Need a help please with capi

Need a help please with capi

Post by tall.ibrah » Fri, 03 Sep 2004 02:21:01

bonjour !

I'm starting witch CAPI & X25.
I'm developping a file transfer monitor with Oftp protocol (RFC2204).
My file is bigger than 128 bytes.
when i frangment and send 128 sized packets to capi, everything is ok, the
file is all transmitted.
But with 1024, 2048, etc, the first & second packets are confirmed by
data_b3_conf message.
the third packet is sent (data_b3_req is ok), but not confirmed by
data_b3_conf and this block my application (Oftp server & client).
the server traces that it received 0 size and is waiting
the client is blocked at the third packet

My Connect REQ:
- Called party number with 0x80 for Numbering plan Id.
- Calling party number : empty
- Called party subadress : empty
- Calling party subadress : empty
- B protocol : X25 over B channel
- B1 protocol : HDLC(0)
- B2 protocol : X.75(0)
- B3 protocol : ISO 8208 (2)
-BC,LLC,HLC,Additional Info : empty

I need seriously a help and thanks to any suggestion.

TALL Ibrahima (Paris)

Need a help please with capi

Post by anacel8 » Fri, 03 Sep 2004 14:27:04

Hi, Tall

I think that you must to verify the limit of the data length of your
protocol, in my case I am using V.120 asynchronous mode with V.42 bis
compression and I can't send package bigger than 128 bytes, if I send
bigger package I receive an error message, I am not sure about the
maximum size you can send, but I test it sending some package with
different size to find the maximum size that could be transmit.
Also its important to make sure that you are not sending a lot package
in a short time, becouse in acordance with the capacity of the channel
it can't suport all the packages transmition.

I hope it helps

Ana Cristina


Need a help please with capi

Post by tall.ibrah » Fri, 03 Sep 2004 16:18:15

Hi Cristina
I'm going to try your solutions (waiting sometime after every package).
The X75 protocol is effectively limited to 128 bytes but i think that capi
was able to handle itself bigger packages.
I tried also a variety of protocols but i had always some configuation

thanks !
TALL Ibrahima



Need a help please with capi

Post by Michael Me » Sat, 04 Sep 2004 02:25:26

Hi Tall;

Your connection request looks OK. You should be able to send a file with
this protocol setup. I can, so you can :)

If the program deadlooks then something with the program is probably wrong.

What you might want to look at is, how the program registers. If the maximum
data block length is smaller then the chunks of data you are trying to
submit capi will not send it. But capi should complain about it!

A Data B3 Confirmation only tells you that capi acknowledges the receipt of
the data. It does not say that it has sent the data to the remote peer yet.
What I want to say with this is : I.e. if you send off Data Requests and
straight afterwards a Disconnect B3 Request it may very well happen that
you disconnect before you have even sent any data at all. So give the
sending application a second between the last Data B3 Confirmation and the
Disconnect B3 Request. It worked for me.

I guess the reason why you get two Data B3 Conf's is simply because the
default 'window size' of ISO8208 is 2.