This simpliefies the allocation process.
tfi_alloc is responsible to allocate a TFI, not a time slot.
The first time slot available depends on multislot class and on other
ongoing TBF (concurrent TBFs), so it is part of the allocation
algorithm to select it.
In order to use this feature, sysmoBTS requires option "-M", otherwise
the traffic is forwarded through socket interface.
This is essential, if PCU runs on processor of sysmoBTS. The reaction
time and delay of PDTCH frames could heavily degrade proper packet flow.
The slots are choosen in a way that later selection of slots for
concurrent TBFs will have the same downlink/uplink control channel
(PACCH).
This is required for polling acknowledge of new TBF assignment on PACCH.
The MS will always have the same PACCH uplink slot while beeing in packet
transfer mode.
Original code: c7e7f6868b
(The code was committed earlier, but got lost somehow.)
I added IMSI, so the paging request is sent in correct paging group.
Also I excluded rest octets from pseudo length.
It is tested and it work.
Some MS will leave packet transfer mode, if TAI is given, but no timing
advance control messages are sent on PTCCH. This could results in
permanent loss of larger packets.
It is essential to initialize the first_fin_ack variable.
Also it is essential not to free TBF, in case the final ack is not
received, but all frames have been acked. In this special case, we resend
the final block again and again (and poll), until we receive the final
ack.
It is quite essential. It shows how TBFs are related and helps to estimate
states and timers (timeouts) of the MS.
In order to use it, it must be defined by a switch at gprs_rlcmac.h.
Generic improvements to the csn.1 dissector include:
• Added a flag to the type descriptor structure so that any type can (potentially) flagged as xxx_OR_NULL. This was specifically needed for UINT_OR_NULL for the ms capabilities struct.
• Changed the CSN_SERIALIZE so that the length of the length field can be specified.
• For CSN_NEXT_EXIST removed the requirement that the next type be CSN_END, to allow truncation of multiple IEs.
• For CSN_LEFT_ALIGNED_VAR_BITMAP corrected the handling of bit_offset.
• Added a new type CSN_PADDING_BITS to make inspection of padding bits more convenient.
• Improved the CSN_RECURSIVE_TARRAY_1 to show the array index.
Improvements to the gsm_rlcmac dissector include:
• Rework the definition of EGPRS Ack/Nack Description so that the length IE (and absence thereof) is handled correctly.
• Added Padding Bits definitions to all PDUs
• Change the Multislot_capability_t and Content_t definitions to allow truncation at any IE
In this case the mobile has lost existing flows, so it make sense to free
them. The TFI(s) can be re-used immidiately, because they are not
associated by MS anymore.
Be sure to use always two bytes of length information for DL-UNITDATA,
even if the length of LLC data is less than 128 bytes. This way the data
has always the same offset from a 32 bit boundary.
This is required, since we may change slot allocation. In case of a
change, we do not want to be unable to change, if the same TFI on one of
the other slots is already in use by a different TBF (having same TFI, but
on different slot).
It is mandatory to support it because MS may request a single block.
In this case the network must assign a single block.
It is possible to force single block allocation for all uplink requests
on RACH. (VTY option)
Both flags can be used to determine wether assignment must be sent on PCH
or on AGCH. Before contention resolution is done, mobile will ignore
downlink assinment. When final uplink acknowledge was sent, the mobile
will go back to PCH after reception of akcnowledge.
Holger Hans Peter Freyther
Harald Welte