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Reply To: MC02d – ALU, help, please!

#64985
Denis
Guest

Hello, mr.Pix!
i think the only thing i can do – is to collect Abis traces.
but i have no experience in analyzis. so i already have questions

the first:
below you can see the Message “CHNRQRD” – channel required 🙂
all I’m able to see is Reference number and it = 19.
but how i can define the cause for the request? and TA? according to all sources this message must contain such info.

E-GSM 08.56 (LAPD 4.0.2) (LAPD) INFO (= info frame)
info frame
——-0 Address field ext. 0
——0- Command/Response 0
000000– SAPI 0
——-1 Address field ext. Last octet
0000001- TEI 1
——-0 Frame Type Information transfer format
0010011- N(S) 19
——-0 Poll Bit don’t poll
0101110- N(R) 46
E-GSM Alcatel Abis RMS, Release B9, ED03 Released (RMS) CHNREQIR (= Channel required)
Channel required
00001100 Message discriminator 12
G bits Common channel managment msg
T bit msg is to be/was considerd transp…
00010011 Message Type 19
Channel number
00000001 IE Name Channel Number
—–000 Time slot number 0
10001— C bits Uplink CCCH (RACH)
Request reference
00010011 IE Name Request Reference
00010011 Random Access Reference 19
00011— T1′ FN mod 32 3
***b6*** T3 FN mod 51 30
—11001 T2 FN mod 26 25
Access delay
00010001 IE Name Access delay
–000001 Access delay 1
00—— Spare 0

Many thanxes