Global connectivity — specifications
Connectivity on our own MVNO and partner networks, for enterprises, providers and operators.
- Sponsored roaming
- Data, voice and SMS on our MVNO
- DID numbers worldwide
- Calls and SMS over SIP, SMPP, SS7, IPX/GRX
STL-CON-01 · SIP · SMPP · SS7 · IPX/GRX
Voice, SMS and signalling interconnect
SILTATEL exchanges calls, SMS and roaming traffic with carriers, aggregators and partner networks over standard interconnects — each partner connects over the interface it already runs.
Notes
- Voice: SIP (RFC 3261) with RTP media (RFC 3550); SIP-I (ITU-T Q.1912.5) where ISUP information must pass end to end.
- SMS: SMPP v3.4 / v5.0 binds to aggregators and SMSCs; MAP MO/MT-ForwardSM on the SS7 side (3GPP TS 29.002).
- SS7 over IP: SIGTRAN — M3UA (RFC 4666) over SCTP (RFC 9260); call control with ISUP (ITU-T Q.761–Q.764).
- Data roaming: GTP (3GPP TS 29.274, 29.281) and Diameter S6a (3GPP TS 29.272) across IPX/GRX (GSMA IR.34); LTE roaming per GSMA IR.88.
- Numbers: E.164 ranges, including DID numbers for inbound calls and SMS.
Standards and references
| Body | Document | Title |
|---|---|---|
| IETF | RFC 3261 | SIP: Session Initiation Protocol |
| IETF | RFC 3550 | RTP |
| ITU-T | Q.1912.5 | Interworking SIP – BICC/ISUP (SIP-I) |
| SMS Forum | SMPP v3.4 / v5.0 | Short Message Peer-to-Peer protocol |
| 3GPP | TS 29.002 | Mobile Application Part (MAP) |
| IETF | RFC 4666 | SS7 MTP3 User Adaptation Layer (M3UA) |
| IETF | RFC 9260 | Stream Control Transmission Protocol (SCTP) |
| ITU-T | Q.761–Q.764 | ISDN User Part (ISUP) |
| 3GPP | TS 29.272 | Diameter S6a/S6d |
| 3GPP | TS 29.274 · 29.281 | GTPv2-C · GTP-U |
| GSMA | IR.34 | Guidelines for IPX Provider networks |
| GSMA | IR.88 | LTE and EPC Roaming Guidelines |
| GSMA | IR.92 | IMS Profile for Voice and SMS (VoLTE) |
STL-CON-02 · GSMA IR.21 · IR.73 · TD.57
Sponsored roaming
With sponsored roaming a subscription uses the roaming agreements of a sponsor network. The SIM carries the sponsor's IMSI, so visited networks treat the device as the sponsor's roamer — while service, tariffs and the customer relationship stay with SILTATEL.
Notes
- Network data of roaming partners is exchanged in GSMA IR.21 records; visited networks route signalling to the sponsor's HLR/HSS.
- Steering of roaming (GSMA IR.73) lets the sponsor prefer selected networks in each country.
- Visited networks charge the sponsor with TAP records (GSMA TD.57); the sponsor bills SILTATEL wholesale.
- A multi-IMSI applet can switch between sponsors by region — managed over the air (see the eSIM sheets).
Questions
What is sponsored roaming?
Access to networks abroad through another operator's (the sponsor's) roaming agreements: the device roams with the sponsor's IMSI, and the service provider buys that access wholesale.
Why not sign own roaming agreements?
Bilateral agreements with every network take years to sign and test. A sponsor gives its whole footprint at once; own agreements can be added later where volumes justify them.
What is a DID number?
Direct Inward Dialling: an E.164 number that routes calls or SMS straight to a customer's system — a PBX, contact centre or application — over SIP or SMPP.
How is an SMS delivered worldwide?
Over SMPP to an aggregator or SMSC, or over SS7 MAP directly to the destination network; the route is chosen per destination for quality and cost.
Glossary
- HPMN / VPMN
- Home and visited public mobile networks.
- IPX
- IP eXchange: the GSMA inter-operator IP backbone (IR.34).
- GRX
- GPRS Roaming eXchange: the predecessor of IPX for data roaming.
- TAP
- Transferred Account Procedure: roaming charging records.
- SIGTRAN
- SS7 signalling carried over IP.
- DID
- Direct Inward Dialling number.
Standards and references
| Body | Document | Title |
|---|---|---|
| GSMA | IR.21 | Roaming Database, Structure and Updating Procedures |
| GSMA | IR.73 | Steering of Roaming Implementation Guidelines |
| GSMA | TD.57 | Transferred Account Procedure (TAP3) |
| GSMA | IR.34 | Guidelines for IPX Provider networks |