[ECOS] ECOS PPP terminated because of echo-request being rejected by peer

["Weili Yao" <weili_yao at trimble dot com>]

Hello, there:
    I have a device that is ECOS-based with Bluetooth connection to cell
phone (Sony-Ericsson T68i), and I have SIM card from T-Mobile in the
cell phone for the data connection. 
    When I established the PPP connection on the Bluetooth channel via
cell phone to T-Mobile ISP, the PPP would be up and running, but the
peer rejected echo-request made by ECOS like following (I decoded):

1) FF 03 C0 21 09 14 00 08 00 00 00 00 
    Sent to Peer:
   C0 21: LCP Protocol 
   09   : code (Echo Request)
   14   : ID (incremental)
   00 08: Length (including code, ID, len, and data followed)
   00 00 00 00: Magic Number
2) FF 03 C0 21 07 17 00 0C 09 14 00 08 00 00 00 00 
    Received from Peer:
    C0 21: LCP Protocol 
    07   : code (Code-Reject)
    17   : ID
    00 0C: len
    09 14 00 08 00 00 00 00: the original packet

    After 4 retries, the ECOS terminated the PPP connection. In that
period, the PPP was actually up and running. I just don't know why the
peer would reject the echo-request.

    In the net/ppp/current/src/pppd.c file, I then changed
lcp_echo_fails from 4 to 0 to ignore the LCP Code-Reject message from
peer. Then the connection will not be terminated by ECOS. The PPP
connection just works fine for me.

    Now my questions:

1) Is there any side-effect if I change lcp_echo_fails to 0 (i.e. ignore
the ECOH-Request reject message)?

2) The same SIM card is working fine with other cell phone (e.g. Nokia
6600) and GPRS/GSM modem without changing lcp_echo_fails. I don't see
the reject message. Did I miss something that is related to the cell
phone configuration?

   Thank you very much!

Weili Yao


--
Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss