Changes between Version 4 and Version 5 of Symbian_AP_Reconnection

Timestamp:

Feb 25, 2009 5:09:28 PM (15 years ago)

Author:

bennylp

Comment:

--

Symbian_AP_Reconnection

@@ -49 +49 @@
 Alternatively there may be a way to allow the stack to continue to run, updating the address information when necessary. This approach will require some specific features to be used, as well as some actions by the application when it detects that the IP address has changed. 
 
-The specific configuration and tasks will be explained below.
+The specific configuration and tasks will be explained below. Note we assume that the SIP and media sockets are bound to INADDR_ANY (0.0.0.0) and not to a specific interface IP address (this is the default behavior).
 
 
@@ -62 +62 @@
  So the solution is simply to trigger the re-registration by calling {{{pjsua_acc_set_registration()}}} function (after the new connection is up of course). The PJSUA-LIB will send re-REGISTER request, check the IP address/port in the response, and re-REGISTER again and update the account URI as necessary.
 
-
 ==== Media addresses update ====
 
@@ -72 +71 @@
 
  Note that at present there is no API to explicitly request the ICE media transport to initiate STUN Binding request immediately.
+
+ If ICE is not used, then at present there is no mechanism to update the IP address of media transport, nor the media transport will update its address even when STUN is used. The only solution would be to recreate the media transports and supply them to PJSUA-LIB with {{{pjsua_media_transports_attach()}}}.
 
 
@@ -84 +85 @@
  So this is an open issue.
 
- '''Changing of RTP/RTCP media addresses:''' ::
+ '''Task:''' ::
+ Changing of RTP/RTCP media addresses of ongoing call
 
+ '''Solution:''' ::
+ If ICE is used, then new STUN srflx address will be signaled in updated SDP offer, as long as:
+   - ICE media transport has detected that the IP address has changed (via the keep-alive above)
+   - the media was previously inactive, since if media has been active (hence ICE session is active), the SDP will contain only the used candidates and not all the list of candidates.
 
-
-== Scenarios ==
-
-=== Access point disconnection ===
+ Alternatively, '''we may not need to inform the new RTP/RTCP address at all'''. If the remote media endpoint has the capability to switch its RTP/RTCP transmission to the source address of the RTP/RTCP packets (note: PJMEDIA has this capability), then it should automatically switch its destination address to our new address.