Underground: Hacking, madness and obsession on the electronic frontier - Part 71
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Part 71

This is one of the handover messages, logged with a CCITT7 link monitor, that he saw:

13:54:46"3 4Rx< sccp="" 12-2-09-1="" 12-2-04-0="" 13="" cr="">

BSSM h.o.r.eQ

BSSMAP GSM 08.08 Rev 3.9.2 (BSSM) HaNDover REQuest (h.o.r.eQ)

-------0 Discrimination bit D BSSMAP

0000000- Filler

00101011 Message Length 43

00010000 Message Type 0x10

Channel Type

00001011 IE Name Channel type

00000011 IE Length 3

00000001 Speech/Data Indicator Speech

00001000 Channel Rate/Type Full rate TCH channel Bm

00000001 Speech Encoding Algorithm GSM speech algorithm Ver 1

Encryption Information

00001010 IE Name Encryption information

00001001 IE Length 9

00000010 Algorithm ID GSM user data encryption V. 1

******** Encryption Key C9 7F 45 7E 29 8E 08 00

Cla.s.smark Information Type 2

00010010 IE Name Cla.s.smark information type 2

00000010 IE Length 2

-----001 RF power capability Cla.s.s 2, portable

---00--- Encryption algorithm Algorithm A5

000----- Revision level

-----000 Frequency capability Band number 0

----1--- SM capability present

-000---- Spare

0------- Extension

Cell Identifier

00000101 IE Name Cell identifier

00000101 IE Length 5

00000001 Cell ID discriminator LAC/CI used to ident cell

******** LAC 4611

******** CI 3000

PRIority

00000110 IE Name Priority

00000001 IE Length 1

-------0 Preemption allowed ind not allowed

------0- Queueing allowed ind not allowed

--0011-- Priority level 3

00------ Spare

Circuit Ident.i.ty Code

00000001 IE Name Circuit ident.i.ty code

00000000 PCM Multiplex a-h 0

---11110 Timeslot in use 30

101----- PCM Multiplex i-k 5

Downlink DTX flag

00011001 IE Name Downlink DTX flag

-------1 DTX in downlink direction disabled