[STDS-802-16] [Harmonization] Idle Mode Harmonization
To Phil and all,
I have some comments on the Idle mode harmonization draft (04/245).
(I was not able to attend the 8/9 (Mon) teleconference. I apologize if
my understanding is not correct, or the issues were already discussed.)
I. Comment 1: On the start of Idle Mode Timer and Idle Mode System Timer
- Related remedies in 04/245: 1
- Problem
In 04/245, it's not defined when the Idle Mode Timer and the Idle Mode
System Timer are to start. Unexpected behavior of MSS or BS related with
the two timers may happen.
- Proposed resolution
Define respective starting conditions of Idle Mode Timer and Idle Mode
System Timer. The condition for Idle Mode Timer should be an MSS event,
while that of Idle Mode System Timer a Paging Controller event.
Ex) Starting conditions for Idle Mode Timer: MSS's successful
reception of DREG-CMD message
Starting conditions for Idle Mode System Timer: Paging
Controller's successful transmission of DREG-CMD message when it is the
serving BS, or its reception of a notification from the Serving BS that
DREG-CMD has been successfully transmitted.
II. Comment 2: Can a paging controller respond to Idle Mode Timer?
- Related remedies in 04/245: 1
- Problem
It's impossible for a paging controller to comply with the "shall"
rule in the last sentence of the last paragraph in Remedy 1. Because
expiration of Idle Mode Timer is an MSS event, there is no way for a
paging controller to respond on an MSS event (although it may respond at
the time estimated from the expiration of Idle Mode System Timer).
- Proposed resolution
Delete "On expiration of Idle Mode Timer or" in the last sentence of
the last paragraph.
III. Comment 3: On incorrect descriptions when Paging Controller is the
Target BS (or the Serving BS)
- Related remedies in 04/245: 1, 8, 11
- Problem
A Paging Controller may be the Target BS. It is true at least when the
Paging Controller is the Serving BS and the MSS makes location update or
network re-entry with the same BS. In that case, the Paging Controller
shall not discard MSS service and operational information on MSS network
entry and resumption of Normal Operation, because it'll have to use
them. Also, the exchange of messages between the Target BS and the
Paging Controller (for example, new location notification message from
the Target BS to Paging Controller, MSS information from Paging
Controller to Target BS, MSS information request message from Target BS
to Paging Controller, MSS successful network re-entry notification
message from Target BS to Paging Controller, and request to stop
forwarding message from Target BS to Paging Controller) may either be
unnecessary or not be using backbone network.
Similar problems are there for the case when Paging Controller is the
Serving BS.
Many descriptions of 04/245 do not fit into the above two cases.
- Proposed resolution
Remove "via the backbone" or "over the backbone," in the remedies
since it is not necessarily the case.
Replace "to receive/send a backbone message to inform/notify," with
"to inform" or "to notify"
Replace "MSS information obtained from Paging Controller or other
network entity" with "MSS information retained, or obtained from Paging
Controller or other network entity."
Detailed resolutions are as follows:
1) Change the last sentence of Remedy 1 as follows:
"The paging Controller shall discard all MSS service and operational
information retained for Idle Mode management purposes on expiration of
Idle Mode System Timer, or on MSS network entry/re-entry or resumption
of Normal Operation unless it is the Target BS."
2) Change the second last sentence of section 6.3.21.9.2.1 in Remedy 8
as follows:
"..., the Target BS shall notify the Paging Controller of the MSS new
location information, the MSS shall assume the Paging Group ID of the
Target BS, and the Paging Controller may inform the BS at which the MSS
entered Idle Mode that ..."
3) Change the second to fourth paragraphs of section 6.3.21.10 in
Remedy 8 as follows:
"If MSS RNG-REQ includes an HO Indication and Paging Controller ID
TLVs, and Target BS is not retaining nor had previously received MSS
information, then Target BS may make an MSS information request of
Paging Controller and Paging Controller may respond. Regardless of
having received MSS information from Paging Controller, Target BS may
request MSS information from another network management entity.
Network re-entry proceeds per 6.3.9.5 except as may be shortened by
Target BS possession of MSS information which was retained, or obtained
from Paging Controller or other network entity.
For the Target BS to notify an MSS seeking Network Re-entry from Idle
Mode of re-entry process management messages that may be omitted during
the current re-entry attempt due to the availability of MSS service and
operational context information retained, or obtained from Paging
Controller or other network entity, the Target BS shall place an HO
Process Optimization TLV in the RNG-RSP indicating which re-entry
management messages may be omitted...."
4) Change the first sentence of the seventh paragraph of section
6.3.21.10 in Remedy 8 as follows:
"Regardless of the HO process Optimization TLV settings, the Target BS
may elect to use MSS service and operational information retained or
obtained from Paging Controller or other network entity to build and
send ..."
5) Change the eighth and ninth paragraphs of section 6.3.21.10 in Remedy
8 as follows:
"For a security keying process that has not been determined to be
omitted in the HO Process Optimization TLV settings, if MSS RNG-REQ
includes HO Indication and Paging Controller ID TLVs, and Target BS has
been retaining or has received MSS information, MSS and Target BS shall
use the embedded TLV PKM-REQ information and the re-authorization
process as defined in 7.2.
If MSS RNG-REQ includes HO Indication and Paging Controller ID TLVs, and
Target BS has been retaining or has received MSS information, the Target
BS may use the MSS information to build and send a REG-RSP management
message that includes Service Flow remapping information in New_CID,
Old_CID and Connection_Info TLVs."
6) Change the last sentence of the tenth paragraph of section 6.3.21.10
in Remedy 8 as follows:
"..., MSS may re-establish IP connectivity and new Serving BS may send a
request to the old Serving BS or other network entity to stop forwarding
pre-HO pending MSS DL data."
7) Change the twelfth paragraph of section 6.3.21.10 in Remedy 8 as
follows:
"The Target BS shall notify the Paging Controller of MSS successful
network re-entry and the Paging Controller may inform the BS at which
the MSS ..."
8) Change the first sentence of section 6.3.21.8.2 in Remedy 11 as
follows:
"The BS at which the MSS re-entered the network shall report to the
Paging Controller about MSS network re-entry."
IV. Comment 4:
- Related remedies in 04/245: 4, 5, 6, 7
- Problem
In terms of retaining service flow information, there seems to be only
two extremes: no retaining at all when Bit #6 is 0 and retaining
information of all service flows when Bit#6 is 1. There is no way to
trade-off between the two extremes.
- Proposed resolution
Differentiation of service flows according to the resource retaining
preference might be useful in making trade-off between the fast recovery
from idle mode and the overhead for retaining resource. Paging
preference of a service flow is not a perfect match to the resource
retaining preference. However, it is reasonable to expect that the
service flows of paging generation preference can be beneficial from
resource retaining. At the same time, Paging Controller or Serving BS
may reduce resource consumption by freeing up the resource associated
with the service flows of no paging generation preference.
Add following after the description on Bit #6 in Remedies 4, 5, 6, 7.
"Bit #7: Retain MSS service and operational information associated with
Service Flows having paging preference of 'paging generation'"
Thank you,
Jeong
--
Moo Ryong Jeong, Ph. D
DoCoMo Communications Laboratories USA, Inc.
181 Metro Drive, Suite 300
San Jose, CA 95110, USA
(408)451-4761 Tel
(408)573-1090 Fax