sms home routing

© 2007 GSM AssociationNotice: All GSM Association meetings are conducted in full compliance with the GSM Association’s antitrust policy

SMS Home Routing

- Bilateral case

Restricted to: Full & Associate Members

For Approval / Information / Discussion:

For Information

Version 1.0

IWG Doc 06_069

IWG#6 meeting in Montreal, 7 May 2007

Axel Doerner, Vodafone D2

08/04/23 © 2007 Copyright GSM AssociationRESTRICTED

2

Aim of this presentation

• Explain what SMS Home Routing is and identify impacts

• Present the current status of the discussion and next steps


3

SMS Interworking – normal flow in case of roaming

Home A (APMN) Home B

Visited B

SMSCSMSC HLRHLR

submit

Obtain routing info

forward

deliver

User A

User B

• Existing Interworking Agreements explicitly exclude this scenario, although in principle this scenario could be included into the interworking agreement (“Scenario 5” in AA.19/BA.43)1

• Side effect noted: By default SMS delivery will only work if Home A has a signalling agreement with Visited B. Where no roaming/interworking agreement is in place between Home A and Visited B it is therefore not guaranteed that the SMS can be delivered!

• Existing Interworking Agreements explicitly exclude this scenario, although in principle this scenario could be included into the interworking agreement (“Scenario 5” in AA.19/BA.43)1

• Side effect noted: By default SMS delivery will only work if Home A has a signalling agreement with Visited B. Where no roaming/interworking agreement is in place between Home A and Visited B it is therefore not guaranteed that the SMS can be delivered!

V-MSCV-SGSNV-MSCV-SGSN

1See backup slide on the complexity of billing for scenario 5 1See backup slide on the complexity of billing for scenario 5


4

SMS Interworking – flow in case of home routing

Home B

Visited B

SMSCSMSC

V-MSCV-SGSNV-MSCV-SGSN

HLRHLR

submit

Obtain routing info

forward

deliver

User A

User B

• Some networks have implemented “Home Routing” for SMS-MT (tbc)

• Instead of returning the actual address of the recipient user Home B returns the address of an SMS Router operated by Home B which in turn forwards the message to the user

• The SMS Router functionality is standardised by 3GPP in R7 (see TR 23.840, TS 23.0401)

• Some networks have implemented “Home Routing” for SMS-MT (tbc)

• Instead of returning the actual address of the recipient user Home B returns the address of an SMS Router operated by Home B which in turn forwards the message to the user

• The SMS Router functionality is standardised by 3GPP in R7 (see TR 23.840, TS 23.0401)

SMS RouterSMS Router

forward’

C:\Work\Standards\3GPP\23840-710.zip

1This is the SMS stage 2 spec, not included here but available from ftp.3gpp.org/specs/latest/Rel-7/23_series for download 1This is the SMS stage 2 spec, not included here but available from ftp.3gpp.org/specs/latest/Rel-7/23_series for download

Note: Internal signalling flow in Home B not shown here for sake of simplicity

Note: Internal signalling flow in Home B not shown here for sake of simplicity

Home A (APMN)


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Impacts of SMS home routing

Potential Benefits• May fix some “strange” effects that some short messages do not reach the recipient

although SMS interworking is in place• Allows Home B to implement additional services, e.g.

– persistent SMS storage on a network server, SMS redirection, better Spam Control • Aligns SMS with the common architecture for all other types of messaging services (IM,

MMS, Email)– may allow to achieve co-hosting synergies (e.g. implement MMS and SMS on a

single platform)

Potential Downsides• Loss of transparency for Home A

– Home A will not know whether the recipient was roaming and will also not definitely know whether or not the SM was delivered

– On the other hand Home B has better means to preserve the privacy of the recipient user

• Could “silently” extend the SMS Interworking agreement between Home A and Home B to scenario 5.

– Home A will have to pay also termination charges for short messages sent to roaming subscribers to Home B

– Need to re-negotiate (extend) existing SMS interworking agreements?


6

Impacts of SMS home routing

• May fix some “strange” effects that some short messages do not reach the recipient although SMS interworking is in place

• Allows Home B to implement additional services, e.g.

– persistent SMS storage on a network server, SMS redirection, better Spam Control

• Aligns SMS with the common architecture for all other types of messaging services (IM, MMS, Email)

– may allow to achieve co-hosting synergies (e.g. implement MMS and SMS on a single platform)

• May fix some “strange” effects that some short messages do not reach the recipient although SMS interworking is in place

• Allows Home B to implement additional services, e.g.

– persistent SMS storage on a network server, SMS redirection, better Spam Control

• Aligns SMS with the common architecture for all other types of messaging services (IM, MMS, Email)

– may allow to achieve co-hosting synergies (e.g. implement MMS and SMS on a single platform)

Potential BenefitsPotential Benefits• Loss of transparency for Home A (APMN)• Home A will not know whether the recipient

was roaming and will also not definitely know whether or not the SM was delivered

• On the other hand Home B has better means to preserve the privacy of the recipient user


• Home A will have to pay also termination charges for short messages sent to roaming subscribers to Home B

• Need to re-negotiate (extend) existing SMS interworking agreements?

• Loss of transparency for Home A (APMN)• Home A will not know whether the recipient

was roaming and will also not definitely know whether or not the SM was delivered

• On the other hand Home B has better means to preserve the privacy of the recipient user


• Home A will have to pay also termination charges for short messages sent to roaming subscribers to Home B

• Need to re-negotiate (extend) existing SMS interworking agreements?

Potential DownsidesPotential Downsides


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The issue – zoomed-in in greater detail

What it‘s not• SMS Home routing is not a matter of charging principles – BA.27 explicitly allows (and

always has allowed) to raise termination charges for SMs sent to roamers

What it is• SMS Home Routing is a matter for signed AA.19s and the standard scope of an AA.19

based interworking agreement (“Scenario 1”) which explicitly excludes the roaming case irrespective of the actual routing of the SMS

• One primary reason why the roaming scenario is excluded from the existing agreements is the complexity of corresponding Billing processes

"Scenario 1 (Detailed in Annex 1) SMS sent from an APMN Operator and transferred to a Customer of an HPMN Operator when the Customer of the HPMN Operator is located on the network of the HPMN Operator (HPMN Operator charges the APMN Operator for SMS MT not “reverse charged”). […]Scenario 5SMS sent from the APMN Operator to Customers of the HPMN Operator roaming on a third party PMN network. As international roaming SMS traffic, this scenario is governed by the existing PRDs of BARG and the relevant charging principles of the International GSM roaming arrangements between the parties involved.“

"Scenario 1 (Detailed in Annex 1) SMS sent from an APMN Operator and transferred to a Customer of an HPMN Operator when the Customer of the HPMN Operator is located on the network of the HPMN Operator (HPMN Operator charges the APMN Operator for SMS MT not “reverse charged”). […]Scenario 5SMS sent from the APMN Operator to Customers of the HPMN Operator roaming on a third party PMN network. As international roaming SMS traffic, this scenario is governed by the existing PRDs of BARG and the relevant charging principles of the International GSM roaming arrangements between the parties involved.“

Scenario descriptions (quoted from AA.19)Scenario descriptions (quoted from AA.19)


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Additional considerations

• Realistically it will not be possible to prevent Home Operators from implementing the SMS Home Routing Option …

• …. as there are a number of advantages for the SMS service as such which cannot be achieved with the traditional architecture

• Accordingly we need to accept that this solution is in the marketplace

• It is not clear how many operators have already implemented Home Routing or are planning to do so

• Accordingly it is unclear whether the impacts on wholesale revenue streams will be considerable or neglectable


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Ad hoc recommendation to IWG members

• For new SMS interworking agreements check carefully whether the standard scenario description from AA.19 meets your requirements

• Have you or your interworking partner (where acting as Home Operator) already Home Routing in place …

• … or are there intentions to introduce it?

• Then you may want to adjust the scenario description in AA.19 according to your needs (i.e. “include scenario 5” into the scope)

• For new SMS interworking agreements check carefully whether the standard scenario description from AA.19 meets your requirements

• Have you or your interworking partner (where acting as Home Operator) already Home Routing in place …

• … or are there intentions to introduce it?

• Then you may want to adjust the scenario description in AA.19 according to your needs (i.e. “include scenario 5” into the scope)

New SMS Interworking agreements New SMS Interworking agreements • Home operators who have implemented SMS

home routing and have used the standard AA.19 scenario description could be challenged by their interworking partners as they have silently extended the scope of their interworking agreement (“charge for more than was agreed”)

– These operators are urged to notify the use of Home Routing to their Interworking partners and to re-negotiate their existing agreements accordingly

• It was reported that in some cases Home Operators who have implemented SMS Home Routing do not charge the APMN for messages sent to roamers

– In this case the Home Operator formally complies with the standard AA.19, the APMN operator will not be able to reconcile the invoice properly, though.

• Home operators who have implemented SMS home routing and have used the standard AA.19 scenario description could be challenged by their interworking partners as they have silently extended the scope of their interworking agreement (“charge for more than was agreed”)

– These operators are urged to notify the use of Home Routing to their Interworking partners and to re-negotiate their existing agreements accordingly

• It was reported that in some cases Home Operators who have implemented SMS Home Routing do not charge the APMN for messages sent to roamers

– In this case the Home Operator formally complies with the standard AA.19, the APMN operator will not be able to reconcile the invoice properly, though.

Ideally, Home Routing should only be switched on for an Interworking

relationship after the interworking agreement has been updated Ideally, Home Routing should only be switched on for an Interworking

relationship after the interworking agreement has been updated

Existing SMS Interworking agreements Existing SMS Interworking agreements


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Forthcoming activities

• Assess and discuss the need for an update of to AA.19

• Look at Home Routing in the context of SMS Hubbing– at first sight it seems that there are no impacts

• Check on the need for standardised technical options which allow to switch on/off SMS Home Routing on a per APMN basis


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Thanks for your attention!

Any Questions?!

[email protected]+491735277885


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Backup


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Billing for SMS Interworking scenario 5 – Illustration of complexity of a TAP based cascading billing approach

VPMNVPMN HPMNHPMN APMNAPMNTAP SMS-MT

recordsBulk Charges?

Summary records?Detail records?

• The Home network would need to analyse the incoming TAP3 SMS MT records and to identify chargeable interworking events based upon the SMSC address which in turn would identify the APMN

• TAP records however could be late and therefore proper collection of all records which are relevant for a given invoice can be difficult.

• Unfortunately neither the transfer of (normally zero charged) SMS-MT records as such nor the correct population of the SMSC address is reliable/enforceable

• The Home network would need to analyse the incoming TAP3 SMS MT records and to identify chargeable interworking events based upon the SMSC address which in turn would identify the APMN

• TAP records however could be late and therefore proper collection of all records which are relevant for a given invoice can be difficult.

• Unfortunately neither the transfer of (normally zero charged) SMS-MT records as such nor the correct population of the SMSC address is reliable/enforceable

• Typically the interworking bill issued by HPMN will not cover exactly all SMS MTs received during the billing interval

• In order to make the Interworking bill reconcilable the APMN will need detail information on what is actually covered by the bill

• This could be summary records on a daily/per VPMN basis but potentially even detail records are needed.

• Typically the interworking bill issued by HPMN will not cover exactly all SMS MTs received during the billing interval

• In order to make the Interworking bill reconcilable the APMN will need detail information on what is actually covered by the bill

• This could be summary records on a daily/per VPMN basis but potentially even detail records are needed.

Zoom in – what would need to be doneZoom in – what would need to be done Impacts

Adds significant complexity which would make the overall SMS interworking billing much more fragile, instable and expensive!The added complexity is one reason why scenario 5 has deliberately been excluded from AA.19

Adds significant complexity which would make the overall SMS interworking billing much more fragile, instable and expensive!The added complexity is one reason why scenario 5 has deliberately been excluded from AA.19

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