downloading speed

Julio Arruda jarruda-gter at jarruda.com
Fri Apr 17 22:43:07 UTC 2009


Several windows in the same PC, doing file transfer in parallel, each 
get the same speed as one.
The speed is peaking at some specific speed every single time, and the 
several windows reach this peak.

I smell classic TCP window size  bumping into (bandwidth x delay).

Have you tried with iperf, using UDP ?




Mike Lyon wrote:
> Have him do a traceroute from his PC or router to where he is trying to
> download from. Where is it choking?
> 
> On Fri, Apr 17, 2009 at 3:21 PM, chandrashakher pawar <
> learn.chandra at gmail.com> wrote:
> 
>> Configuration
>> ================================
>> sh run interface FastEthernet1/3/1
>> Building configuration...
>> Current configuration : 351 bytes
>> !
>> interface FastEthernet1/3/1
>>  description CUST:xxx
>>  bandwidth 100000
>>  ip address 116.0.85.13 255.255.255.252
>>  no ip redirects
>>  no ip directed-broadcast
>>  load-interval 30
>>  negotiation auto
>>  no cdp enable
>> end
>> ========
>> No errors on the interface.
>> none of our customer on this router has complait us this issue
>> i have changed this to "negotiation auto" as suggested by one of our
>> member.
>> tommorow customer will test again and reply.
>> round-trip-time is good, no bacbone chocked.
>> Unit will not make bit differnce as: The customer tried troubleshooting the
>> issue after connecting laptop directily to the 100 mbps link.
>> In that case also the result was same.
>>
>> Regards
>> Chandrashakher Pawar
>> IPNOC
>> Customer & Services Operations
>> Tata communication AS6453
>> mobil + 91 9225633948 + 91 9324509268
>> learn.chandra at gmail.com
>>
>>
>>
>>
>>
>>
>>
>> On Fri, Apr 17, 2009 at 10:57 PM, Scott Weeks <surfer at mauigateway.com
>>> wrote:
>>>
>>> --- learn.chandra at gmail.com wrote:
>>> From: chandrashakher pawar <learn.chandra at gmail.com>
>>>
>>> We are level one ISP. one of my customer is connected to fast ethernet.
>>> His link speed 100,000 kbps. while downloading any thing from net he
>>> downloading speed donot go above 200 kbps.
>>> While doing multiple download he get aroung 200 kbps in every window. But
>>> when he close all the windows no change in downloading speed is observed.
>>> ---------------------------------------------
>>>
>>>
>>> You would need to add more info for any meaningful troubleshooting to
>>> occur.  Do you see errors on the interface?  Clear the counters and watch
>>> for a while.
>>>
>>> scott
>>>
>>>





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