01
IP allow-list
IP authentication instead of credentials: authenticate by source address, for platforms with fixed egress IPs.
Connection details
Applies to
SMPP, HTTP API and SIP
Configuration
Allow-list of your egress addresses
Changes
Handled by the NOC, usually same day
Combined with
Credentials, for defence in depth
02
SIP / RTP
A SIP interconnect for voice termination, Voice OTP and TTS, with an engineer on the call for interop.
Connection details
Signalling
SIP over UDP or TCP
Media
RTP, G.711 A-law / µ-law and G.729
Authentication
Static IP or digest
DTMF
RFC 2833
03
HTTPS / JSON
A straightforward HTTP REST API in JSON, for teams that would rather not run a persistent SMPP session. Same routes, same balance, same receipts.
Connection details
Transport
HTTPS, TLS 1.2 or above
Format
JSON request and response
Authentication
API key, optionally pinned to an IP allow-list
Callbacks
Delivery receipts pushed to your webhook, or polled
04
SMPP v3.4
An SMPP v3.4 bind is the standard way to move A2P SMS at volume. Transmitter, receiver or transceiver, with real end-to-end delivery receipts.
Connection details
Bind types
Transmitter, receiver, transceiver
Encoding
GSM 03.38, UCS-2, concatenated / long SMS
Delivery receipts
End-to-end DLR on the same session
Authentication
System ID, password and IP allow-list