What are the issues with relying on handset delivery receipts?

Question

What are the issues with relying on handset delivery receipts?

Applies To

• Delivery Receipts (DLR)
• Outbound SMS

Answer

Handset delivery receipts are one measure of performance but it is not a perfect one. For several reasons:

• Carriers will most likely prioritize outbound traffic over handset delivery notification.
• The handset processing the message adds an extra latency to the delivery receipt path.
• When absent subscriber, no handset delivery receipt is provided in most cases until the phone is connected to the network again.

In order to measure the success of our delivery we use a number of sources, of which DLRs are just one of many.