Touch Screens

A touchscreen is an electronic visual display that can detect the presence and location of a touch within the display area. The term generally refers to touching the display of the device with a finger or hand.

Types of Touch Screen:

Dispersive signal technology:

Introduced in 2002 by 3M, this system uses sensors to detect the Piezoelectricity in the glass that occurs due to a touch. Complex algorithms then interpret this information and provide the actual location of the touch. The technology claims to be unaffected by dust and other outside elements, including scratches. A downside is that after the initial touch the system cannot detect a motionless finger.

Optical imaging:

This is a relatively modern development in touchscreen technology, in which two or more image sensors are placed around the edges (mostly the corners) of the screen. Infrared back lights are placed in the camera's field of view on the other side of the screen. A touch shows up as a shadow and each pair of cameras can then be pinpointed to locate the touch or even measure the size of the touching object (see visual hull). This technology is growing in popularity, due to its scalability, versatility, and affordability, especially for larger units.

Infrared:

An infrared touchscreen uses an array of X-Y infrared LED and photodetector pairs around the edges of the screen to detect a disruption in the pattern of LED beams. These LED beams cross each other in vertical and horizontal patterns. This helps the sensors pick up the exact location of the touch. A major benefit of such a system is that it can detect essentially any input including a finger, gloved finger, stylus or pen. It is generally used in outdoor applications and point of sale systems which can't rely on a conductor (such as a bare finger) to activate the touchscreen. Unlike capacitive touchscreens, infrared touchscreens do not require any patterning on the glass which increases durability and optical clarity of the overall system.

Resistive:

A resistive touchscreen panel comprises several layers, the most important of which are two thin, transparent electrically-resistive layers separated by a thin space. These layers face each other, with a thin gap between. One resistive layer is a coating on the underside of the top surface of the screen. Just beneath it is a similar resistive layer on top of its substrate. One layer has conductive connections along its sides, the other along top and bottom. When an object, such as a fingertip or stylus tip, presses down on the outer surface, the two layers touch to become connected at that point: The panel then behaves as a pair of voltage dividers, one axis at a time.

                                        

Capacitive:

A capacitive touchscreen panel consists of an insulator such as glass, coated with a transparent conductor such as indium tin oxide (ITO). As the human body is also an electrical conductor, touching the surface of the screen results in a distortion of the screen's electrostatic field, measurable as a change in capacitance. Different technologies may be used to determine the location of the touch. The location is then sent to the controller for processing. Unlike a resistive touchscreen, one cannot use a capacitive touchscreen through most types of electrically insulating material, such as gloves; one requires a special capacitive stylus, or a special-application glove with an embroidered patch of conductive thread passing through it and contacting the user's fingertip. This disadvantage especially affects usability in consumer electronics, such as touch tablet PCs and capacitive smartphones in cold weather.

                                                             

Self-capacitance:

Self-capacitance sensors can have the same X-Y grid as mutual capacitance sensors, but the columns and rows operate independently. With self-capacitance, the capacitive load of a finger is measured on each column or row electrode by a current meter. This method produces a stronger signal than mutual capacitance, but it is unable to resolve accurately more than one finger, which results in "ghosting", or misplaced location sensing.

References:

·         http://en.wikipedia.org/wiki/Touchscreen

·         http://scienceline.org/2012/01/okay-but-how-do-touch-screens-actually-work/ 

Asynchronous Transfer Mode (ATM)

Asynchronous Transfer Mode (ATM) is a high-performance, cell-oriented switching and multiplexing technology that utilizes fixed-length packets to carry different types of traffic. ATM is a technology that will enable carriers to capitalize on a number of revenue opportunities through multiple ATM classes of services; high-speed local-area network (LAN) interconnection; voice, video, and future multimedia applications in business markets in the short term; and in community and residential markets in the longer term.

In ATM networks, all information is formatted into fixed-length cells consisting of 48 bytes (8 bits per byte) of payload and 5 bytes of cell header. The fixed cell size ensures that time-critical information such as voice or video is not adversely affected by long data frames or packets. The header is organized for efficient switching in high-speed hardware implementations and carries payload-type information, virtual-circuit identifiers, and header error check.

ATM is connection oriented. Organizing different streams of traffic in separate calls allows the user to specify the resources required and allows the network to allocate resources based on these needs. Multiplexing multiple streams of traffic on each physical facility (between the end user and the network or between network switches)—combined with the ability to send the streams to many different destinations—enables cost savings through a reduction in the number of interfaces and facilities required to construct a network.

ATM standards defined two types of ATM connections: virtual path connections (VPCs), which contain virtual channel connections (VCCs). A virtual channel connection (or virtual circuit) is the basic unit, which carries a single stream of cells, in order, from user to user. A collection of virtual circuits can be bundled together into a virtual path connection. A virtual path connection can be created from end-to-end across an ATM network. In this case, the ATM network does not route cells belonging to a particular virtual circuit. All cells belonging to a particular virtual path are routed the same way through the ATM network, thus resulting in faster recovery in case of major failures.

The benefits of ATM are the following:

• high performance via hardware switching
• dynamic bandwidth for bursty traffic
• class-of-service support for multimedia
• scalability in speed and network size
• common LAN/WAN architecture
• opportunities for simplification via VC architecture
• international standards compliance

Reference:

http://www.telecomspace.com/vop-atm.html

Geographic Information System(GIS)

A Geographic Information System, Geographical Information Science, or Geospatial Information Studies is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology.

GIS software systems link features on a map to descriptive information known as attribute data. This allows GIS to simultaneously leverage both the visual advantages of a map and the data storage and retrieval advantages of a relational database. The old adage that “a picture is worth a thousand words” is very relevant in this context, as many organizations have substantial amounts of data in tabular form that, when displayed on a map, become much easier to understand and analyze.

The data of GIS is represented in either Raster or Vector data.

Raster: 

The information is displayed in Pixels                                                                  
Raster data type consists of rows and columns of cells, with each cell storing a single value. Raster data can be images (raster images) with each pixel (or cell) containing a color value.

Raster data is stored in various formats, from a standard file-based structure of TIF, JPEG, etc. to binary large object (BLOB) data stored directly in a relational database management system (RDBMS)

Vector:

Vector data is linear and contains points, lines and polygons; Each of these geometries are linked to a row in a database that describes their attributes. For example, a database that describes lakes may contain a lake's depth, water quality, pollution level.
                                                         

A GIS can be thought of as a system—it digitally creates and "manipulates" spatial areas that may be jurisdictional, purpose or application-oriented for which a specific GIS is developed. Hence, a GIS developed for an application, jurisdiction, enterprise or purpose may not be necessarily interoperable or compatible with a GIS that has been developed for some other application, jurisdiction, enterprise, or purpose.

GIS technology enables telecommunication professionals to integrate location-based data into their analytical and management processes.  The use of location based analysis can aid network planning and operations, marketing and sales, customer care, and data management.

A GIS based Telecom applications are ideally suited to meet all of the challenges of rapidly developing Telecom industry. It is not only capable of supporting standard GIS functions, but because of its specially developed telecom data model and functionalities, also supports various telecom inventory and OSS related requirements. It enables the Telco engineers to model various OSP objects like manholes, trenches, ducts and cables of all types; termination boxes, panels and splices / connections as well as all kinds of equipment up to port level.

References:

http://en.wikipedia.org/wiki/Geographic_information_system

International Mobile Equipment Identity

The International Mobile Equipment Identity or IMEI is a number, usually unique, to identify GSM, WCDMA, and iDEN mobile phones, as well as some satellite phones. It is usually found printed inside the battery compartment of the phone. It can also be displayed on the screen of the phone by entering *#06# into the keypad on most phones.

The IMEI number is used by the GSM network to identify valid devices and therefore can be used for stopping a stolen phone from accessing the network in that country. For example, if a mobile phone is stolen, the owner can call his or her network provider and instruct them to "blacklist" the phone using its IMEI number. This renders the phone useless on that network and sometimes other networks too, whether or not the phone's SIM is changed.

The IMEI is only used for identifying the device and has no permanent or semi-permanent relation to the subscriber. Instead, the subscriber is identified by transmission of an IMSI number, which is stored on a SIM card that can (in theory) be transferred to any handset. However, many network and security features are enabled by knowing the current device being used by a subscriber.

The Structure of an IMEI Number/IMEISV (IMEI Software Version)

The IMEI (14 decimal digits plus a check digit) or IMEISV (16 digits) includes information on the origin, model, and serial number of the device. The model and origin comprise the initial 8-digit portion of the IMEI/SV, known as the Type Allocation Code (TAC). The remainder of the IMEI is manufacturer-defined, with a Luhn check (it is an algorithm used to validate ID) digit at the end. 

• AA: - These two digits are for the Reporting Body Identifier, indicating the GSMA approved group that allocated the TAC (Type Allocation Code).
• BBBBBB: - The remainder of the TAC
• CCCCCC: - Serial sequence of the Model

D or EE: - Luhn check digit of the entire model or 0 (This is an algorithm that validates the ID number) / Software Version Number (SVN).

              

For example, the old style IMEI code 35-209900-176148-1 or IMEISV code 35-209900-176148-23 tells us the following:

TAC: 35-2099 - issued by the BABT (code 35) with the allocation number 2099

FAC: 00 - indicating the phone was made during the transition period when FACs were being removed.

SNR: 176148 - uniquely identifying a unit of this model

CD: 1 so it is a GSM Phase 2 or higher

SVN: 23 - The "software version number" identifying the revision of the software installed on the phone. 99 is reserved.

Reference

http://en.wikipedia.org/wiki/International_Mobile_Equipment_Identity

Intrusion Detection System

An intrusion detection system (IDS) is a device or software application that monitors network and/or system activities for malicious activities or policy violations & produces reports to a Management Station.

Intrusion detection and prevention systems (IDPS) are primarily focused on identifying possible incidents, logging information about them, and reporting attempts. In addition, organizations use IDPSes for other purposes, such as identifying problems with security policies, documenting existing threats, and deterring individuals from violating security policies. IDPSes have become a necessary addition to the security infrastructure of nearly every organization

Types of IDS

    *      Network intrusion detection system (NIDS)

It is an independent platform that identifies intrusions by examining network traffic & monitors multiple hosts. In a NIDS, sensors are located at choke points in the network to be monitored, often in the demilitarized zone (DMZ) or at network borders. Sensors capture all network traffic & analyze the content of individual packets for malicious traffic. An example of a NIDS is Snort.

    *      Host-based intrusion detection system (HIDS)

It consists of an agent on a host that identifies intrusions by analyzing system calls, application logs, file-system modifications (binaries, password files, capability databases, Access control lists, etc.) & other host activities & state. An example of a HIDS is OSSEC (a free, open source host-based intrusion detection system (IDS). It performs log analysis, integrity checking, Windows registry monitoring, rootkit detection, time-based alerting and active response).

    *      Stack-based intrusion detection system (SIDS)

This type of system consists of an evolution to the HIDS systems. The packets are examined as they go through the TCP/IP stack & therefore, it is not necessary for them to work with the network interface in promiscuous mode. This fact makes its implementation to be dependent on the Operating System that is being used.

Reference:

http://en.wikipedia.org/wiki/Intrusion_detection_system

Mobile Operating system

A mobile operating system (mobile OS) is the operating system that controls a smartphone, tablet, PDA, or other mobile device. Modern mobile operating systems combine the features of a personal computer operating system with touchscreen, cellular, Bluetooth, WiFi, GPS mobile navigation, camera, video camera, speech recognition, voice recorder, music player, Near field communication, personal digital assistant (PDA), and other features.

Common software platforms:

Android from Google Inc.(open source, Apache)

• Android was developed by a small startup company(Android Inc.) that was purchased by Google Inc. Android is an open source, Linux-derived OS backed by Google; Used by Intel, HTC, ARM, Samsung, and Motorola.
• Programmed in  C, C++, Java.

BlackBerry OS from Research in Motion (closed source, proprietary)

• This OS is focused on easy operation and was originally designed for business. Recently it has seen a surge in third-party applications and has been improved to offer full multimedia support. Currently Blackberry's App World has over 50,000 downloadable applications; used in BlackBerry Phones
• Programmed in  Java.

iOS from Apple Inc. (closed source, proprietary)

• The Apple iPhone, iPod Touch, iPad, and second-generation Apple TV all use an operating system callediOS, which is derived from Mac OS X.
• Programmed in  C, C++, Objective-C.

Symbian OS from the Nokia and Accenture(open public license)

• Symbian has the largest share in most markets worldwide, but lags behind other companies in the relatively small but highly visible North American market. It has been used by many major handset manufacturers, including BenQ, Fujitsu, LG, Mitsubishi, Motorola, Nokia, Samsung, Sharp, and Sony Ericsson.
• Programmed in C++.

Windows Phone from Microsoft (closed source, proprietary)

• Microsoft unveiled its next-generation mobile OS, Windows Phone. The new mobile OS includes a completely new over-hauled UI inspired by Microsoft's "Metro Design Language". It includes full integration of Microsoft services such as Windows Live, Zune, Xbox Live and Bing, but also integrates with many other non-Microsoft services such as Facebook and Google accounts
• Programmed in  .NET (Silverlight/XNA).

webOS from HP (certain parts open sourced)

• webOS is a proprietary mobile operating system running on the Linux kernel, initially developed by Palm, which launched with the Palm Pre
• Programmed in  C.

Reference:

• http://en.wikipedia.org/wiki/Mobile_operating_system

Cloud Computing

Cloud computing is the delivery of computing as a service rather than a product, whereby shared resources, software, and information are provided to computers and other devices as a metered service over a network.

Cloud Computing Architecture

• Client: A cloud client consists of computer hardware and/or computer software that relies on cloud computing for application delivery.
• Application: Cloud application services deliver software as a service over the Internet, eliminating the need to install and run the application on the customer's own computers and simplifying maintenance.
• Platform: Cloud platform services deliver a computing platform and/or solution stack as a service, often consuming cloud infrastructure and sustaining cloud applications.
• Infrastructure: Cloud infrastructure services deliver computer infrastructure – typically a platform virtualization environment – as a service, along with raw (block) storage and networking.
• Server: The server layer consists of computer hardware and/or software products that are specifically designed for the delivery of cloud services, including multi-core processors, cloud-specific operating systems and combined offerings.

Types of Cloud Computing

                                          

• Public cloud: A public cloud is one based on the standard cloud computing model, in which a service provider makes resources, such as applications and storage, available to the general public over the Internet.
• Community cloud: Community cloud shares infrastructure between several organizations from a specific community with common concerns whether managed internally or by a third-party, hosted internally or externally.
• Hybrid cloud: Hybrid cloud is a composition of two or more clouds that remain unique entities but are bound together, offering the benefits of multiple deployment models.
• Private cloud: Private cloud is infrastructure operated solely for a single organization, whether managed internally or by a third-party and hosted internally or externally.

 Reference:

http://en.wikipedia.org/wiki/Cloud_computing

Telecom Billing - System Interfaces

This is an introduction to billing system and its system interfaces. Following diagram shows a typical architecture of a Telecom Billing System.

                                         

CRM/OMOF System: This is the first system from where a customer order is captured and customer is created into the system. CRM stand for Customer Relationship Management and OMOF stands for Order Management and Order Fulfillment.

Provisioning System: This system takes commands either from the Billing System or CRM/OMOF System to activate, de-activate and suspend the services. Both the architectures are valid and depends how architect design the whole setup.

Network Inventory System (NIS): This system maintains all the network identifiers like phone numbers, MSISDN, IP addresses, email addresses etc and technically it is called Network Inventory System. Depending on the system architecture, either CRM/OMOF of Billing System contacts NIS to obtain a required network identifier and assign it to the customer at the time of order creation.

Billing System: Telecom Billing system is a process of collecting usage, aggregating it, applying required usage and rental charges and finally generating invoices for the customers.

Network Switches: Network switches are responsible to provide all the services to the end customers based on what services have been provisioned for the customer. These systems are responsible of controlling calls, data download, SMS transfer etc and finally generating Call Detail Records.

Mediation System: The Mediation System collects CDRs from different network elements in different formats. Various network elements generate CDRs in ASN.1 format and some network elements have their own proprietary format of CDRs.

Data Ware House (DWH) System: This is a downstream system for the Billing System and usually keeps tons of historical data related to the customers. Billing System dumps various customers’ information into the DWH system. This information includes service usage, invoices, payments, discounts and adjustments etc. All this information is used to generate various types of management reports and for business intelligence and forecast.

Enterprise resource planning (ERP): An Enterprise Resource Planning (ERP) system provides modules to handle Financials, Human Resources, and Supply chain management etc. Billing System interface with this system is used to post all the financial transactions like invoices, payments, adjustments.

Payment Gateway: As such this is not necessarily be a complete system but it could be a kind of custom components which sits in between the Billing System and different payment channels like banks, credit card gateway, shops and retailers etc. All the payment channels use payment gateway to post payments to the billing system to settle down customer invoices.