Re: [UDT] UDT-reliability issue (contd.. from the forrum)

[Yunhong Gu <yu...@la...>]

Hi, Sanjay,

It is hard for me to guess the problem given the limited information. We 
have used UDT to transfer much larger files. In rare situation, connection 
broken may happen due to timeout (one side does not receive any packets 
for a long time).

If your network bandwidth is very low (say, < 1Mbps), this may happen more 
often, because a conection may cause longer delay of packets delivery. The 
current setting of connection-broken timeout value is between 30 sec and 3 
minutes, depending on network RTT.

You may try to use a larger timeout value (see ./src/core.cpp, 
CUDT::rcvhandler).

In addition, make usre that the firewall between A and B will not 
intentially break the connection.

Thanks
Yunhong

Yunhong Gu, Ph.D., Research Scientist

National Center for Data Mining
University of Illinois at Chicago
SEO 700, M/C 249, 851 S Morgan St
Chicago, IL 60607-7045
T (312) 413-9576
F (312) 355-0373

On Wed, 26 Apr 2006, Sanjay Upadhyay wrote:

> Hi,
> Sorry to post here, since on forums I wasnt able to.
> I have problems in transferring large files. one thing I missed to inform, was that always the conection is from a client behind nat to a server.
>
> | A |  --->  {NAT} ---> [B]
> here A is the client sending a file to B server, using the UDT library.
> in such a situation at higher file sizes,  any one of the situation comes..
>
> 1) A keeps sending.. recvfile exits saying "connection is lost"
> 2) B keeps recieving.. sendfile exits saying "connection is lost"
>
> I have tried to figure out in side the code, but it isnt easy for me :)
> any help will be appreciated.
>
> For communications where A and B are locally connected (without a NAT) the communication is fairly good... I have tested from 1MB to 300 MB 10 times each.
>
> thanking you
> Sanjay Upadhyay
>
>
> Sanjay Upadhyay
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