Roaming Principles
Charging
Called Party in Roaming
HLR
SCP
HLR
(iii) PRN, resp
(ii) PRN
(MSRN)
(i) SRI
(iv) SRI, resp
(MSRN)
CAU-B
GMSC
MSC/VLR
0 CSP MSRN*
LDO
MSC/
VLR
A
B is in
roaming
Calling Party Pays
B
Called Party Pays
MSRN*=Mobile Station
Roaming Number
no formato nacional
Roaming Principles
Charging with Call Forwarding
Called Party with Call Forwarding
Service
HLR HLR
SCP
(iii) PRN, resp
(ii) PRN
(MSRN)
(i) SRI
(iv) SRI, resp
(MSRN)
CAU-B
GMSC
MSC/VLR
0 CSP MSRN*
LDO
MSC/
VLR
A
B is in
roaming
0 CSP CAU-C
CFU
Calling Party Pays
B
Called Party Pays
Called Party Pays
0 CSP CAU-C
CFNRc / CFNRy
Called Party Pays
Charging of Call Forwarding
ANATEL Regulation 245, art. 77°
A chamada dirigida a Usuário Visitante será tratada como composta por duas
chamadas para efeito de faturamento.
§ 3º Aplica-se ao disposto neste artigo às chamadas reencaminhadas para
outro Código de Acesso a pedido do Usuário, sendo que nesta hipótese a
segunda chamada tem origem na Área de Registro do Usuário e destino no
Código de Acesso para o qual foi reencaminhada a chamada.
•
•
•
GSM Postpaid
– Optimal Routing at Late Call Forwarding optional feature
TDMA Postpaid
– Already Supported
PrePaid (GSM and TDMA)
– The collect call restrictions for terminating calls in SMP prepaid
subscribers are also applied.
Call Forwarding, National Roaming - 1 of 3
Terminated call reaches the GMSC, CFU active
Campinas (019)
HLR
Rio do Janeiro (021)
Sub X
019 9165 4321
Registered: RJ
CFU: 019 3233 3333
(ii) SRI, resp
(i) SRI
(CFU)
MSC/VLR
019 9165 4321
Long
distance
carrier
GMSC
Coverage Area
POTS
VMS
Office: 019 3233 3333
Signaling
Traffic
Call Forwarding, National Roaming - 2 of 3
Standard way and “trombone”effect, CFNRC active
Campinas (019)
HLR
Sub X
019 9165 4321
Registered: RJ
CFNRC:
019 3233 3333
(iii) PRN, resp
Rio do Janeiro (021)
(ii) PRN
Sub X
019 9165 4321
CFNRC:
019 3233 3333
(MSRN)
(iv) SRI, resp
(i) SRI
(MSRN)
MSC/VLR
No Page
Response
019 9165 4321
Paging
Long
distance
carrier
GMSC
Coverage Area
POTS
VMS
Office: 019 3233 3333
Signaling
Traffic
Call Forwarding, National Roaming - 3 of 3
Optimal Routing on Late Call Forwarding (OR on LCF)
Campinas (019)
HLR
Sub X
019 9165 4321
Registered: RJ
CFNRC: VMS
Rio do Janeiro (021)
Signaling
Traffic
PRN’
Sub X
019 9165 4321
Ericsson
Proprietary
RCH Ack.’
RCH’
019 9165 4321
Long
distance
carrier
GMSC
MSC/VLR
No Page
Response,
Busy or
No Answer
Paging
Coverage Area
POTS
VMS
Office: 019 3233 3333
International Roaming
Terminated call successful
Brazil (55)
HLR
Mexico (52)
Sub X
021 9165 4321
Registered: Mexico
(ii) PRN
(iii) PRN, resp
(i) SRI
(iv) SRI, resp
(MSRN)
(MSRN)
MSC/VLR
021 9165 4321
GMSC
International
Long
distance
carrier
Signaling
Traffic
Roaming and Call Forwarding
Concerns – 1 of 3
• OR on LCF depends on Ericsson nodes at both sides
• Thus not applicable when different Core vendors are involved:
 National Roaming (i.e. TA – Oi)
 International Roaming
• ANATEL Regulation 316, art. 29 and paragraph 6o mentions
explicitly that Voice Mail access shall not be considered as Call
Forwarding. Possible solutions:
 TA pays the Long Distance International leg of the call to VMS
(absolutely not suggested)
 Ericsson optional feature that blocks Call Forwarding services of
the users roaming internationally.
Roaming and Call Forwarding
Concerns – 2 of 3
National Roaming – GSM
Charging ?!
OPERATOR Y
OPERATOR X
Overlapping
Coverage
Roaming and Call Forwarding
Concerns – 3 of 3
OSB – Operator Specific Barring
Blocking outside HLR
• In the GSM standard OSB is not sent outside HPLMN
• In Brazil TIM and Oi sends OSB also to each others and
therefore also to TA!
• Be aware of roaming subscribers and the use of OSB
Category
Use (Mobile Originating)
OSB1
Blocking of Long Distance Calls
OSB2
-
OSB3
-
OSB4
(VPN ATS, by Claro)