IMSI Analysis
Claro Brazil Workshop April 5th, 2013 Dalia Guzman
IMSI – Use Case A VIP user has experienced a voice drop, and you have been requested to analyse the event, in order to provide a solution...
What to do?
IMSI – Details & Filter for analysis The details below are related to the voice drop. Create a filter for accordingly for your analysis:
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When – 02/04/2013 @ around 11.00 AM • Use Time Period filter for April 2nd, from midnight to midnight. Please beware that in the filter you have to use month/day/year, e.g. April 2 nd is 04/02/2013.
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What – CS Drop
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Where – Since we are filtering by IMSI, there is no need to filter by region, as IMSI normally would act on a very closed area. • However, a good practice is to choose the G e o g r a p h i c A r e a filter option“Use Bounding Box”.
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W h o – IMSI 724053908407878 • Use S u b s c r i b e r filter for above IMSI
IMSI – Individual Call Segments We can use this analysis to find all calls that have been done by that user we want to check. It gives us some information, like “start reason”, “completion”, “cell”, etc. – P l e a s e r u n t h e a n a l y s i s , an d o n c e y o u h a v e t h e o u t p u t t a b l e , p l e as e i d e n t i f y r e l e v a n t i n f o r m a t i o n ( IM S I, TASK drop call, sector it w as connected to, the type of s ervice, and the reason for discon nection).
IMSI – Individual Call Legs with RF Conditions We can use this analysis to find all calls that have been done by that user we want to check. It gives us some information as previous analysis, and also RSCP, EcIo, UE Tx power for that specific call segment. TASK – P l e a s e r u n t h e a n a l y s i s , a n d o n c e y o u h a v e t h e o u t p u t t a b l e , p l e as e i d e n t i f y r e l e v an t i n f o r m a t i o n ( IM S I, d r o p c a l l , s e c t o r i t w a s c o n n e c t e d t o , t h e t y p e o f s e r v i c e , a n d t h e r e a s o n f o r d i s c o n n e c t i o n , R SC P a n d E c / Io o f t h e s p e c i f i c c a l l s e g m e n t ) .
IMSI – Subscriber Comparison We can use this analysis to compare the behaviour / KPIs of different IMSIs (or show the KPIs of just one), in a period of time. TASK – P l e as e r u n t h e a n al y s i s , a n d o n c e y o u h a v e t h e o u t p u t t a b l e , i d e n t i f y t h e m a i n K P I s f o r th i s s u b s c r i b e r . I s h i s D r o p R at e t o o h i g h ? W h a t ab o u t n u m b e r o f d r o p s , d u r i n g t h e f i l t er e d p e r i o d , i s i t a h i g h number of drops?
This is a good analysis also to study the performance of (a) specific subscriber(s), for greater periods of time. For example, h o w w a s t h e g e n e r al p e r f o r m a n c e o f t h i s s u b s c r i b e r d u r i n g l a s t m o n t h ? You may also know which are the offender cells by running the analysis on next page…
IMSI – Drop Locations Inside the points folder, we can find the drop locations analysis. With this we can plot all locations for a specific IMSI for the drops. Once we located the drops in the map, using the spider tool we can drilldown each call TASK – Y o u m a y u s e t h i s a n a l y s i s a s w e l l t o f i n d o u t i f t h e r e ar e o t h e r s u b s c r i b e r s e x p e r i en c i n g d r o p s i n t h e a r e a ( s am e m a p b o u n d i n g s o f ~ 1 k m a r o u n d t h e d r o p a n d a p p l y a n e w f i l t e r w i t h i t , r e m o v i n g t h e s u b s c r i b e r
and extending the Time Period for 20 days, for example). Is this an area with lot’s of drops? Or is this a single e v e n t ? W h a t t o d o i n ea c h c a s e?
IMSI – Drop Locations / Call Spider In the first tab of the spider, we can see all properties of the call: IMSI, IMEI, start time, service, etc. TASK – P l e as e r u n t h e D r o p L o c a t i o n s a n a l y s i s i n t h e M a p , an d o n c e y o u h a v e t h e output, click on the spider optio n at the top o f t h e m a p t o o p e n C a l l S p i d e r. Once open, identify in th e Properties tab, the IMSI, Segment Start Time, Duration , Call Start Cell and Call End Cell, Servic e, ARFCN and Combined co des. W h a t w a s t h e r e as o n o f t h e d r o p ? W h a t o t h e r i n t e r es t i n g i n f o r m a t i o n d o y o u have in this table?
IMSI – Drop Locations / Call Spider
In the third tab of the spider, we can see the layer 3 analysis. In the first part, we can choose different charts to give us information of the call, like EcIo, RSCP, troughput, events, etc. We may be able to choose displaying the whole call or the first or last 15 seconds.
IMSI – Drop Locations / Call Spider In the third tab of the spider, we can see the layer 3 analysis. In the first part, we can choose different charts to give us information of the call, like EcIo, RSCP, troughput, events, etc. At the right side we can choose more options to show in the chart, in this example we are showing not only the cells in active set, but also the other PSC that were measured.
IMSI – Drop Locations / Call Spider In the third tab of the spider, we can see the layer 3 analysis. In the second part, we find the layer 3 signaling of the call. Each message could have more information, if we click the view icon. TASK – W i t h C a l l Sp i d e r o p e n , g o t o l a y e r 3 m e s s a g e s a n d i d e n t i f y w h e r e t h e d r o p m e s s a g e i s . O n c e y o u i d e n t i f y i t , c l i c k o n t h e f i r s t c o l u m n ( Vi e w ) b u t t o n , an d t h i s w i l l o p e n t h e c o m p l e t e d r o p m e s s a g e . W h a t v a l u ab l e i n f o r m a t i o n d o y o u h a v e t h e r e ? W h a t w a s t h e c e l l t h e u s e r w a s c o n n e c t e d t o b e f o r e d r o p p i n g ? W h a t w a s t h e E c / No , R SC P , a n d t y p e o f s e r v i c e b e f o r e t h e d r o p o c c u r r e d ? W h a t w a s t h e r e a s o n f o r t h e d r o p ?
IMSI – Drop Locations / Call Spider
Example of an open Layer 3 message, showing more details on the event
Template suggestion We have created a Template for IMSI analysi s , containing the above referred analysis. The template can be found in Data Explorer > Global > Templates (UMTS) > ClaroBR > IMSI Analysis Once you open the template, you will be prompted to include the three variables below, for analysis scope: >> Time Period – Enter period of analysis >> Service Group – Type of service (for example, voice, data, etc) for the drop >> Subscriber – Enter the IMSI object of analysis
