UE-A RNS-A VLR-A AUC

Channel resCM service req

Channel req.

Authenticate

CM service ack

VLR-B UE-B

Start security procedures

Cipher mode complete

Complete call

RAB Assignment res

MSC-A HLR MSC-B

Proccess access req Authenticate parameter req Authenticate

info reqAuthenticate info res

Authenticate parameter res

Authenticate res

security control cmd security control res security procedures complete

Accept access req

Cipher mode comand

Set-up SFOC (Send Information for Out-going Call )

Call proccessingRAB Assignment reqAssignment

comandAssignment complete

Send routing information reqProvide MSRN req

Provide MSRN resSend routing information res

ISUP IAM

RNS-B

ACM (Address Complete Message )Alart

Alart

connectAnswer

connectCall service

Call service

Disconnect

Disconnect

ReleaseReleaseRelease complete Release complete

IU release

Channal release IU Release complete

SFIC (Send Information for In-coming Call )

Paging

Paging resProcess access req Connect

confirmProcess access res

Set-up

Assignment res

Assignment req

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