Help speed dropped drastically

[gamesbond]

Hi Guys I hope I'm doing things right.

I was having no problems with my connection speed until 2 nights ago, my speed dropped but only when doing ftp transfers or using programs such as Overnet or DC++. Web browsing works fine at the usual speed. When doing ftp transfers y usually had download transfers of around 30kBps but now it goes below 5kBps and my uploads work as usual. While using Overnet or DC++ it will not go over 1kps but other users download from me at normal speeds (around 28kBps) I checked my computer with adaware and spybot just a while ago to remove all spyware (had some :-p).

My connection is Cable and my speed (advertised) is supposed to be 2000kbps/512kbps.

My ISP is Megacable (mexico) which by the way have terrible customer support.

My OS is winXP which last night I just updated.

The TCP/Analyzer test results are as follows:

TCP options string = 020405640103030201010402
MTU = 1420
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput.
MSS = 1380
MSS is not fully optimized for broadband (although it might work well for slower connections). Consider increasing your MTU value.

Default Receive Window (RWIN) = 256960
RWIN Scaling (RFC1323) = 2 bits (scale factor of 4)
Unscaled Receive Window = 64240

For optimum performance, consider changing RWIN to a multiple of MSS.
Other values for RWIN that might work well with your current MTU/MSS:
507840 (MSS x 46 * scale factor of 8)
253920 (MSS x 46 * scale factor of 4)
126960 (MSS x 46 * scale factor of 2)
63480 (MSS x 46)
bandwidth * delay product:

Your RcvWindow limits you to: 10278.4 kbps (1284.8 KBytes/s) @ 200ms
Your RcvWindow limits you to: 4111.36 kbps (513.92 KBytes/s) @ 500ms
MTU Discovery (RFC1191) = ON
Time to live left = 49 hops

TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00000000

Thanks for your help!

[mccoffee]

You got to get mtu 1500 not 1420 are you running internet connection sharing or virtual private networking software??

[gamesbond]

thank you for your response, I'm really kind of new to all this, how can I change my MTU to 1500?

[gamesbond]

I found out how to change the MTU, the problem is that I can't get to go over 1472, it seems that's my ISP top MTU. I connecting directly thorugh a cable modem and its the only machine, I'm not sharing my connection. My problem still continues, any ideas?

Thanks

[mccoffee]

Try the following in cablenut

DefaultReceiveWindow = 256000
DefaultSendWindow = 32768
DisableAddressSharing = 1
InitialLargeBufferCount = 200
InitialMediumBufferCount = 480
InitialSmallBufferCount = 640
LargeBufferSize = 81920
MaxFastTransmit = 64000
MediumBufferSize = 15040
PriorityBoost = 0
SmallBufferSize = 1280
TransmitWorker = 32
FastSendDatagramThreshold = 4096
EnableFastRouteLookup = 1
EnablePMTUDiscovery = 1
IgnorePushBitOnReceives = 0
GlobalMaxTcpWindowSize =63008
MaxFreeTcbs = 8000
MaxHashTableSize = 16384
MaxNormLookupMemory = 5000000
SackOpts = 1
SynAttackProtect = 1
Tcp1323Opts = 0
TcpLogLevel = 1
TcpMaxDupAcks = 3
TcpMaxHalfOpen = 100
TcpMaxHalfOpenRetried = 80
TcpRecvSegmentSize = 1432
TcpSendSegmentSize = 1432
TcpTimedWaitDelay = 30
TcpUseRFC1122UrgentPointer = 0
TcpWindowSize =63008
MaxConnectionsPer1_0Server = 20
MaxConnectionsPerServer = 10
DefaultTTL = 64
DisableUserTOSSetting = 0
TcpMaxDataRetransmissions = 6
DefaultTOSValue = 92

[gamesbond]

should I post these values at cable nut?

[mccoffee]

nope

[gamesbond]

what should I do with all those parameters?

[mccoffee]

You download and install cablenut and u put those numbers in there.

[gamesbond]

sorry about that ;) I just typed the numbers you suggested into cablenut but things are the same. I've noticed that when my ftp or P2P connects it starts at a reasonable speed and then the speed drops fast to under 1k in my P2P program, in ftp it also drops from 30 to around 5kb. THanks once again for your help

[gamesbond]

I borrowed a notebook to check my modem and to see if my ISP had done anything to block P2P and ftp tranfers but with this notebook everything works at the usual speed, in other words it works without any speed problems.