.

  • Some measurements (Score:2, Interesting)

    by Anonymous Coward

    I do have a 10 Mbps DSL at home with the following ping time statistics:

    First hop to ISP over DSL line in Finland: 22 ms
    City 500 km away within the same ISP network: 33 ms
    International connection to 10 hops and about 2500 km away: 50 ms
    International connection over some European countries and over Atlantic to New York (~8000 km): 125 ms
    Continuing journey from New York to Tokyo, Japan (lots of kilometers): 300 ms

    How far is their test server anyway?

  • A "test" server is probably hammered because it's a low end machine that's just there to test basic connectivity, and they direct a large number of people do "ping". They are essentially performing a DoS attack on their own test server.

    A better test would be to do a trace route to google or yahoo and see how long that takes.

    150 and less is decent to a server that's not being hammered, but latency for other things like Warcraft have additional things adding to it not just the connection so 300 is kinda hi

  • From

    http://www.dslreports.com/faq/694 [dslreports.com]

    DSL/Cable 10-20ms

  • Some points for comparison: https://wondernetwork.com/pings/ [wondernetwork.com]

    With only 282ms you can get a ping from Amsterdam to Hong Kong.

  • Latency depends on your destination. It is limited by the speed of light, and governed by how lousy the link itself is. It's how you sometimes get stories like the 500 mile email [ibiblio.org]For some reference points:

    A map of expected United States latency [fellowshipone.com] from some place in Texas.

    Often times your first hop on DSL will be slower... my own network right now shows 40ms to my ISP's gateway. 300ms is my ping time from Maine in the US to Australia.

    Another helpful source of references are looking glass servers [traceroute.org] that will let y

  • 300ms is usable, but not by much. Like in all things, it depends on what you're doing.

    For an ssh connection, that's almost unusable. I'd not want to use it for much of anything.

    For an AJAX web app, that will probably be unusable unless it was tested with such high latencies in mind and written by competent programmers.

    For gaming, you can forget about it. 300ms is about 50% more than maximum for what was playable for network games, 15 years ago, and it'll probably prevent gaming outright on many modern platf

  • I am on CenturyLink DSL, 1.5Mbps sadly, and I get about 100ms latency across the country. As good as 90ms from CO to AL. As much as 125 or so to locations further away.

  • I had a VPN customer on CenturyLink and a previous network engineer had put their home office LAN on 192.168.1.xxx (which is pretty common). The outlying offices were on 10.x.x.x subnets. One day, suddenly, no one could reach the home office file server. I discovered that there was a whole collection of computers with 192.168.1.xxx addresses on the WAN side of the routers. This, of course, broke the VPN links. He didn't just have them on that subnet but he had addressed one as 192.168.1.1 and up through a numerical sequence. When I finally got through to the chief admin guy (in Portland, OR) and told him he had internal IP addresses on a routable network he responded that the WAN side of our network was his INTERNAL network and he saw nothing wrong with putting a bunch of servers on those IP addresses. Nothing could convince him otherwise, either... because he was studying to take his Cisco Certified Network Administrator test.

    We readdressed the home office (that was fun!) and then moved to a better provider; one who at least would listen.

  • I live in a sublet house that has free CenturyLink DSL included in the rent (shared over wifi). The service is supposed to be ~768k, their lowest tier. I normally got about 600-700k so the speed was as advertised. However latency was normally fairly high (90-150ms to google) and any problems with the line (like a slightly bad filter) made it skyrocket. In addition any downloads on the connection would make latency shoot through the roof. One 240p youtube stream from one of my housemates would send late

    • Re: (Score:2)

      by wbr1 ( 2538558 )
      I just connect my LG optimus to the centurylink and ran a speed test. 214ms ping and 478k down. As a note someone else is using skype (audio only) on that connection right now.

  • Yea I would think you should be somewhere in the ~100ms range - and that's just barely adequate. To your ISPs server you should be getting under or around 60. I think for online gaming they say you should be under 80 but I could be wrong on that.

    For reference, I get 149ms ping on my cellphone with a shitty connection.

  • 10 ms (Score:2)

    by Kludge ( 13653 )

    I have a 1.5 Mbs DSL line to Cavalier telephone. Pretty slow throughput-wise, but my pings to 8.8.8.8 are 10ms.
    It's pretty good for gaming.

  • My phone does 100ms via UMTS or HSDPA. My cable connection at home is stable at 60-75ms typically, and I hate my modem for somany other reasons.

    125ms is below what should be a standard. Rotsa ruck getting it fixed.

  • When I had Speakeasy (RIP) I had latencies of around 10ms. With Century link they have been anything form 40ms to 200ms at various times. And this was to the next hop after my modem. I consider latencies about 20ms to be annoying. 100ms is way too high for the hop from my modem to their router.

    Hops after that are really hard to come up with values for since there is so much that can affect latency. But IMHO, if the broadband provider can't give you a link with less than 20ms latency from your modem to the n

  • http://www.linuxpromagazine.com/Issues/2011/127/Security-Lessons-Bufferbloat/%28kategorie%29/0 [linuxpromagazine.com]

    In this article, I’m not going to talk about an emerging technology (don’t get me wrong, I love new technology) but about something even more interesting: An emergent behavior that was never expected: bufferbloat.

    Bufferbloat is not a recent phenomenon; however, it has only recently been uncovered and understood, and developers will likely be grappling with it for some time. Additionally, this problem, if left unchecked, will make the Internet painfully slow to use, greatly reducing the availability of services. Remember, availability is one of the three legs of the AIC triad (along with integrity and confidentiality).

    So when people say "congestion causes slow networks" they are quite often right, but not for the reasons they think they are. Case in point: my Cablemodem ping times to www.seifried.org are nice and fast, until I saturate my uplink (with even just a single upload stream) at which point the latency increases to one second (in a semi-linear fashion over a few seconds, you can almost hear all the buffers getting fil

  • Why are so many of you posting like you know what you are talking about when you clearly don't know the difference and relationship between latency and bandwidth.

  • Filter (Score:4, Insightful)

    by SuperTechnoNerd ( 964528 ) on Tuesday March 06, 2012 @02:21PM (#39264113)
    I had a client with a similar issue. Turned out there was a phone in the basement he had forgotten about and did not have a filter. Installed the filter and he got between 60 - 100ms to his default gateway where before it was 250+ ms

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