SS7 Signaling Basic
Transcript of SS7 Signaling Basic
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TELECOM BASICS
CCS Associated
CCS Quasi associated
CCS Non associated.
E1a) 256 bytes per frameb) 8 bits Each TS in E !ramec) ".25uS time ta#en by one framed) Tota$ 8""" frames in %ne Second
Voice Theorma) &oice !re'uency ( "" to "" *+ , band-idth /""" *+b) Ny'uist theorm 0in 8""" samp$in1 rate re'd /"""32 )c) %ne Samp$e 8 bits 4eprsntation of 256 &oice ee$s , 2 po- 8 256)d) 8""" samp$es in %ne Sec 8 bits 3 8""" 6/""" bits per sec re'uired
Erlanga) 7nit of Traffic descibes tota$ traffic o$b) Er$an1 usy time for c#ts 9 A$ Time 5c#t < 8. Er c#t < 2.5 Er E < ="c#t < 2". Er "2 E < /8 Er 5 E <
E1 Physical Interfacea) "th TS used for synchroni+ation """)
b) 0odes of %peration. 7nframed < No TS at a$$
2. !ramed < A$$ 2 TS used for data .0u$tiframe < " TS for sync, rest for datac) it ?? < & , it ?"? < "(". &
CAS Channel Associate! Signalling "a) 7ses @NAN Si1na$$in1 &oice fre'uencies )
b) Si1na$iin1 Associated in that E on$y < TS 6 ine Si1. And TSA$$ 4e1istered Si1na$$in1
CAS Line Sia) 7ses TS !4EE , S@EB
ABCD Fwd
10XX
00XX
00XX
00XX
00XX
10XX 0/
Ist Frame
II*d Frame
----
----
1.t Frame
CAS Registere! Signallinga) 7ses oice TS for 4e1istered Si1na$$in1 .b) Types ; ECA@C , T0! , 42 Semi C , 42!u$$y Cc) 420! < 42 0u$ti !re' !u$$y Comp$ed Ac# 4e'd)d) 0! < Combination of 2 !re' to represent one info
CAS Registere! Signallingr2 A Bwd S(3- r2 B Bwd S(3-
1 Se*d Ne4t D(3- + Ca*3ed N5-
+ Restart Ca66ed L(*e B7s8
Ca*3e 59er 3r2 B % C5*3est(5*
% CLI . :*a665cated N5-
. Se*d Cat 5; A Part8 < N5rma6 s7's ;ree
< Sw(tc t5 s2eec
# Se*d 6ast '7t + d(3(ts
, Se*d 6ast '7t d(3(ts
= Se*d 6ast '7t 1 d(3(t
r2 1 Fwd S(3- r2 II Fwd S(3-
1 D(3(t >1> 1 ?rd(*ar8 S7's
+ D(3(t >+> + Pr(5r(t8 S7's
D(3(t >> . ?2erat5r
% D(3(t >%> < STD C5(* B54
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8 = = 6 2 8
ayer2 !AF SN @ !SN !@ @ SGA4E ATA C4C
ayer S@! S@%
SubSerice !ie$d Serice @ndicator
GC %GC 7SE4 GA4T
@S7G 0essa1e Type 0andatory !@H 0andatory &ariab$e %ptiona$ !@H %ptiona$ &ariab$e
@A0 A Garty Cate1ory , !or-ard Ca$$ @ndicator Garty No , 7ser serice @nfo C@ , Carrier , NI , *%Gs
Net-or# @ndicatorNAT"9, @NAT"9
Griority < ,2, o- to *i1h )
s , a:6
Se$ection )Si1na$$in1
in#
C@C on$y@S7G)
" !@S7
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SCCG 0essa1e Type 0andatory !@H 0andatory &ariab$e %ptiona$ !@H %ptiona$ &aria
7T
H7T
7Ts . Se1mentation data
H7Ts . Se1mentation data
. Ca$$ed Garty2. Ca$$in1 Garty. 7ser ata
. Ca$$ed Garty2. Ca$$in1 Garty. 7ser ata
. 4eturn Cause2. *op Counter
. Ca$$ed Garty2. Ca$$in1 Garty. 7ser ata
. 4eturn Cause2. *op Counter
. Ca$$ed Garty2. Ca$$in1 Garty. 7ser ata
Protocol Class %C$ass
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SCCP - Routing Protocol
3o Co)nter 14 to 1 " % Counter is decremented upon FTTSegmentation % 0a: 6 Se1ments , each carries 2/6 bytes
*TT CASES. SGC K SSN2. SGC K SSN K FT. SSN K FT/. SGC K FT5. FT on$y
FT is performed on 1ien SGC K SSN on the basis of FT info , to find outthe fina$ A9 Garty Address
SS- SCCG 0ana1ement @SN user part/ %0AG %peration, 0aintenance and Administration Gart)5 0AG 0obi$e App$ication Gart)6 *4 *ome ocation 4e1ister)= &4 &isitor ocation 4e1ister)8 0SC 0obi$e S-itchin1 center)> E@4 E'uipment @dentifier re1ister)" A7C Authentication Centre) @SN Supp$ementary Serices SSAG) roadband @SN ed1e
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*TT6 0ethod of hidin1 the SS= point code and sub
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T4ANSACT@%N @A%F TAF C%0G%NENT TAF
Message type FunctionIn0o/e @nitiates9ino#es a desired operation at the remote peer app$ication entity.
Ret)rn res)lt not last 7sed to carry a se1ment of the resu$t of a successfu$$y comp$eted operation. @t is used -hen a success rep$y is physica
Ret)rn res)lt last 4epresents the fina$ success rep$y to an operation inocation. @f the success rep$y -as se1mented, this component -o
Ret)rn error @ndicates an operation ino#ed preious$y has fai$ed due to some processin1 error. Error codes are supp$ied by TCAG
Re7ect @ndicates that one of the @no#e, 4eturn 4esu$t, or 4eturn Error components receied from the remote user9CS cou$d
Uni!irectional 7sed to transport data in an unstructured dia$o1ue
Begin !irst messa1e, to start a structured dia$o1ue, sent once
Contin)e 7sed to sustain the structured dia$o1ue, more continue messa1es can be sent
En! 7sed to terminate the structured dia$o1ue in a norma$ -ay
A(ort 7sed to terminate the structured dia$o1ue in an off norma$ -ay.
TCAP :1& Transaction Part % 'eals 8ith SCCP Message " a. TCAG 0essa1e Type ; EF@N 9 7N@ 9 EN 9 C%NT@N7E 9 A%4T b. en1th @ndicatior of Transaction Ta1 0a: 2"/8 , SCCG ta#es Care of Se1mentin1 9 rea#in1 ) c. Transaction @nfo Not &a$id for 7N@ ) i. %ri1ination Transaction @d 0andatory for EF@N , C%NT@N7E )
< en1th @ndicator J &a$ue i. estination Transaction @d 0andatory for EN , A%4T , C%NT@N7E ) < en1th @ndicator J &a$ue i. GMAbort Cause 0andatory for TCMGMAbort 4e'uest ) < 4eason for Abort
2& 'ialog Part % a. ia$o1 @ndicator Ta1 b. en1th @ndicatior of ia$o1 Ta1 c. ia$o1 @nformation < epend on 7SE4 !or E: ; 0AG , @NAG
$& Message Comonent Part % 'eals 8ith USERs s)ch as MAP + I-AP &&&" a. Component @ndicator Ta1 b. en1th @ndicatior of Component Ta1 c.Component Type ; @no#e 9 4eturn 4esu$t ast 9 4eturn 4esu$t Not ast 9 4eturn Error 9 4eect ) d. Component $en1th e. Component 7ser @nformation by 0AG , @NAG , CA0E , %0AG , SSAG Etc..........
5)nctions of TO The transactioO The communic
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SMSC. S0S are stored in S0SC before they can be sent to 0S /" bytes each S0S )2. 0AG 7SE is P !or-ard Short 0essa1e Submit P Send 4outin1 @nfo for S0 P !or-ard Short 0essa1e e$ier
. 0% !or-ard S0 ; A party 0S to S0SC !or-ard Short 0essa1e Submit )/. 0T !or-ard S0 ; S0SC to Garty 0S !or-ard Short 0essa1e e$ier )
*
F0SC
TCAG e1TCAG End 9 4et
S0ME@&E4
TCAG e1in9@no#e < !or-ard S0
TCAG End 9 4etrun 4es < !or-ard S0 A
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SCG
SCG
STG
STG
STG
STG
SSG Serice S-itchin1 Gt )
A