CELLULAR ARCHITECTURE FOR SMS- TXT BASED MOBILE MARKETING Course Faculty: Mrs Yasmin Malik Venue: IBA City Campus, Karachi Course Start Date: Spring 2012 (Feb 1) MIS553: Mobile Marketing Strategies

Some Notes on Basic Cellular Network Architecture  Every mobile network essentially has two components:  The “wireless” part  The “wired” part  The “wireless” part encompasses the mobile subscriber/phone, the associated Base Station (BS) and Base Station Control/Switching Unit and a Gateway (often called the Gateway Mobile Switching Centre or G-MSC)  The “wired” part starts at the Gateway and involves what is known as the “Backbone” or “Wired Backhaul” which usually makes up the long distance part of the network  Any SMS-Txt campaign (and its associated software) must, at some point, make use of the “wired” part of the network

2G/2.5/2.75G Cellular Network Architecture Access Service Network (ASN) = Cellular Base Station + Gateway Connectivity Service Network (CSN) that allows inter-connection to other networks and manages the ASN/subscribers: Billing, Authentication, CRM, DNS, IMS ASN or MSC Gateway connected to IP Core PSTN The ASN Gateway is more commonly known as the G-MSC or Gateway Mobile Switching Center (It interacts with the associated HLR - Home Location Register- and VLR – Visitor Location Register – databases to determine subscriber data) 2G/3G Mobile networks Other Operators CSN BS Outdoor RF Section (BTS = Base Station Transceiver Station) BS Control and Switching Unit (BSC) Mobile Subscriber/User The Base Station Subsystem (BTS + BSC) handles radio communications between 2G, 2.5 G and 2.75G mobile devices or mobile users

SMSC: 1. Responsible for handling SMS operations 2. Upon sending from the mobile user, the SMS message first reaches the SMSC 3. It is then forwarded by the SMSC to the destination number/mobile user 4. Main function is to route and regulate the SMS delivery process 5. Normally there is one SMSC per MSC MSC: Connects the mobile user on the wireless part of the network to the nearest SMSC and acts as a gateway between the “Wireless” and “Wired” part of the Operator’s telecom network Short Message Service Centre (SMSC) Architecture Diagram

Some Notes on the SMSC  The first point of interaction for a text message or SMS message is the SMSC (Short Message Service Centre)  When a mobile user sends an SMS message to another mobile user, the message gets stored in the SMSC that is directly relevant to the sender i.e. that which is directly associated with the sender according to the user’s location and Operator  The SMSC delivers the SMS to the destination user when they are available on the network i.e. when their mobile phone is switched on and registered onto the network  SMSC basically operate on a “store and forward” principle  The main function of the SMSC is to route and regulate messages  For example: If the recipient is unavailable in case their mobile phone is switched off, the SMSC will store the SMS message  The SMS gets forwarded when the recipient becomes available on the network  An SMS message is stored temporarily in the SMSC if the recipient mobile phone is offline. It is possible to specify a cutoff period after which the SMS message will be deleted from the SMSC  Note that once deleted, the SMS message will no longer be available for dispatch to the recipient mobile phone (even if it becomes online)  SMSC also handle things like Message Status Reports: users can set a flag in the SMS message to notify the SMSC that a status report about the delivery of this SMS message is required  This status report is sent to the SMS sender in the form of an SMS message

Some Notes on Short Codes  Short Codes Definition = Special telephone numbers, usually 4 to 6 digits long, used in mobile marketing campaigns where mobile subscribers can participate in any given campaign by sending a test message to the advertised short code.  Short codes are widely used for value-added services such as television program voting, ordering ring tones, charity donations and mobile services.  Messages sent to a short code can be billed at a higher rate than a standard SMS and may even subscribe a customer to a recurring monthly service that will be added to their mobile phone bill until they text, for example, the word "STOP" to terminate the service.  In Pakistan, short codes comprise 4 digits and have to be purchased from the telecoms Regulator i.e. the PTA which allocates specific short codes and their usage duration.  Media buying agencies (MindShare), technology/content provider companies (Converge) or the telecom Operator can undertake the short code purchasing process with the PTA on behalf of the brand (Lux).  Operators usually charge a premium for texting in to the short code to recover costs and to generate additional revenue.  Short codes in Pakistan can be typically charged at Rs 5-25 depending on the type of campaign, the strength of the brand or the overall cost of the campaign. In the industry, this rate is often referred to as the “price point”  Revenue sharing of short code is typically where the Operator usually retains the higher percentage i.e. 70% of the cost of the short code. But it can also be (Telenor) or even (Mobilink) depending on the bargaining power of the Operator…  Hence short codes are a very lucrative source of revenue for Operators!

Tracking of Txts Sent To/From Short Code  In a simple Short-Code based campaign, a fairly simple tracking mechanism (software) can be utilized to:  Account for how many SMS are sent to a short code  Generate correct response SMS (e.g. “Thank you for participating. You have entered into a prize draw) is sent out to mobile subscriber  Automated prize draw and resultant SMS notification to winners  The software can be part of the Operator’s infrastructure or can be an independent software operated by a third party (Converge) which has been given access to the Operator’s SMSC network  However, more sophisticated SMS campaigns require more than simple tracking and automated delivery of SMS…