hi,
today i will finally
(begin to) structure the message handling in my current work on layer
3:
the message handling
functions consist of:
- message
cration
- message
sending
- message
en-queueing
- message
de-queueing
i deal
with interfaces (SAP):
- between
application and call control (MNCC-SAP)
- between call
controll and mobility management (MMCC-SAP)
-
between supplementary services protocol and mobility management
(MMSS-SAP)
- between sms
protocol and mobility management (MMSMS-SAP)
- between mobility
management and radio ressource (RR-SAP)
- between radio
ressource and layer 2 / layer 1 (let's call it RSLms-SAP)
additionally there
are interfaces:
- between
application and mobility management
- between
application and PLMN search
- to the sim
card
- to the
application
-
...
here is what i think
the messages should look like. please correct me if i am wrong or if you have
suggestions:
MNCC-SAP:
<gsm48_mncc
structure>
MMCC-SAP, MMSS-SAP,
MMSMS-SAP:
<gsm48_mmxx
structure>[<L3 message*>]
RR-SAP:
<gsm48_rr
structure>[<L3 message*>]
RSL-SAP:
<abis_rsl_rll_hdr
structure>[<L3 message*>]
* the layer 3
message consists of the gsm48_hdr structure + additional information
elements.
if a layer 3 message
moves from call control down to RSL and even lower, the inter-layer headers are
pulled and pushed. additionally there are pointers to the beginning of the
headers inside the message:
-
l1h
-
l2h
-
l3h
- layer 4
headers
- layer 5
header
the inter-layer
messages (MMxx-SAP and RR-SAP) will have no pointer to the message structures. i
think they also should not have them, since they have fixed length and are
pushed at the time they are sent, and pulled at the time they are
received.
any
suggestions?
andreas