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My internet plan is 512kbps unlimited and I get speed of average 64kbps but at night I used to get speed of 112kbps ..but recently my speed got normal like day time per my view usually at night their is less traffic so I should get good speed like before ... Due to good speed I download and upload at night and my average download+upload per month is 60gb or 70gb... Is it that my ISP people putting restriction on my download and uploads.. I am confused.

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And the question is? Whether your ISP is limiting your traffic? Maybe it would be a good idea to tell us: * Who is your ISP? * Where are you? * What kind of contract do you have? * What kind of connection are we talking about (UMTS, DSL, classical Modem-dial-in, ...)? – user unknown Feb 24 '11 at 21:07
Why don't you contact your ISP and ask them? – ChrisF Feb 24 '11 at 21:12
More likely all your neighbors are online at night too and clogging up the bandwidth in your neighborhood. – BBlake Feb 24 '11 at 21:28
@BBlake, That is not how it works. Your neighbor could have a different ISP or be on a different DSLAM or trunk and have nothing to do with your connection. Just because someone lives near you doesn't mean they are using shared bandwidth. DSL connections are shared at the equipment at the CO and even the same DSLAM can have multiple trunks. Most trunks are more heavily utilized between 8am and 5pm and are well below the 30% mark in the evening. This is not always the case, but is the norm. – MaQleod Feb 24 '11 at 22:52
@MaQleod - Or, there could be several hundred households in your neighborhood piggingbacking on one Comcast cable line. I dunno if I agree with BBlake that it's "More likely" but it's sure as hell possible. – Shinrai Feb 24 '11 at 23:17
up vote 1 down vote accepted

when your connection seems slow, connect a single computer directly to your modem, run a speed test, ping your DNS for about 30 minutes straight and look for loss and high latency. If speed issues go away, it is something on your LAN.

If speed issues persist then there are many many things that could be wrong. Generally an ISP will want to start with your specific circuit and do end to end testing from the CO to the NID directly. This is a good first step and will rule out any inside wiring in your building. If you still see issues then it can be anything from the lines on the street, the port your connected to, the card the port is on, the shelf the card is on, any internal wiring on the equipment, or even the trunk itself, to mention a few of the more common issues.

Anyone connected to a given DSLAM or CMTS has shared bandwidth through the trunk that feeds the equipment. In lower population areas, these trunks are usually DS3s, limited to 45 mbps for everyone at any given time. If its a higher population area, its probably an OC3 then you have 155 mbps. It doesn't take a lot to fill up that little bandwidth. Ask your ISP to check trunk utilization at the times of day you experience slowness. If its over 80% consistently you can request to have then add another trunk, or move you if they have more than one.

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Friend I cannot do all this their any simple steps..or is their any problem with my router...or in my computer..but why their is up and down in my speed day before yesterday my speed at night increased..but today at night it was slow..? – FrozenKing Feb 25 '11 at 6:11
Those are the simple steps, trust me on that. I do tier 2 support for an ISP and those are the simple steps we require of every customer before we start looking more deeply at an issue. Tier 1 at your ISP will ask you to direct connect as a start. If you can't do that, you're just going to have to live with your problem as that is the most basic of troubleshooting steps for speed issues and your ISP will not help you if you refuse that single step. – MaQleod Feb 26 '11 at 6:45

Most Internet connections use shared bandwidth at some point in the path, for ADSL this will be at the local exchange. The degree of sharing used to be referred to as the contention ratio.

Basically, if your neighbours become more active at night (their sons have all discovered World of Warcraft?) your speed can be affected.

It is possible for ISPs to use "traffic shaping" to throttle back certain types of traffic but I believe this is not the norm - or at least, ISPs rarely admit it. Some ISPs have been known to restrict usage by people who they believe are making unfair and excessive use of their broadband - but I think this mostly applies to a very small percentage of people.

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Ya you might be right because 2 months I used 111gb per month due to good speed at night...after that the problem started...but when i renew my net at start I get good speed at night but later it became like normal.. – FrozenKing Feb 25 '11 at 6:14
All internet connections have shared bandwidth at the trunk, but the trunk is rarely the problem. Traffic shaping is also rarely the problem. 95% of speed issues I diagnose are all caused by the person's LAN equipment. Every once in a while there are problems with a DSLAM port or an OC48 or such along the route causing packet loss for a number of circuits. You really need to do a lot of testing before you jump to the conclusion of a trunk issue or traffic shaping. – MaQleod Feb 26 '11 at 6:41
@FrozenKing: What do you mean by renew your net? You need to define your terms more clearly if you want someone to understand what you mean. Do you mean clear your arp cache and renew the DHCP lease? Do you mean unplugging your LAN cable and plugging it back in? Do you mean restarting your computer? do you mean repair your network connection within windows? – MaQleod Feb 26 '11 at 6:43
@MaQlead:I mean to say that when I renew my internet connection I get speed above 100kbps for just 2 or 3 days after that it becomes normal i.e 64kbps....I told my ISP peoples that I am having this net speed problems but they are too bad to help me ...please do u have any idea what to tell them so that they can help me ....thanks 4 rplying – FrozenKing Feb 26 '11 at 18:49

Firstly you should ask the ISP about speed commitment which is the smallest speed you can get with your internet plan. And about your speed is not the same at day and night, it's normal. My internet speed is better at night and my ISP opens more bandwidth to outside country at night too :) They have to do this because they don't have enough bandwidth for people.

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When I renew my net at start I get good speed later it becomes normal.. – FrozenKing Feb 25 '11 at 6:15

My ISP name is nivyah unlimited,i am using dial up connection

If you are using a dial-up connection using a modem then that is your reason that the connection is slow. You will need to upgrade to a (A)DSL connection for quicker speeds.

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