SMS(Sender IDs)

Sender IDs

A Sender ID is a unique name or standard mobile number that shows in the “from” field of your text messages on your phone.

So, instead of the message coming from a system generated long number, you can choose your company name, campaign name or even a standard mobile number. By using a Sender ID, your customers will immediately recognise who the SMS text message is from. Take a look how Greenhead College uses their Sender ID.

Recipients can’t reply to text messages sent using a Sender ID making it ideal for sending SMS messages that don’t need a response. But remember, you will need to include clear instructions in the message on how recipients can opt-out. By doing this, you’ll be sticking to the industry codes of best practice with every send.

Using a Sender ID for your SMS communications

To have truly effective and engaging SMS communications, your recipients must know who the message is coming from. With multiple Sender ID options available, you can make this easier for customers and make your brand even more memorable.

What is a Sender ID?

A Sender ID is a numeric or alphanumeric contact that identifies who has sent an SMS message. Sender IDs appear at the top of text message conversations and help users recognise what business has sent a particular message.

Types of Sender IDs

Sender IDs aren’t just limited to your standard mobile number set-up. With customisable options, your business can improve brand recognition and engagement with recipients.

There are three different types of Sender IDs; Custom Words, Dedicated Numbers, and Shared Numbers. Read on to get into the nitty-gritty of these Sender ID options.

Custom Words

A Custom Word can use up to 11 alphanumeric characters as the Sender ID. Your Custom Word could be your business name, a department within your business or any other word/phrase you deem suitable.

Custom Words are unique to your company and are a great way to increase brand awareness and recognition. SMSGlobal’s web SMS platform does not charge additional payments to send from a Custom Word.

Unlike other Sender IDs, Custom Words do not support two-way SMS communication. Custom Words are often used for transactional SMS when replies are not needed and most popular amongst airlines, banks, and insurance agencies.

Dedicated Numbers

A Dedicated Virtual Number consists of up to 16 digits and can only be used by your business. Virtual Numbers support Two Way SMS conversations but must be purchased from an SMS provider like SMSGlobal.

Dedicated Virtual Numbers come in two forms; short code and long code.

Long code: Long code numbers consist of 11-16 digits depending on which country you’re sending from. They’re cheaper than short code numbers however they’re slightly more challenging to remember given their length.

Short code: Short code Dedicated Numbers can be between 4-8 digits, dependent on the country you’re sending within. Short code numbers are easy to remember making them perfect for conversations that begin from the customer end. Many businesses implement short codes for text-to-win competitions, customer feedback, and customer requests.

Which type of Sender ID should I choose?

The best Sender ID for your business will depend on several factors. Below we’ve detailed the benefits of each so you can pick the best option for your SMS communications and business needs.

Custom Words

  • Free to use through our online SMS platform, MXT
  • Clearly identifies your business
  • Unique to your brand
  • Illustrates an increased level of professionalism
  • Improves brand awareness
  • Considered best practice for finance, insurance, and government institutions

Short Code Dedicated Number

  • Very easy to remember
  • Unique to your business
  • Supports Two-Way messaging
  • Supports Keywords & Triggers responses
  • Ideal for text-to-win competitions and customer requests

Long Code Dedicated Number

  • Unique to your business
  • Supports Two-Way SMS
  • Supports Keywords & Triggers
  • More cost-effective than Short Code Dedicated Numbers

Shared Numbers

  • Free to use through the MXT gateway
  • Supports Two-Way SMS (within 48 hours of sending)
  • Perfect for small businesses beginning their implementation of SMS communications

. Dynamic SMS Service

Nothing can beat Dynamic SMS, when it comes to sending text messages to a dedicated group of users. Usually sending dedicated text via normal method can turn out to be a tough task. But all thanks to tools like Dynamic SMS, this can be done within a blink of an eye.

In simple terms, Dynamic SMS lets you modify and send content as per the receiver and that too in bulk quantity! Dynamic SMS generally works on the Excel plug in, which lets you forward customized texts with a single click. The use of Excel sheets gives you an added advantage of storing bulk data in a single space which can be further uploaded on the send panel through a single click.

This tool not just takes away the stress of sending customized messages in bulk but also lets you monitor and analyse its impact. 


You’ll sometimes see a distinction between “peer-to-peer messaging” and “application-to-peer messaging,” wherein P2P implies communication between two mobile devices, and A2P implies communication between software and a mobile device. The SMPP applies to both because software and mobile devices can use this same protocol to exchange SMS messages with mobile devices.

How does the SMPP work?

When an SMS-enabled device or application wants to send a text to another device, it initiates an SMPP session with a cellular carrier’s Message Center (MC), also known as an SMSC.

During the session, the device and the Message Center use the SMPP protocol to send requests (or commands) and respond to one another. They package these requests and responses as “Protocol Data Units” (PDUs). It’s how they define whether an External Short Message Entity (ESME) is going to send or receive an SMS communication (or do both), and how they actually relay the information.

It’s kind of like this: the two entities that need to exchange messages have to speak through a mediator. The cellular carrier’s Message Center establishes which entity is sending or receiving and then accepts or rejects the SMS transmission on behalf of the recipient. If one of the entities needs to use a gateway to communicate via SMS, then the gateway acts as a mediator as well, relaying information to and from the Message Center.

If the transmission is rejected, an error code relays what went wrong. For example, it can specify an invalid request, destination, message ID, or message length.

SMPP sessions

There are four types of SMPP sessions, three of which are initiated by the ESME, and the MC initiates the other.

Transmitter (TX)

An ESME will initiate a session as a transmitter in order to send SMS messages to a mobile device. It can also use a transmitter session to cancel previously sent messages. Since it sends these messages to a mobile device, they’re also known as mobile terminated messages.

Receiver (RX)

An ESME will initiate a session as a receiver in order to receive SMS messages from a mobile device. Since these messages originate from the mobile device, they’re also known as mobile originated devices.

Transceiver (TRX)

Transceiver sessions allow ESMEs to both send and receive SMS messages. The oldest version of the SMPP doesn’t allow this type of session.

Outbind session

An outbind session is simply an SMPP session that the Message Center initiates. 

Protocol data units (PDUs)

PDUs contain the actual commands and responses the SMSC and MC send to each other, formatted according to the protocol. 

At the start of every session, a bind command defines the type of interaction that will take place. For example, to initiate a transmitter session, the SMSC sends a PDU with the command bind_transmitter. This initial PDU also contains the ESME’s identification, type, and a password. It also specifies which version of the SMPP the ESME is using, so the MC knows how to interpret the commands and which PDUs can be used.

PDUs also define which direction an SMS communication is coming from. If an ESME wants to send a text message, for example, the SMSC sends the request submit_sm to the MC.

SMPP versions

There are three versions of the SMPP:

  • SMPP v3.3
  • SMPP v3.4
  • SMPP v5.0

SMPP v3.3 is the oldest version of the SMPP. Later versions added new session types (transceiver sessions), support for additional technologies, and new PDU parameters (some of which are optional). 

Since the SMPP version determines how the two entities can interact, every session has to define what version the ESME is using.

What is the SMPP used for?

The SMPP is a key component of modern SMS communications, and it’s used in a broad range of applications. Here are just a couple of use cases.

Business texting uses the SMPP to send text messages from a software program to individual phone numbers or a mass list of them. This includes everything from marketing messages to information services, appointment reminders, chatbot services, and even password reset requests.

Cellular Internet of Things (IoT) devices such as smart meters use the SMPP to transmit updates about resource consumption and location status. When an event like a break-in or fire triggers a smart alarm system, it uses the SMPP to message the building owner, potentially with a link that allows them to access a camera feed.

Does your IoT device need to use SMS?

If your IoT device relies on cellular connectivity, it’s probably going to use SMS to transmit and receive information. But that doesn’t mean you have to use SMPP. SMPP is a complicated protocol that most IoT manufacturers can avoid relying on for SMS.

emnify is an IoT connectivity platform. Not only do we enable IoT manufacturers to take advantage of cloud native connectivity, but we also simplify SMS communications for your IoT device. Using our RESTful API, your devices can communicate over SMS using JavaScript Object Notation (JSON), and you don’t have to worry about SMPP.


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