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1st April 2010 at 21:07 #61827HostGuest
We will soon activate DTM feature in some cells in our network and test it after ALU B10 migration, so here are my questions:
– is Gs interface mandatory in DTM feature?
– what are the ways to test the good working of DTM?
– What NMO should we have ?
and finally which type of mobile could we use to test DTM?3rd April 2010 at 05:20 #61828pixGuest
gs is not mandatory. Only benefit of Gs is the ability for a subscriber to RECEIVE a phone call while browsing.
Without Gs, the user can still
1/ MAKE a phone call while browsing.
2/ RECEIVE and SEND data while in a voice call.
– Best way to test
without Gs, I would say you should perform a DL + UL FTP (download + upload) and establish a call while doing the FTP transfer.
Why UL+DL ? So that you have a TBF in both direction that should both be re-establish after the call setup.
You can see how the throughputs are impacted.
Of course, most users are going to use Web browsing rather than FTP… so you are actually testing the worst case scenario.
Then, while doing a call, start a FTP DL transfer.
Then, still during a voice call, ask someone to send you a MMS.
Also, during a call, change Routing Area : the routing area update should be transmitted over FACCH, and that should not impact the voice quality to much.
Durng all those tests, the MS should be GPRS-ATTACHED.
Leave it to NMO II, because you don’t have the Gs Interface.
– MS type
try the latest N9x from Nokia, those fellows support all latest features. You can check the technical specs of the phone, they’ll state if the MS is dtm capable or not.
pix3rd April 2010 at 11:20 #61829safarGuest
thr gs interface can we improve the PAGING SUCESS RATE.because here user will get i mean may be paging at a same time .so as per my knowledge by using gs interface u can improve paging because for voice and data paging is sync in this gs interface.
plz share abt gs interface ?4th April 2010 at 07:28 #61830pixGuest
i explained below that an user can RECEIVE a phone call while browsing, thanks to Gs interface.
Wthout Gs interafce, the paging is failed.
So yes, for this reason only, the Gs will improve the paging success rate. But on the other hand, it also induces an additional interface to configure, therefore a risk of misconfiguration or congestion, leading to paging losses.
The “synchronization” of the PS and CS paging doesn’t mean anything to me, (or I don’t know what it means.)
pix4th April 2010 at 09:39 #61831safarGuest
without gs interface u can do still ps and cs same time by using dtm .
only concern is with gs interface u can improve paging sucess rate.4th April 2010 at 20:36 #61832pixGuest
Exactly.5th April 2010 at 08:20 #61833HostGuest
thanks pix for these clarifications, last thing have u any idea about Gs interface usage by different operators allover the world?5th April 2010 at 08:35 #61834pixGuest
it is rather low, and it will tend to disappear. Indeed, the “CS-Paging while the MS is in Packet Transfer Mode” feature will tend to be done by the BSC more and more.
I’m sure that it is already done by most vendors (ericsson, etc.).
For example, alcatel is proposing this feature in B11.
(of course, the cost is not the same between adding an interface and upgrading the software…)5th April 2010 at 08:38 #61835pixGuest
I just need to add that the DTM feature itself, while available, is not so useful today. Maybe in the future, with new applications, that’d be more useful.5th April 2010 at 11:15 #61836BijoyGuest
I would like to add some more info.
There are 2 Terms known as “Paging coordination” or “IMSI Co-ordination”.
The MSC and SGSN provides BSS with information regarding which IMSI belongs to which connection and by coordinating the IMSI information from the CS and PS domains the BSS can make the paging handling more efficient. At both PS and CS paging the IMSI is used to coordinate that the paging message is always sent on a channel that is monitored by the DTM MS. That is, on PACCH when CS paging is performed in packet transfer mode, on FACCH when PS paging is performed in dedicated mode, and else on PCH/PPCH.
DTM and the IMSI coordination also has the benefit that non-DTM capable MSs can be reached by a CS page when in packet transfer mode regardless of network operation mode (regardless of whether the Gs interface is used or not). This functionality is available also when DTM is turned OFF in a cell, but the feature must be available. One exception is when the MS is involved in a pure UL transfer, Then DTM needs to be enabled in the cell to ensure that CS page is sent on the PACCH.
By sync,did you mean these co-ordinations or else?
Bijoy5th April 2010 at 20:25 #61837PixGuest
“One exception is when the MS is involved in a pure UL transfer, Then DTM needs to be enabled in the cell to ensure that CS page is sent on the PACCH.”
Do you know what is the reason behind this restriction ? I’ve never heard of it and can’t think of any reason why it wouldn’t be possible.
a non dtm MS can receive the CS paging on the DL PACCH, suspend its TBF and resume it later, can’t it ?
pix5th April 2010 at 21:03 #61838alcatel beginnerGuest
Friends, please tell me more about DTM feature. What is it ?
Thanks !6th April 2010 at 06:15 #61839BijoyGuest
Yes,but in that case DTM has to be enabled in that cell,isn’t it?
Bijoy6th April 2010 at 08:00 #61840safarGuest
In dtm ensbled network u will not get 100 % benefit because not all mobiles are dtm enabled while with gs interface u will get benefit of 100 %. Is it right?
In my network in normal case without dtm and gs interface ,while doing data downloading and somebudy tries to call then it shows not reacheble .so i want to ask here paging lost or what?
And bijoy,pix can u explain how ps paging coming?6th April 2010 at 08:21 #61841pixGuest
well, even without DTM in the cell, a MS is able to receive the CS paging in the DL PACCH. The only thing that matters is that the CS paging is forwarded onto the PACCH of this TBF.
This MS doesn’t even have to be DTM-capable to receive the CS Paging.
Well, that’s what you said below, but you said there is an exception for pure “UL TBF”… Don’t know why.
1/ yes Gs interface will benefit for all MS. But that is just ONE way to coordinate the Pagings. In B11, the BSC can do the coordination even without the Gs interface.
2/ yes, the paging is “lost” : the MS doesn’t answer to it.
3/ I don’t know what kind of applications would send a PS Paging. Perhaps some kind of “slow” and “bursty” applications (reception of emails ? blackbery stuff ? etc.)