[asterisk-r2] Too many network congestions

[Daniel A. Veiga]

    A few days ago a wrote asking if anyone had problems with "false"
network congestions. Nobody answered so I believe nobody had. But
it's a real problem to me, I get aboud 2-5% of the calls rejected
by this reason.

    Looking into the problem I found that I received a "network
congestion" when the other end detected we stopped sending DNIS for
more than about 200ms. My end never stopped sending, the problem is
the other end is not detecting them for some reason.

    I have no CRC errors, so I must believe the problem is not at the
interface layer, then it must be logical (data carried by the
interface level). I then looked at r2engine.c and found something
strange: When transmitting DTMF then higher tone is always
transmitted louder than the lower one. This is called twist and is
inherited from analog line's frequency response. But the twist,
which is implemented in openr2 library, is not used. The constant
DTMF_NORMAL_TWIST is defined, but when openr2_dtmf_tx_set_level()
is called it is not used. In fact a 0 is passed as the twist
parameter.

    Does anybody know if it was disabled for some reason, or it's just
a bug?

    Bye,


                                     Ing. Daniel A. Veiga
                                      ADV Technology SRL