Vonage supports Domestic and International enterprises SMS business to India.
To follow the regulations of Telecom Regulatory Authority of India (TRAI), domestic enterprises can only submit A2P SMS through domestic connections to the end recipients after successful registration with Distributed Ledger Technology (DLT).
DLT aims to create a cleaner and transparent system in the Indian telecom industry and curb Unsolicited Commercial Communication (UCC) and an enhanced mobile subscriber policy. The new regulation can be accessed here.
Any enterprise that fails to pre-register Distributed Ledger Technology (DLT) will become non-compliant and will not be able to send A2P SMS to the end recipient via domestic connections.
Please notice International Enterprises are not affected by this change.
Timeline information of the DLT implementation
Phase 1 - SenderID/Header Scrubbing
- Live since 1 June 2020
- Only DLT registered SenderIDs can terminate SMS on domestic routes.
- Entity Registration and Header Registration mandatory.
Phase 2 - PEID/Entity Unique ID Scrubbing
- Live since 19 November 2020
- PE ID is mandatory to provide along with the Header for successful SMS termination.
- Entities have to start registering their Content and Consent Templates on the DLT Portal on which they have registered their entities.
Phase 3 - Template/Content Scrubbing
- Live since 1 April 2021
- Only DLT registered Templates, along with SenderID & PEID able to terminate SMS on domestic routes.
- Similar to the Sender ID upload process, you need to upload these templates with any one operator DLT portal.
- In place since 22 April 2021
- Brand Name is mandatory to be included in the template registration content
Complying with DLT and Vonage
- It is mandatory to have a brand name in all categories of messages
- The exact text should match from your application to suppliers to the DLT Platform
- Only Approved Templates should be submitted/uploaded to the Vonage.
- Header Mapping against each template should be verified.
- Where header ‘X’ is mapped on the DLT platform with a ‘Y’ text, then it should be used accordingly.
- If you wish to use any other header, Changes on the DLT platform should be done accordingly.
- The variable length should not exceed 30 characters
- 30 characters per variable including the spaces and the content templates can be registered with variables in GSM (English) characters and in unicode (for local dialect characters)
- If it is more than 30, you will need to add more variables
Registering for DLT
To send any SMS through domestic connections, all enterprises must register their Principal Entity, Headers, Templates with the Brand Name & provide consent on one of the approved DLT systems:
Maintaining compliance while submitting your messages to the Vonage platform
Once you have registered for DLT with one of the portals there are two ways to ensure your traffic is compliant with DLT.
Please notice Vonage is not responsible for domestic entities registering for DLT. We do not verify if domestic entities have correctly provided their PEID, senderID and templateIDs.
Option 1: Submit the required DLT parameters with every request
- Make the necessary changes at your end so that your Entity ID, Sender ID/Header and Templates (as registered with DLT) are sent/used with every API submission (see additional properties you must use below)
- Inform Vonage via email@example.com to enable routing for option 1 for you SenderID
- Start sending SMS once you have received confirmation routing has been enabled for you
Option 2: Let Vonage detect your template
- Create your DLT Details csv file
- Download the template file from your DLT Portal
- Add your details to this file
- Save as <entityid>.csv where <entityid> is your EntityID
- Your PEID - Entity unique ID received from DLT after Entity registration Approved
- Entity Name - The company name registered on DLT
- Sender Name - The six character alphanumeric Sender/Header, which has been registered and approved in DLT
- The name of which DLT system you are registered on
- Your DLT details file (File mentioned above)
Additional Parameter/Properties To Support DLT
Vonage has added functionality within our Send SMS API endpoint or via SMPP to allow domestic entities to comply with the DLT regulation by providing both their PEID (unique entity ID) and the template ID for every SMS request made.
The API properties used in this endpoint are to be matched exactly as listed below:
- ‘entity-id’ parameter needs to be the DLT approved PEID (unique Entity ID)
- ‘content-id’ parameter needs to be the DLT approved Template ID
- ‘from’ parameter needs to be the DLT approved Sender ID (Header ID)
- If you use SMPP to send SMS messages with Vonage, the following fields apply:
- 0x1470 needs to be the DLT approved PEID (unique Entity ID)
- 0x1471 needs to be the DLT approved Template ID
- The Sender ID needs to be the DLT approved Sender ID (Header ID)
Vonage Error Codes for DLT related issues
|50||DLT entity ID details are missing or wrong (includes null + invalid value)|
|51||DLT header ID (Sender ID) details are missing or wrong (the Sender IDs must be registered with suppliers but not with DLT platform)|
|52||DLT content ID details are missing or wrong|
|53||DLT error for consent|
|54||DLT generic error|
By default, customers will fall into the International promotional(SMS without opt in) category with restrictions as mentioned below.
If you are an Int'l customer or have different SMS type other than as listed below, please contact your account manager or email firstname.lastname@example.org.
|Traffic Type||Content Allowed||Sender ID||Restrictions/Regulation|
|Domestic Transactional||Transactional traffic, OTP||6 digit alpha with DLT pre-registration||No restrictions. 24/7 delivery without NDNC restrictions.
The registered Alpha Sender ID will be added with 2 letters as a prefix, depending on which carrier was used to deliver the SMS to the final operator or 2 random numbers; e.g., MD-XXXXXX (where XXXXXX is the registered Sender ID)
|6 digit numeric with DLT pre-registration||
Promo SMS will be blocked to numbers registered in NDNC as per TRAI regulation.
DLR not supported started since 9 Oct 2020
|International (transactional/Opted-in Promo)||
International originated transactional content & Opt-in Promo content.
(If the client registered in India, but the SMS message originated from outside India, it will be identified as International traffic).
|Sender ID not supported and will be changed to a random short/long virtual number||
For OTP/Transactional traffic mainly. For Opted-in promo, content needs whitelisting through your Account Manager before sending SMS.
SMS Delivered 24/7 via International route.
|International Promotional (without opt-in) Default route||Promo/Marketing content||Sender ID not supported and will be changed to a random short/long virtual number||
Delivery on best effort basis with shared SC from SMS partner.
10am-9pm(IST) delivery to non-NDNC customers only
For enterprises that finished the DLT application successfully, the SMS Sender ID will be prefixed with an additional 2 letters, depending on which final operator the number belongs to. A full list of prefixes can be found here: India Pre-registered SenderID Prefixes
Alpha Sender ID is not supported for International customers and will be changed to a random shortcode.
Please note that it is possible to also complete the registration of Alpha Sender IDs to other countries.
Please get in touch with your Account Manager to discuss processing Sender ID registration If you have more than 1 million messages a month.
Do Not Call Registry/Do Not Disturb Service
Promotional SMS are barred and will get blocked by operators to numbers those registered in the Indian NDNC (National Do Not Call registry).
SMS delivery is blocked between 21:00 – 10:00 hrs IST for end recipients who registered with Do Not Disturb Service (DND). This means promotional SMS can only be delivered only between 10:00 - 21:00 hrs IST.
Operators do not support delivery notifications for messages sent via Promotional routes with numeric headers.
Limitation to avoid potential SMS flooding
Local regulations specify limitations to the number of messages that can be sent to the same number:
- More than 6 messages to the same destination number within an hour with the same sender or text may be blocked.
- Users may not receive more than a total of 200 SMS per day across all incoming streams.
Unicode is supported.
- Transactional/OTP Traffic: DLR is supported and its reliable delivery receipts.
- Promotional Traffic: DLR is not supported. And/Or it's unreliable Network DR.
Traffic restriction by political reason
Messages towards Jammu and Kashmir networks (example, 405/55 - Airtel J&K) will be blocked by the government due to political sensitivity.
Please also note that political SMS is prohibited throughout the country during an election period.