- This topic has 9 replies, 1 voice, and was last updated 13 years, 1 month ago by pix.
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14th December 2011 at 20:04 #67634PeterGuest
Hello, dear experts!
I have one question not about network equipment but about mobile phones, moreover – the most popular one (at least in the nearest past) – NOKIAs.
We get lots of complaints from our subscribers which use Nokia (different models) that during call establishment on the screen they saw open lock (near the picture of green handset). While the call the lock is not being showing but right after the end of call that lock shows itself again. And it is still open. All available sources (internet mostly) say that it means their operator disable ciphering.
I work in operator company and i’ve checked myself that ciphering (A5/1) has already activated for all BSCs.
And my question is:
What does that lock mean?Many thanks again
15th December 2011 at 08:03 #67635VanGGuestHi Peter,
what is your network vendor and in which Nokia’s models this occurs?
BR,15th December 2011 at 08:29 #67636PeterGuestHello, VanG!
Network vendor is ALU (B10 now).
Phones are: C1206, 5530, N7, 6230i.Actually, we never that lock closed (locked) :)))
We check *Ciphering Hypotesis* in following way: connect 6230i to TEMS (and later – NEMO) and made some calls. While the call establishment we made some photos of that open lock and then from L3 messages show messages CIPHERING_MODE_CMD and CIPHERING_MODE_COMPLETE.
So it’s not ciphering issue :))
What is this?Thank for help in advance!!
BR, Peter
15th December 2011 at 10:02 #67637pixGuesthi,
in the message CIPHERING_MODE_COMPLETE
what is the actual ciphering mode chosen ?
even if the call is not ciphered, those “ciphering” messages are still exchanged. It is used to choose among A5/0, A5/1, A5/2 and A5/3. MS, BTS and MSC have to all agree on the same cipher.
A5/0 = no cipher.
Regards
pix15th December 2011 at 13:09 #67638PeterGuestHello, Pix!
Thanks!
Excellent note – we saw those messages but didn’t check all themI’ve done it only now.
It’s always A5_1 – the only ciphering algorythm possible in our network (BTS settings)
Thank you very much!
15th December 2011 at 22:36 #67639pixGuesthi,
it seems the nokia phone do know what its encryption status…
blog.taddong.com/2011/02/does-your-phone-warn-you-when-it-is-not.htmlan open lock means there is no encryption.
so either the phone is not behaving correctly
… or your network is not behaving correctly
… or you misread the Ciphering messages ?could you copy and paste the content of the ciphering complete message here please ?
regards
16th December 2011 at 08:13 #67640DOMOXGuestHI, CAN ANY INE TELL ME HOW TO FIND OUT THE PARAMETER IN NOKIA SYSTEM REGARDING CIPHERING
16th December 2011 at 19:49 #67641PeterGuestHello!
Thanks a lot for very interesting material!
The next portion of collected facts:
1) in our country there are three operators: one use ericsson equipment, other – ericsson + huawei and we use ALU. In all networks Nokia 6230 behaves itself in the same way – shows open lock at the beginning of call
2) here are messages from TEMS:
MS1
Ciphering Mode CommandTime: 13:39:16.39
Frame number: 670251Skip indicator : 0
Protocol discriminator : (6) Radio resources management messages
Message type : 53
Cipher Response
CR : (1) IMEISV shall be included
Cipher Mode Setting
Algorithm ID : Cipher with algorithm A5/1
SC : (1) Start cipheringMS1
Ciphering Mode CompleteTime: 13:39:16.42
Frame number: 670251Skip indicator : 0
Protocol discriminator : (6) Radio resources management messages
Message type : 50
Mobile identity
Odd/even indication : (0) Even number of digits
Type of identity : (3) IMEISV
Identity digits (BCD) : 3574450069750300As far as i understand it mean that ciphering had been established successfully.
What do you think?
Thank you very much for help!
BR, Peter!
17th December 2011 at 17:07 #67642paraHOGuestPeter
do you have the raw data (hex) for the entry below that you posted?
2) here are messages from TEMS:
MS1
Ciphering Mode CommandTime: 13:39:16.39
Frame number: 670251Skip indicator : 0
Protocol discriminator : (6) Radio resources management messages
Message type : 53
Cipher Response
CR : (1) IMEISV shall be included
Cipher Mode Setting
Algorithm ID : Cipher with algorithm A5/1
SC : (1) Start cipheringMS1
Ciphering Mode CompleteTime: 13:39:16.42
Frame number: 670251Skip indicator : 0
Protocol discriminator : (6) Radio resources management messages
Message type : 50
Mobile identity
Odd/even indication : (0) Even number of digits
Type of identity : (3) IMEISV
Identity digits (BCD) : 357445006975030017th December 2011 at 17:10 #67643pixGuestpeter,
thanks for the detailed info 😉
now it seems the MS is not behaving properly. The next step would be to contact Nokia and check with them.
anyway, you can already re-assure your subscribers telling them that their connections are indeed secured with the best ciphering (or almost…) and that the “open lock” is not meaningful.
thanks again for sharing your problem, it’s interesting !
Pix
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