Guides

SMPP & SMS testing guides

Practical articles for developers and QA engineers who test SMS applications, SMPP clients and delivery flows.

Nov 2, 2026 · 6 min read

Multipart (Concatenated) SMS over SMPP: UDH, SAR and Limits

Why a long SMS becomes several parts, how UDH and SAR concatenation work, and what to test in your client.

Nov 2, 2026 · 5 min read

Failure handling is the part of SMS software that is hardest to test against a real provider. Here is how to make it repeatable.

Nov 2, 2026 · 6 min read

The SMPP v3.4 command_status codes you will meet in practice, which ones are worth retrying, and how to make your client handle them.

Nov 2, 2026 · 6 min read

A practical setup for running SMS and SMPP tests on every commit, with no real traffic and no flaky results.

Nov 2, 2026 · 6 min read

The cases your OTP and 2FA code must survive, and how to reproduce each one safely with a sandbox.

Sep 24, 2026 · 5 min read

A practical guide to the three SMPP bind types, the PDUs each one allows, and how to choose between TX, RX and TRX connections.

Sep 24, 2026 · 6 min read

How SMPP delivery receipts (DLRs) are built, what each stat value means and how to test every outcome with an SMSC simulator.

Sep 24, 2026 · 5 min read

What an SMPP test tool is, what to check when testing an SMPP client, and how an SMSC simulator lets you do it without paying for real SMS delivery.

Sep 24, 2026 · 5 min read

What SMS simulation is, when an online SMS simulator saves time and money, and what a good simulator should let you control.

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