Sender Pool
What is Sender Pool?
A sender pool is the set of outbound senders — long codes, short codes, alphanumeric sender IDs, or WhatsApp numbers — a message draws its routing identity from when it is sent. A send walks the pool's senders in rotation, applying per-sender throughput caps and per-country eligibility, so one degraded sender shifts traffic to the rest instead of stalling messages.
More detail
On Orbit a send resolves its sender through the chain `from → sender_pool_id → messaging_service_id`: a direct sender wins, a named pool picks from its members, and a messaging service fills in only when neither is passed.
When every sender in a pool is over its throughput cap or removed, message rows sit at pending until capacity returns — the fix is to add senders or route through a pool with free capacity, not to resubmit the batch.
Pool size is a tenant-owned control: a pool spread thin across many lightly-used numbers reads as snowshoe spamming to carriers, which flag the pattern at the pool level. Orbit flags an over-spread pool as needing consolidation, and sizing the pool to real send volume avoids the reading.
Frequently asked
- What happens when my pool is empty?
- Message rows stay at pending until a sender is added back or free capacity returns — add senders to the pool or route through another pool with capacity, and the queued messages draw from the new sender. See the sender-pool-empty troubleshooting page.
- How does Orbit prevent snowshoe?
- Carriers flag thin, oversized pools as snowshoe at the pool level, not one number at a time. Orbit's deliverability autopilot watches pool shape and flags an over-spread pool for consolidation, so pool size tracks real send volume instead of dodging per-number thresholds.
- Which resolution wins: from, sender_pool_id, or messaging_service_id?
- The chain checks from first, then sender_pool_id, then messaging_service_id — a direct sender named on the message wins, and a messaging service fills in a sender only when neither a direct sender nor a pool was passed.
See also
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