Best practices for SMS carriers
SMS Traffic Classification
Skywards presents a technical overview of common A2P traffic types and provides advice on traffic optimization.
In the world of SMS messaging, legal A2P traffic can be classified into 4 distinct types: OTP, transactional, marketing, and gambling. Each with unique characteristics that are crucial to understand not only for optimal routing but also for detecting fraud, as it often blends in with legitimate messages.
What is A2P traffic?
A2P (Application-to-Person) traffic refers to messages sent from a business application or automated system to a mobile user. Instead of manually sending texts, businesses use software to send large volumes of SMS messages, communicating important or targeted information effectively and automatically.
A2P traffic is used for verifications or promotional communications such as appointment reminders, order confirmations, loyalty program updates, customer surveys or security alerts.
A2P traffic is used for verifications or promotional communications such as appointment reminders, order confirmations, loyalty program updates, customer surveys or security alerts.
A2P Traffic Types
TYPE 1
One-Time Password (OTP)
One-Time Passwords are requested by users to verify identity and log in to accounts or confirm transactions. For most aggregators, it generates key revenue due to growing online services and widespread two-factor authentication.
Traffic Specifics
- Types of OTP
Typically it is a small message containing a code in a form of:
1) Numeric code - contains only numbers;
2) Alphanumeric code - uses letters of the alphabet and numbers;
3) Magic link - it is a unique token embedded within a URL link.
1) Numeric code - contains only numbers;
2) Alphanumeric code - uses letters of the alphabet and numbers;
3) Magic link - it is a unique token embedded within a URL link.
- High conversion rate
An additional quality indicator of a route which demonstrates that users are reliably receiving OTPs, entering them successfully, and completing the intended process without friction. Since OTPs are requested and used by the user, this indicator should be as high as possible.
- Disguise for AIT
AIT can disguise itself as a flow of OTP requests, posing a serious threat to A2P providers. Recognizing patterns of generated traffic requires constant monitoring to prevent it from spreading.
Message examples
- Numeric code: Your verification code is 448912
- Alphanumeric code: Your login code is a7Bh2z9
- Magic link: Tap on the link to log in to your account secure-link.com/xyz789
Routing Specifics
OTP is routed through secure, high-priority, low-latency routes to ensure fast delivery due to messages containing critical user information and having a limited lifespan.
Direct connections with MNOs are a reliable but expensive way to deliver OTP messages. A cheaper alternative can be Over the Top (OTT) routes where the end-user receives the message through messenger apps (WhatsApp, Telegram, Viber, etc.). The downsides of these routes would be the need for Internet connection and installed app.
OTP is routed through secure, high-priority, low-latency routes to ensure fast delivery due to messages containing critical user information and having a limited lifespan.
Direct connections with MNOs are a reliable but expensive way to deliver OTP messages. A cheaper alternative can be Over the Top (OTT) routes where the end-user receives the message through messenger apps (WhatsApp, Telegram, Viber, etc.). The downsides of these routes would be the need for Internet connection and installed app.
TYPE 2
Transactional
Transactional messages contain critical and expected information about a user's account or transaction (e.g., shipping confirmations, financial operations, security alerts). The focus here is on utility and trust.
Traffic Specifics
- Content Scrutiny
The message must stay purely informational, as any promotional language could result in it being classified as marketing, a distinct type which has its own regulations and fees.
- Message integrity
As transactional traffic contains important information, no parts of the message, like Sender ID or content, should be changed as it can raise the user's suspicion.
- Used for spoofing
Fraud traffic may impersonate trusted organizations to deceive recipients into revealing personal data.
Message examples
- Payment confirmation message: Your payment #5629 of $150 has been successfully processed. Thank you for using our service. For any questions, please contact support at 123-456-7890.
- Shipment details: Your order 79535 has been shipped and is on its way! Expected delivery is on October 20, 2025. Track your package here: track-link.xyz/543asda43f
Routing Specifics
Transactional traffic demands reliable and consistent delivery routes that maintain low latency to ensure messages reach users promptly.
Although this type of traffic may not be as time-sensitive as OTP, any delays or delivery failures can significantly impact user trust and satisfaction. To maintain message integrity, it is preferable to route such transactional traffic using direct connections and avoid any gray routes as they are prone to modify SMS text or Sender ID.
Therefore, maintaining smooth and timely message transmission is essential to uphold the credibility of the service and prevent negative user experiences.
Transactional traffic demands reliable and consistent delivery routes that maintain low latency to ensure messages reach users promptly.
Although this type of traffic may not be as time-sensitive as OTP, any delays or delivery failures can significantly impact user trust and satisfaction. To maintain message integrity, it is preferable to route such transactional traffic using direct connections and avoid any gray routes as they are prone to modify SMS text or Sender ID.
Therefore, maintaining smooth and timely message transmission is essential to uphold the credibility of the service and prevent negative user experiences.
TYPE 3
Marketing
Marketing messages are used for bulk campaigns to promote products, services, or events. It is characterized by high-volume, bursty traffic aimed at a broad, opted-in audience.
Traffic Specifics
- Call-to-Action
Messages include action words that prompt subscribers to take specific steps and a telephone number or link that they can use to learn more about the products.
- Consent of the recipient
This traffic needs to comply with the electronic marketing rules (e.g., GDPR, PECR) as well as data protection laws, where relevant. This typically requires an affirmative consent from the recipient and a clear unsubscribe mechanism.
- AIT risk
Being a high-volume traffic, it is vulnerable to being flagged by carriers as AIT.
Message examples
- Typical marketing message: Get 20% off on all electronics this weekend only! Shop now and enjoy exclusive deals. Visit our website or your nearest store today. Don’t miss out! Send STOP to unsubscribe.
- Shipment details: TODAY IS THE DAY! Get 70% off on any product with the promo code: DAY70. Shop now: promolink.xyz/sale-today
Routing Specifics
Effective handling of large campaign bursts demands a highly scalable infrastructure that can provide sufficient throughput to support traffic loads without interruption and ensure smooth, continuous delivery.
Effective handling of large campaign bursts demands a highly scalable infrastructure that can provide sufficient throughput to support traffic loads without interruption and ensure smooth, continuous delivery.
TYPE 4
Gambling
Gambling traffic is used to send real-time odds updates, betting confirmations, casino promotions and special offers to users of online gambling platforms. Additionally, it can be account updates such as deposit confirmations, withdrawal notifications, and security alerts.
Traffic Specifics
- Gambling terminology
Messages include specific words or terms that are common in this industry (e.g. casino, betting, game, win, spins).
- Compliance with local regulation
Gambling traffic is typically not considered fraudulent, but many countries have strict laws governing it.
- High risk
Violating local regulation imposes fines or other penalties on MNOs and providers, which can lead to route blockings.
Message examples
- Gambling promotion: Enjoy the sunny weather with a lucky spin! Relax outdoors and try your chance on the reels for a big win! Get free spins using promo code: LUCKY10
- Casino special offer: This is your lucky chance! Grab Mega Spins at a discount: Special Spin for just $30, Fortune Spin only $50. Don't miss out!
Routing Specifics
Aggregators must comply with the specific gambling regulations that vary from country to country.
Each region has its own legal requirements, restrictions, and standards, making it difficult for providers to ensure that traffic is routed in compliance with all applicable regulations.
This can include laws only permitting senders with a valid gambling license in the specific jurisdiction to send gambling traffic. Also, certain types of gambling could be prohibited in specific regions, like sports betting messages are prohibited in most U.S. states.
Aggregators must comply with the specific gambling regulations that vary from country to country.
Each region has its own legal requirements, restrictions, and standards, making it difficult for providers to ensure that traffic is routed in compliance with all applicable regulations.
This can include laws only permitting senders with a valid gambling license in the specific jurisdiction to send gambling traffic. Also, certain types of gambling could be prohibited in specific regions, like sports betting messages are prohibited in most U.S. states.
Skyward SMS Antifraud (SSA)
Skyward SMS Antifraud (SSA) is a cloud-based solution that helps A2P SMS providers protect their valuable routes by checking all SMS messages instantly and automatically blocking any suspicious traffic.
Artificial Traffic Detector (ATD)
Artificial Traffic Detector (ATD) is a solution designed to identify and block SMS AIT fraud, preventing its spread. By analyzing statistical data and traffic flow patterns, ATD quickly detects suspicious activity and stops fraudulent campaigns.
Learn about our solutions
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