SMS Explained

Connecting your system with MailBIT User Friendly SMS API is Easy as 1-2-3 !


  • What is SMS ?
    An SMS, or short messaging service is a type of communication used in mobile phones. They are more commonly called 'text messages'.
  • What is A2P (Application-to-Person) SMS Messaging ?
    The process of sending mobile messages from an application to a mobile user.
  • What is a Sender ID ?
    Sender ID is what appears on SMS recievers phones to show who the SMS is from. With MailBIT this is usually defined by the &sid= parameter in your API request.
    - Fully Dynamic - You can define your Sender ID as you wish, with the only restrictions being length and needing to use characters from the range (0-9, a-z, A-Z, _) Characters outside this range (e.g. ) may or may not be supported depending on the destination operator.
    - Dynamic alpha - You can set any SenderID you like up from a minimum of 4 to maximum 11 characters as long as it only uses letters. Keep in mind that Alpha SIDs can only be used for one-way messages. Since the Alpha SID is not a phone number, it cannot receive replies.
    - Dynamic numeric - You can set any SenderID you like up to 15 digits as long as it only uses numbers
    - Random Numeric - MailBIT will apply a random number to comply with local regulations (usually taken from a pool of numbers we have access to from the relevant destination market)
    - Fixed SenderID - This is where the local markets require MailBIT to set a fixed SenderID, sometimes numeric, sometimes alpha, in order that messages are permitted to be delivered
  • What is Alphanumeric Sender ID ?
    The alphanumeric sender ID technology allows the sender to send messages using a custom, recognizable sender ID constructed from any combination of numeric and alpha characters (0-9, a-z, A-Z, _).
  • What is Numeric Sender ID ?
    Numeric Sender ID is the default sender type of an SMS message in standard MSISDN form. Recipients can reply to messages with a numeric sender ID, meaning that it can be used for two-way messages.
  • What is MSISDN ?
    An MSISDN is the phone number associated with a single SIM card, in other words, the number you call or send an SMS message to.
  • What is DLR (Delivery Reporting) ?
    Delivery reporting is a feature of SMS MT that reports back if the SMS message has been delivered, for every message sent. It is sourced directly from the handset.
  • What is Concatenated Messages ?
    A concatenated short message service (Long SMS message) is used to overcome the limit on the number of characters that can be sent in a single SMS text message transmission (usually English=160 chars and Unicode = 70 chars). With this method, the sending device divides the long message into smaller ones that get recombined at the receiving end, with each message charged as a single SMS message.
  • MT (Mobile Terminated) ?
    A mobile message routed from a client or an application and delivered to the end user’s mobile phone is a called a SMS MT (Mobile Terminated). The word Terminated means that the message is terminated (delivered) on a mobile device. It is also known as an Outbound SMS.
  • What is Outbound Message?
    An outbound message is a message routed from a client or an application and delivered to the end user’s mobile phone. It may also be regarded as a Mobile Terminated message or MT, signifying that the endpoint of the message is a mobile phone.
  • What is Unicode SMS?
    Industry standard allowing computers to consistently represent and manipulate text expressed in any of the world's writing systems. As an SMS MT feature, it allows any content to be sent within a message.
  • What is 2-Way SMS Messaging ?
    A system that incorporates both outbound (Mobile Terminated or MT) and inbound (Mobile Originated or MO) SMS into one fully-featured service.
    By using a dedicated mobile number or Long / short code, a 2-Way SMS user can send and receive SMS through a web messaging platform by using complete solutions or APIs.
  • What is Inbound Message ?
    An inbound message is a mobile message routed from an end user's mobile device and delivered to a mobile phone or an application. It may also be regarded as a Mobile Originated message or MO signifying that the starting point of a message is a mobile phone.
  • What is MO (Mobile Originated) ?
    A mobile message routed from an end user's mobile device and delivered to a mobile phone or an application.
    Incoming messages can be forwarded to SMPP, HTTP push or pull, or email. Also, they can trigger further actions - an automatic reply, opening of a support ticket etc.
  • What is SMS Keyword ?
    A word that clients choose in order to identify their campaign and inbound SMS messages. It is the first word that appears in the message before the blank space, and that end user is asked to include to the message they’re sending out to a company or institution. For example, a wine brand can offer customers to text Coffee (keyword) to a shortcode to participate in sweepstakes.
  • What is P2A (Person-2-Application) Messaging ?
    P2A (person-to-application) SMS messaging is the process of sending messages from a mobile user to an application. It is often referred to as Mobile Originated (MO). The process requires the end-user to start the interaction with a business or company by sending an SMS to an application. to participate in sweepstakes.
  • What is Premium SMS Number ?
    A Premium SMS number is a 3-7 digit number used for messaging that charges a premium price to the end user per sent SMS. End user pays a higher price of the message than for a normal P2P message.
  • What is Short Code ?
    A Short Code is a 3-6 digit number which enables sending and receiving of SMS messages, usually in SMS sweepstakes, polling, TV voting etc. With short codes, sending and receiving messages is limited to national borders. They can be leased from mobile network operators or through specialized messaging companies that also provide consultancy and tech support.
  • What is VLN (Virtual Long Number) ?
    A Virtual Long Number (VLN) is a typical mobile number provided by mobile operators, consisting of 11-12 digits (eg. 66894828888).
  • What is 2-Factor Authentication ?
    Two-Factor Authentication, also known as 2FA, is an extra layer of security that requires users to use both their online password and their mobile phone to verify their identity in order to access a service or a web app. In addition to using their service credentials to access sensitive data, the user also receives a one-time passcode or PIN number on his token or via SMS.
  • What SMS Blacklist ?
    A blacklist is a list of message recipients that decided to opt-out of receiving further SMS messages.
  • What Binary SMS Messages ?
    Binary SMS messages allow sending of various types of rich-content, such as transferring ringtones, telephone system settings and WAP-Push via text messaging.
  • What is Fixed Sender ID ?
    A predefined numeric sender identification (the mobile number that is displayed on the recipient's cell phone) that cannot be modified according to user needs and follows the standard MSISDN format -
    The ITU Telecommunication Standardization Sector recommendations limits the maximum length of an MSISDN to 15 digits. 1-3 digits are reserved for country code with prefixes not included.
  • What is Flash SMS ?
    A message that appears on the recipient's mobile screen directly. Recipient does not need go to the mobile phone inbox to read the message, nor is the message allocated to the SMS inbox.
  • What is Global Title ?
    A Global Title (GT) is an address used in the SCCP protocol for routing signaling messages on various telecommunications networks.
  • What is HLR (Home Location Register) ?
    HLR (Home Location Register) is a database that contains various information about all of the mobile subscribers of a mobile network such as the mobile numbers, services, whether the numbers have been ported to another network and similar information.
  • What is MNO (Mobile Network Operator) ?
    A mobile network operator or MNO, also known as a wireless service provider, wireless carrier, cellular company, or mobile network carrier, is a provider of wireless communications services that owns or controls all the elements necessary to deliver services to end-users, including radio spectrum allocation, wireless network infrastructure and other necessary components.
  • What is Mobile Number Portability ?
    Mobile Number Portability (MNP) enables mobile telephone users to retain their mobile telephone numbers when switching from one mobile network operator to another. Since its launch in Singapore in 1997, over a hundred markets today allow MNP. Most MNOs offer this service for free or for a nominal price, enabling users to change numbers or switch operators with ease.
  • What is OPT In SMS ?
    The opt-in function is connected with getting permission from the customer to send promotional messages to his or her's mobile number.
  • What is OPT Out SMS ?
    The opt-out function is an action where a customer requests the stopping of sending SMS messages to his or her's mobile number.
  • What is OTP (One-Time PIN) Code ?
    A one-time PIN code is a code that is valid for only one login session or transaction using a mobile phone. It is often used in two factor authentication or 2FA to provide an extra layer of security for the user when he uses an ATM machine or tries to login to a service from a different computer.
  • What is SMS Retry Mechanism ?
    Retry refers to the process of the SMSC retrying to deliver an SMS message that failed to be delivered during a time period the message is valid, which is usually 48 hours. If a delivery of a message fails the SMSC starts a retry procedure that tries to deliver the message periodically.
  • What is Silent Mobile Verification ?
    Silent Mobile Verification is a verification service that is an integral part of Mobile Identity. It is also known as HTTP Header Enrichment. Silent Mobile Verification works by matching the user’s phone number (MSISDN) with the Mobile Network Operator data smoothly without interupting user experience.
  • What is SMPP ?
    The short message peer-to-peer protocol (SMPP) is a telecommunications industry protocol for exchanging SMS messages between SMS peer entities such as short message service centers (SMSCs).
  • What is SMS Aggregator ?
    Mobile telecom company with multiple agreements with mobile operators to send and receive data in and out of the operator's SMSC, acting as an intermediary between companies (i.e. content and brand owners) that want to interact with end users (through their mobile phones; i.e. via SMS) and mobile operators.
  • What is SMS Delivery ?
    Distribution of mobile messages, including SMS and Premium SMS, directly to the end-users' mobile devices.
  • What is SMS Gateway ?
    An SMS gateway is, generally speaking, a point of entry or exit for SMS messages. It is a network node equipped for interfacing with another network that uses the same or different protocols. The most common protocols used are SMPP, HTTP, SS7
  • What is SMS Hubbing ?
    A new structure for international SMS traffic, reshaping international mobile inter-operability by implementing hubs to intermediate SMS traffic and offer a larger SMS coverage.
  • What is SMS Termination ?
    SMS termination refers to the delivery of an SMS message either from one mobile user to another (P2P) or from an application to a mobile user (A2P). It signifies that the message was delivered to a mobile phone user.
  • What is SMSC ?
    A short message service center (SMSC) is a mobile telecommunication networks element which stores, forwards, converts and delivers SMS messages and maintains unique timestamps in text messages.
  • What is SS7 ?
    Signaling System #7 (SS7) is a set of telephony signaling protocols which are used to set up most of the world's public switched telephone calls, also used in mobile messaging, prepaid billing and other applications.
  • What is TON/NPI Settings ?
    This SMS-MT feature allows senders to manage originator and destination settings.
  • What is UDH (User Data Header) ?
    User Data Header (UDH) is a binary structure which may be present at the start of a short message in an SMS. It does not contain any text, but rather specifies how the message should be processed. Basically, it's a part of the SMS which tells the receiving handset what type of message being sent. This is done to ensure correct SMS message delivery.