Download speed from the particular site is slow

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Oct 13th, 2009
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After many tests, I found that my 1811 decreases the download speed from a lot. Without any routers or with the other simple router, it is around 90-120K/sec, but when traffic comes through 1811, it comes down to 20K/sec.

So far, shows extremely slow speed, and shows half speed if the traffic comes through 1811.

I am sure that it is because of my setting on the router, but I cannot find out what to check.

Speed test ( always shows a good number. There is no internal congestion.

Could you help me to find out what setting I should take a look?

Thank you very much.

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Overall Rating: 5 (2 ratings)
Paolo Bevilacqua Tue, 10/13/2009 - 10:13
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Are you using pppoe ?

Richard Burts Tue, 10/13/2009 - 10:14
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Is it possible that the setting of duplex on the interface is mismatched? (or is there possible a speed setting issue on the interface?)

Perhaps it would be helpful if you would post the router config and the output of show interface.



ttanemori Tue, 10/13/2009 - 10:27
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Thank you very much for your reply.

I do not think there is mismatched interface, but I will do a double check.

I have attached my configuration file.

If you can give me any advices, that will be a great help.

Thank you again.

Paolo Bevilacqua Tue, 10/13/2009 - 10:30
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To being with, remove all ip inspect statements. These do not protect from anything.

then you do NOT need:

ip tcp adjust-mss 1452

ip virtual-reassembly

Also you will want be able to limit ACL and netflow on a single interface if possible.

ttanemori Tue, 10/13/2009 - 11:31
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Thank you very much for spending your time for me.

I know only SDM because I am a beginer of Cisco router.

I want to begin with removing ip inspection.

I went to "Interfaces and Connections" and opened "VLAN1."

Under Association tab, Inpect Rule for Inbound had SDM_LOW. I changed it to None, and I lost internet connection. Did I do something wrong? After I changed it back, it was restored.

Should I change SDM_LOW directly? When I go to "Applicaiton Secuirty" under "Firewall and ACL," SDM_LOW (policy name) shows several appications checked. Should I disable them here?

I am worried about any downtime to make a change. I do not understand why removing SDM_Low from VLAN caused internet disconnection.

Paolo Bevilacqua Tue, 10/13/2009 - 12:00
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Hi, do yourself a favor and stop using SDM now.

Not only is messing up you config, it also hides and prevents your from learning.

Just use telnet or SSH to the router and CLI, will become second nature after a little.


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