My connection disconnects randomly

[Torrentus]

Hi, I m new to this forum , just discovered it a time ago.
I have a huge problem, my connection disconnects randomly when I mostly download via utorrent and then in the meantime watch a movie or play. After I come back to the desktop after some time, my connection is interrupted. I have no download speed and cant browse. I still send and get packets but only very few. Mostly I solve this problem to deactivate/activate my networkadapter that is on board. Sometimes when it doesnt help, I need to reboot my router (D-Link 804 ) and modem ( dunno the model but its a netopia), or restart my pc. Sometimes and dont recieve any packets but send few.
When I dont play or watch a movie the connection seems most of the time ok or sometimes it last longer.

My connection speed is from 8am to 8pm 24kbits up and down, 8 pm to 8 am 1,5mbits up and down and on weekends full 1,5mbits up and down.

I tried all the stuff, like patching to 100 half open tcp/ip connections, optimized it with tcp optimizer, set the global connections in utorrent to 100 and 60 per torrent, disabled dht, disabled upnp. Scanned my pc if they are some trojans, worms, spyware etc. nothing found, seems clean...

I called my ISP and asked them if there were some problems and that they should check my connection. They said everything seems normal...

Please help me, thx

[Torrentus]

Oh and I m using Vidalia with tor and comodo firewall

[trogers]

Oh and I m using Vidalia with tor and comodo firewall

Vidalia and Tor is an onion ring proxy server and should only be used if you are trying to overcome censorship by your ISP to some specific website. It should not be used for normal surfing as it will slow you down a lot.

Comodo firewall is known to slow down torrent downloading by more than half. Your router is already a hardware firewall. Turn off Comodo and see if you get a speed difference.

I tried all the stuff, like patching to 100 half open tcp/ip connections, optimized it with tcp optimizer, set the global connections in utorrent to 100 and 60 per torrent,

That is 60 connections per torrent. How many torrents are you running at the same time? Your router can only handle about 100 simultaneous connections. If you run 3 or more torrents at the same time, you will be overloading your router and that is why "my connection disconnects randomly when I mostly download via utorrent and then in the meantime watch a movie or play"

I set my BitComet to have max connections per torrent to 20 and I run only 5-6 torrents at the same time. More important, I also limit my torrent global upload speed to only half of what my ISP gives me. This will ensure all my downloads or surfing can send out receipt acknowledgement to the other side.

If you want to watch real-time movie, you need to stop your torrents, as real-time downloading of movie will use up most of your bandwidth.

[Torrentus]

First of all thanks for your reply,
The normal connection settings in utorrent is about 500 max global connections and 100 per torrent, when I do the speed guide it says I should turn it to 600 max connections and 120 per torrent. I think my router should handle that , it is a good router though. Anyway With my 100 max global connections and 60 per torrent its pretty low setting!?!?. What would happen if I set much higher half open tcp/ip connections like to 500? What are the after effects anyway? In SP 1 its set to unlimited only in SP 2 to 10...

But it only disconnects mostly when I play or watch a movie "offline", no streaming or online gaming.

Oh I forgot to mention that I ripped my Windows XP to a lite version, removed all the unnecessary ms products and services.


Anyway is there a way to check how many connections my router can handle and when the disconnect happens to see what it does to the router?

[Torrentus]

Forgot to mention that I m normaly running 8-10 torrents at the same time, even so if running 3-4 torrents its all the same...

[trogers]

Forgot to mention that I m normaly running 8-10 torrents at the same time, even so if running 3-4 torrents its all the same...

You may have set your global (max) connection per torrent high. But what is the default number of connections? This is the lower limit. Mine is at 10. So if there are too many connections at the same time, your torrent client will adjust where necessary.

My BitComet has a 'Statistics' section that displays the following:

Overall Tasks: Total:86 / Running: 7

TCP Connections: Established: 92 [MAX:128] / Half-Open: 100 [MAX:88]
LAN IP: 192.168.1.2
WAN IP: 124.120.xxx.xxx
Listen Port of TCP: 5xxxx
Listen Port of UDP: 5xxxx
Windows Firewall: Added
NAT port mapping: Disabled

Overall Download Rate: 47 kB/s Max Connection Limits: 20 per task
Overall Upload Rate: 30 kB/s Upload slots: 14

Disk Cache Size: 23.50 MB (Min: 6 MB, Max: 24 MB)
Free Phys Mem: 464.06 MB (Min: 30 MB)

Disk Read Statistics: Request: 155016 (freq: 2.0/s), Actual Disk Read: 131774 (freq: 2.0/s), Hit Ratio: 14.9%
Disk Write Statistics: Request: 280960 (freq: 2.5/s), Actual Disk Write: 38901 (freq: 0.2/s), Hit Ratio: 86..1%

[trogers]

Here is a Router Chart listing the max. simultaneous connections of various routers:

http://www.smallnetbuilder.com/compo...189/chart,124/

[Torrentus]

Thanks for your help but it dosent solve it.
I just set my global max connection to 80 and the maximum connection connected peers per torrent to 20, running only 5 torrents, it still collaps after 1-2 hours without gaming or watching a video... after that my connection is still alive for 1 hour , can browse but download is pretty slow. After some time it will completly disconnect. I can only deactivate/activate my networkadapter on board, flush the dns, and reset the router / modem.

After that my connection is back to normal but wont long last. After some time the problem occurs much faster than the first try.

Its very strange, I dont know where the problem is, just tried everything and the odd thing is , this problem started since 1 month ago. In the past I had that problem but it was rare and it vanished after a week. Now I have that **** through the whole month and it sux ;(

[trogers]

First thing to do is to see if your are tweaked to your bandwidth.

What speed did you pay your ISP to give you?

Post your TCP Analyzer report.

[Torrentus]

My ISP is broadnet, pay 50 € per month and its with Voice-IP telephon. Yea I m using a Voice-IP telephon forgot to mention...

I m right now at work, will post it when I come home.
Keep you updated, thx

[Torrentus]

Ok back at home, here is my TCP Analysis :


TCP options string = 0204057a0103030101010402
MTU = 1442
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput. If you are using a router, it could be limiting your MTU regardless of Registry settings.
MSS = 1402
MSS is not optimized for broadband. Consider increasing your MTU value.
Default TCP Receive Window (RWIN) = 128984
RWIN Scaling (RFC1323) = 1 bits (scale factor of 2)
Unscaled TCP Receive Window = 64492

RWIN is a multiple of MSS
Other RWIN values that might work well with your current MTU/MSS:
515936 (MSS x 46 * scale factor of 8)
257968 (MSS x 46 * scale factor of 4)
128984 (MSS x 46 * scale factor of 2) <-- current value
64492 (MSS x 46)
bandwidth * delay product (Note this is not a speed test):

Your TCP Window limits you to: 5159 kbps (645 KBytes/s) @ 200ms
Your TCP Window limits you to: 2064 kbps (258 KBytes/s) @ 500ms
MTU Discovery (RFC1191) = ON
Time to live left = 46 hops
TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00000000 (0)

[trogers]

Who is your ISP and what speed are they supposed to give you?


Your MTU is off. Try the following with TCP Optimizer:

General Settings tab:
Custom settings - check
Modify All Network Adapters - check
network adapter selection - your NIC
MTU 1500
TTL - 64
TCP Receive Window - leave blank
MTU Discovery - Yes
Black Hole Detect - No
Selective Acks - Yes
Max Duplicate ACKs - 2
TCP 1323 Options:
Windows Scaling - uncheck
Timestamps - uncheck

Advanced Settings tab:
Max Connections per Server - 10
Max Connections per 1.0 Server - 20
LocalPriority - 1
Host Priority - 1
DNSPriority - 1
NetbtPriority - 1
Lan Browsing speedup - optimized
QoS: NonBestEffortLimit - 0
ToS: DisableUserTOSSetting - 0
ToS: DefaultTOSValue - 80
MaxNegativeCacheTtl - 0
NetFailureCacheTime - 0
NegativeSOACache Time - 0
LAN Request Buffer Size - 32768
Then select "Apply Changes" and reboot to take effect

After reboot, post a new TCP Analyer to see if your MTU increases.

[Torrentus]

After I change the settings you posted, my connection was too slow, I couldnt even browse. I must changed it back to the default optimzed settings....
Ok here is the result with the settings you posted before:

TCP options string = 0204057a0103030e01010402
MTU = 1442
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput. If you are using a router, it could be limiting your MTU regardless of Registry settings.
MSS = 1402
MSS is not optimized for broadband. Consider increasing your MTU value.
Default TCP Receive Window (RWIN) = 1073725440
RWIN Scaling (RFC1323) = 14 bits (scale factor of 28)
Unscaled TCP Receive Window = 65535

RWIN seems to be an excessively large number. If you're on a line lower than 20 Mbps (that is not satellite), consider using a smaller value.
For optimum performance, consider changing RWIN to a multiple of MSS.
Other RWIN values that might work well with your current MTU/MSS:
515936 (MSS x 46 * scale factor of 8)
257968 (MSS x 46 * scale factor of 4)
128984 (MSS x 46 * scale factor of 2)
64492 (MSS x 46)
bandwidth * delay product (Note this is not a speed test):

Your TCP Window limits you to: 42949018 kbps (5368627 KBytes/s) @ 200ms
Your TCP Window limits you to: 17179607 kbps (2147451 KBytes/s) @ 500ms
MTU Discovery (RFC1191) = ON
Time to live left = 46 hops
TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 01010000 (80)
Precedence (priority) = 010 (immediate)
Delay = 1 (low delay)
Throughput = 0 (normal throughput)
Reliability = 0 (normal reliability)
Cost = 0 (normal cost)
Check bit = 0 (correct, 8th checking bit must be zero)

DiffServ (RFC 2474) =

[mccoffee]

just click on file and then default settings apply changes and reboot. On the router make sure your firmware is up to date the mtu is set to 1500 or 1492 for pppoe mode.

[Torrentus]

I know how to set it to default... , I think my router or modem are damaged thats why its ****ed up...

[Torrentus]

Ok, I found out a strange thing...
My connection dies after some minutes when I start even a http download no torrent download. Its pretty strange...

Any other suggestions? Where can I change the MTU in the router???

[mccoffee]

make sure you allowing ping/icmp/wan request though the router and software firewalls without ping getting though it could be why your downalods are getting drop since that message helps both computers to keep the connection alive.