doc/session-overview.txt

   1 Session API
   2 ***********
   3
   4
   5 Connection management algorithm basics
   6 ======================================
   7
   8 When a session is created, a sorted list of services is added to the
   9 session. The services are filtered and stable sorted according
  10 following rules:
  11
  12  - AllowedBearers (filter and sort)
  13  - RoamingPolicy (filter and sort)
  14
  15 A stable sorting algorithm maintains the relative order.
  16
  17 If a service is removed or added all sessions are updated according
  18 the above rules.
  19
  20 There are three triggers which lead to evaluate the connect
  21 algorithm:
  22
  23  - Session.Connect()
  24  - PeriodicConnect
  25  - Offline
  26
  27 Connect algorithm:
  28
  29               Session.Connect()     Offline
  30               PeriodicConnect        |
  31                        | Yes  +------+-------+  No
  32                        +------+StayConnected?+------ Do nothing
  33                        |      +--------------+
  34 Session.Change() ------+
  35                        |
  36                 +------+-------+
  37           +-----+EmergencyCall?+-----+
  38        Yes|     +--------------+     |No
  39           |                          |
  40         Connect to            +--------------+
  41         first available   +---+AvoidHandover?+---+
  42         Service           |   +--------------+   |
  43                        Yes|                      |No
  44                  +----------------+              |
  45              +---+In service_list +---+          |
  46           Yes|   |and online?     |   |No        |
  47              |   +----------------+   |          |
  48              |                        |          |
  49          Take that one                Take first in
  50                                       the service list
  51
  52 There are two triggers which lead to evaluate the disconnect
  53 algorithm
  54
  55  - Session.Disconnect()
  56  - IdleTimeout
  57
  58 Disconnect algorithm:
  59
  60   Session.Disconnect()
  61   IdleTimeout
  62        |
  63        +--- Session.Change()
  64        |
  65 +-----------------+    Yes
  66 |service not used +-------------+
  67 |by other session?|             |
  68 +------.----------+             |
  69        |No                      |
  70        |                        |
  71     Service.Disconnect()   Do nothing