[Hilo] Why TCP session information disappears automatically?


#1

[Hilo] Why TCP session information disappears automatically? In what case we need to use AT+KTCPDEL=XX to delete the session configuration? In what case the PDP context will be released by module itself?

Answer: About session configuration, it depends what kind of session are disconnected. See the following details:
/ Whenever the listener session is disconnected by you self or by network issue, the listener session configuration will be kept, so you need to use AT+KTCPDEL=xx to delete.
/ Whenever the child session is disconnected by you self, or by remote, or network issue, the child session configuration will be deleted automatically. So you don’t need AT+KTCPDEL=xx to delete.
/ When the client session is disconnected by you self, or by remote, or network issue, the client session configuration will be still kept. So you need to use AT+KTCPDEL=xx to delete.

About PDP context, it depends who made the disconnection. See the following details:
/ When the session is disconnected by you self, module will firstly close the session,
then check if no any other active sessions left, module will de-activate PDP context automatically, then IP address will be empty in AT+KCGPADDR.
But if there are any other active sessions left, then module will keep the PDP context. Then IP address is kept in AT+KCGPADDR
/ When the session is disconnected by remote side, then module will keep the PDP context anyway.
/ When network issue happens (E.g.GPRS detach), then module will release the PDP context.