A network built to send and receive text messages to and from mobile telephones around the world.

What is an Enterprise-level SMS gateway?

Enterprise SMS gateway software allows businesses to transmit and receive bulk SMS messages to mobile phone networks around the world. Gateway providers like CallFire and Clickatell have special agreements with the major mobile carriers around the world to send two-way SMS traffic. These gateway providers can send text message traffic to mobile phone network SMS centers, or SMSCs, which are responsible for relaying those messages to the intended mobile phone. Enterprise-level businesses can utilize these SMS gateway solutions to send and receive bulk SMS text messages from all around the world.

How do SMS gateways work?

Gateway providers like CallFire have special agreements with the major mobile carriers around the world to send two-way SMS traffic. These gateway providers, also known as SMS aggregators, will send and receive SMS traffic to and from the mobile phone networks' SMSCs, which are responsible for relaying those messages to the intended mobile phone. The aggregators then receive feedback from the SMSC as to the status of the delivery of that message. This relationship between the aggregator and SMSC allows for the transmission of a large number of SMS messages in mobile marketing campaigns.

What is an SMS aggregator?

SMS gateway software providers are often referred to as aggregators. The aggregators have multiple agreements with the large mobile network providers, such as Verizon and T-Mobile, to send and receive text messages through these networks' SMS centers.

What is a direct-to-mobile gateway?

Direct-to-mobile gateways allow SMS text messages to be sent and/or received by email, from webpages or from other software applications, by acquiring a subscriber identity module (SIM) card. Direct-to-mobile gateways are different from SMS aggregators because they are installed on an organization's own network and connect to a local mobile network. The connection to the mobile network is made by acquiring a SIM card from the mobile operator and installing it in the gateway. Direct-to-mobile gateway appliances are usually used when the texts per month number in the low hundreds or low thousands, and are not used as an enterprise solution.

What are SMS centers (SMSCs)?

A short message service center (SMSC) is responsible for handling the relay of SMS text messages for the major telecom carriers like Verizon and T-Mobile. When an SMS message is sent from a mobile phone, it will reach an SMSC. The SMSC then forwards the SMS message towards the destination. The main duty of an SMSC is to route SMS messages and regulate the process. If the recipient is unavailable (for example, when the mobile phone is switched off), the SMSC will store the SMS message. It will forward the SMS message when the recipient is available.
Most of the major carriers run their own SMSCs. You must know the address of the wireless network operator's SMSC in order to use SMS messaging with your mobile phone. Typically, an SMSC address is an ordinary phone number in the international format. A mobile phone should have a menu option that can be used to configure the SMSC address. The SMSC address is usually preset in the SIM card by the wireless network operator, which means you do not need to make any changes to it.

What are SS7 providers?

SMS gateway providers are often referred to as SS7 providers. SS7 refers to a protocol of transmitting and receiving a text message from a mobile phone to the large carriers' SMSCs. The SMS gateway providers, or SS7 providers, have special agreements with the large mobile networks to send and receive messages via the mobile networks' SS7 protocol.

What is SS7 protocol?

SS7 refers to the protocol of transmitting and receiving text from the large mobile carriers to the mobile phone destinations. Aggregator or SMS gateway providers don't have access to SS7 protocol, so they must drive all their traffic to the large mobile networks.

What is a message delivery report?

After receiving an SMS message, the recipient mobile phone will send back a message delivery report to the SMSC to inform whether there are any errors or failures. (Example causes: unsupported SMS message format, not enough storage space, etc). This process is transparent to the mobile user. If there is no error or failure, the recipient mobile phone sends back a positive delivery report to the SMSC. Otherwise, it sends back a negative delivery report to the SMSC.

If the sender requested a status report earlier, the SMSC sends a status report to the sender when it receives the message delivery report from the recipient.
If the SMSC does not receive the message delivery report after a period of time, it concludes that the message delivery report has been lost. The SMSC then resends the SMS message to the recipient.

Related Terms

Voice Broadcast

Providers

References

Wikipedia: SMS gateway definition
Techopedia
Developer's Home definition 
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