Concatenation
Qué es Concatenation?
Esta entrada está disponible actualmente solo en inglés.
Concatenation is the mechanism that splits an SMS longer than one segment's character limit into linked parts at send time, then reassembles them into one visible message on the recipient's handset. The linkage rides a User Data Header (UDH) inside every part, which is why the per-part budget drops below the single-segment limit. Concatenated SMS and concatenation name the same concept — one describes the message shape, the other the splitting mechanism.
More detail
Encoding still decides the per-part budget: GSM-7 goes from 160 characters single-part to 153 per part under concatenation, and Unicode from 70 to 67. So a 161-character GSM-7 text concatenates into two segments, and each one bills separately — a routed, sequenced chain rather than one longer message.
Orbit computes the concatenated segment count per outbound message at the API layer, so the predicted cost is visible before send — the related encoding terms (GSM-7, Unicode) and the segment concept below carry the mechanics that drive the count.
Preguntas frecuentes
- Why does a concatenated message bill as multiple SMS segments?
- Because the network treats each linked part as its own transmission unit and bills it separately — the concatenation header (UDH chains the parts) just keeps the split reversible on the handset. GSM-7 and Unicode budgets still apply per part.
- Is concatenation the same as concatenated SMS?
- Yes — concatenation is the mechanism; a concatenated SMS is what any message over one segment's limit becomes. The two terms describe the same split-and-reassemble behavior.
See also
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