What are the best app development companies in India?

Application Development includes research, new development, modifications, reuse, re- engineering, maintenance or any other activity that results in the finished application. As market changes, the way we do our business and spending on IT activities of our business also changes. This dynamic change not only creates pressure but also open the doors to new opportunities. Therefore today, IT giants must stay on the cutting edge of providing complex solutions with less time-to-market in an affordable manner to its customers.

iFour Technolab Pvt Ltd helps organizations to effectively manage their applications through customized solutions. We provide value to our clients by leveraging our techniques and practices to satisfy our customers’ requirements.
Some of our value adding features in our services is:

• Domain Knowledge: Our deep industry knowledge and technical expertise to deliver effective results. We provide services to reduce costs and increase productivity.
• Customized Application: Customized solutions to support individual business needs. We develop applications that are scalable, secure and easily maintainable.
• Application Maintenance Support: We ensure that our applications are working effectively and efficiently supporting all business requirements. We offer continuous maintenance and support services to ensure long term value adding to our customers.

iFour Technolab Pvt. Ltd. provides application development services in India for various platforms like web, desktop and mobile that includes iOS, Android and Windows mobile. We understand the importance of technology and platform selection and conduct a special walkthrough with customer to discuss and select the right technology platform that suits your requirement and IT infrastructure. We use cutting edge technology for application development and ensure that it is in sync with your IT infrastructure.  Throughout the project lifecycle our focus is on the organization and providing measurable results.

Types of Network Security

Network scanning is a scanning used to define vulnerabilities in a network. A scan can be used by security experts to shield the security of a network from an external attack. Hackers may use a scan to find vulnerabilities. Different types of scanning are as under,

Three–Way Handshake

TCP is connection-oriented, which indicates connection establishment is principal prior to data transmission between applications. This connection is possible using the process of the three-way handshake. The three-way handshake is applied for establishing the connection between protocols.

The three-way handshake procedure goes as follows:

• To launch a TCP link, the source sends a SYN packet to the destination (10.0.0.3:21).
• The destination, on getting the SYN packet, i.e., sent by the source, responds by referring a SYN/ACK packet back to the source.
• This ACK packet checks the arrival of the first SYN packet to the source.
• The source sends an ACK packet for the ACK/SYN packet sent by the receiver.
• This triggers an "OPEN" connection agreeing communication between the source and the destination, until any of them send a "FIN" packet or a "RST" packet to close the connection.

The TCP protocol keeps stateful connections for all connection-oriented protocols across
the Internet, and works the same as a normal telephone communication, in which one picks up a telephone receiver, hears a dial tone, and dials a number that generates ringing at the receiver end until a person picks up the receiver and tells, "Hello."

Stealth Scan(Half-Open Scan)

Stealth scan sends a single frame to a TCP port without any TCP handshaking or extra packet transfers. This is a scan type that leads a single frame with the expectation of a single response. The half-open scan partly opens a connection, but stops midway. This is also known as a SYN scan because it only directs the SYN packet. This stops the service from ever being reported of the incoming connection. The three-way handshake approach is also implemented by the stealth scan. The variation is that in the last stage, remote ports are recognized by examining the packets entering the interface and dismissing the connection before a new initialization was activated.

The process preludes the following:

• To start initialization, the client forward a single "SYN" packet to the destination server on the matching port.
• The server initiates the stealth scanning process, depending on the response sent.
• If the server forwards a "SYN/ACK" response packet, then the port is in "OPEN" state.
• If the response is advanced with an "RST" packet, then the port is in a "CLOSED" state.

NULL Scan

NULL scans direct TCP packets with all flags turned off. It is expected that closed ports will return a TCP RST. Packets received by open ports are rejected as invalid. It sets all flags of TCP headers, such as SYN, ACK, FIN, RST, URG and PSH, to NULL or unassigned. When any packets reach at the server, BSD networking code notifies the kernel to drop the incoming packet if a port is open, or sends an RST flag if a port is closed. This scan uses flags in the opposite fashion as the Xmas scan, but gives the similar output as FIN and Xmas tree scans. Many network codes of major operating systems can behave inversely in terms of responding to the packet, ex, Microsoft versus UNIX. This method does not helpful for Microsoft operating systems. Command line for null scanning with NMAP is " -sN"
Advantage:
It evades IDS and TCP three-way handshake.
Disadvantage:
It is helpful only for UNIX.

Network scanning scans networks for vulnerabilities in the security of that network. If there is a vulnerability with the safety of the network, it will give a report back to a hacker who may use this information to exploit that network bug to gain entry to the network or for other malicious actions.

Access Control Domain

Access control Domain encompasses :

• Discretionary, Mandatory, and Non-Discretionary models 
• Identification methods, Authentication methods
• Accountability, monitoring, and auditing practices 
• Intrusion detection systems/Intrusion Prevention Systems 
• Likely threats to access control practices and technologies 
• A Framework that dictates how Subjects access Objects

The types of Access Control are :

• DAC
• MAC
• RBAC 

Discretionary Access Control – DAC

A system that uses discretionary access control (DAC) allows the holder of the resource to specify which subjects can access specific resources. This model is called discretionary as the control of access is based on the discretion of the owner.

For example, a manager for a definite department in the Custom software development company might be made the holder of the files and resources within his/her domain.

The most common application of DAC is through ACLs, which are spoken and fixed by the owners and enforced by the operating system.

• DAC permits the privileges i.e. granting and revoking of access control to be left to the discretion of the individual users
• It is highly flexible 
• Not appropriate for –
  -- High assurance systems, e.g. a military system 
  -- Many complex commercial security requirements 
• It is Identity-based 

Mandatory Access Control –MAC

In a mandatory access control (MAC) model, users and data owners do not have asmuch liberty to determine who can access files. The operating system makes the final conclusion and can outweigh the users’ wishes.

This model is much more structured and strict and is based on a security label system. Users are provided a security clearance (secret, top secret, confidential, and undefined), and data is classified in the same way. The clearance and grouped data is stored in the security labels, which are bound to the specific subjects and objects.

A given IT infrastructure in software development company can implement MAC systems in many places and at different levels. OS uses MAC to guard files and directories.

Database management systems apply MAC to regulate access to tables and views. Best commercially available application systems apply MAC, often independent of the operating systems and/or DBMSs on which they are installed.

OS constrains the ability of a subject or initiator to access or perform some operation on the object. Subject is usually a process thread and objects are constructs like files, tcp/udp ports, shared memory segments etc.

Whenever Subject tries to access Object, an authorization rule enforced by the operating system kernel inspects the security attributes and chooses whether access can take place.

Information classification is necessary, label-based

• Well suited to the requirements of government and industry organizations that process classified and sensitive information 
• Such environments usually require the ability to control actions of individuals beyond just an individual's capability to access information permitting to how that information is labeled based on its sensitivity 

RBAC 

• In RBAC model, a role is well-defined in terms of the tasks and operations that the role will need to carry out, whereas a DAC sketches which subjects can access what objects. 
• RBAC uses a centrally administrated set of controls to determine how subjects and objects act together. This type of model allows access to resources to be based on the role the user holds within the company example Software Development Company. 
• A role can be thought of as a set of transactions that a user or set of users can perform within the context of an organization i.e. a collection of permissions.
• A transaction can be thought of as a transformation procedure plus a set of associated data items 
• Roles are group oriented; created for job functions 
• Roles are plotted on the principle of least privilege 
• Role-based access control policy bases access control decisions on the functions a user is permitted to perform within an organization 
• RBAC provides a means of naming and describing many-to-many relationships between individuals and rights 
• A user has access to an object based on the assigned role. 
• Roles are defined based on job functions. 
• Permissions are defined based on job authority and responsibilities within a job function. 
• Operations on an object are invocated based on the permissions. 
• The object is concerned with the user’s role and not the user. 

Conclusion: 

Thus, the Custom Software Development Company should carry out structured ways for Access Control and assigning roles to the employees based on the privileges. This leads to secure access and intact security in the company or a firm which restrict the entities from using unauthorised information.

Mobile OS Architecture Trends

The design of Mobile OS has experienced a three-phase evolution in the past decade: from the PC-based operating system to an embedded operating system to the current smart phone-oriented operating system. The Mobile OS architecture has gone from simple to complex to something in-between, while this entire evolution process. This evolution process is driven naturally by the technology advancements in the internet, as well as in software and hardware because of the advancement in the custom software development companies.

The technological advancements by web development companies have resulted in a variety of different competing mobile operating system solutions on the market driven by different actors. Few of these actors include Bada by Samsung, iOS of Apple, Android by Google, RIM’s BlackBerry OS, Symbian of Nokia, Windows Phone by Microsoft, webOS by HP and few embedded Linux distributions such as MeeGo and Maemo to mention few of them.

Some of the most popular mobile operating systems are described below:

Android OS

As of 2011, Android has the largest installed base of any mobile OS and its devices also sell more than Windows, iOS and Mac OS devices combined as of 2013 (Mahapatra, 2013). As of July 2013 the Google Play store has had over 1 million Android apps published, and over 50 billion apps downloaded (PHONEARENA, 2014). One of the developer survey conducted between April and May 2013 found that 71% of mobile developers develop for Android (DEVECO, 2013).

The layers of Android platform are as follows :

• Linux Kernel: Android relies on Linux for core system services such as process management, security, memory management, and many more.

• Android Runtime: it provides a set of core libraries which supports most of the functionality in the core Java libraries. Android Virtual Machine known as Dalvik VM relies on the Linux kernel for some underlying functionality.

• Libraries: Android includes a set of C/C++ libraries which are exposed to developers through the Android application framework including surface manager, media libraries, system C libraries, 3D libraries etc.

• Application Framework: it provides an access layer to the framework APIs used by the core applications and allows components to be used by the developers

iOS

• iOS(previously iPhone OS) is a mobile operating system developed by Apple Inc. and  is exclusively distributed for Apple hardware. iOS is the operating system that powers iPod Touch, iPad, Apple TV and iPhone. It promoted a new style of user interaction for limited input devices, small screen, specifically, direct manipulation. On-screen interface elements, and to perform interface operations are controlled by touch-based gestures like tap and hold, tap, swipe, and pinch. iOS is derived from Mac OS X.

iOS is made up of following  abstraction layers:

• Core OS: The kernel of the operating system including basic low-level features: system support—DNS, threads, math, sockets, memory—general security services— private/public keys, certificates, encryption— Bluetooth, sound and image processing, and external hardware management.

• Core Services: Fundamental system-services, which are subdivided in different frameworks and based on C and Objective C. IT include basic application services including SQLite, calendar events, XML support, accounts, location data management, contacts, networking,  and store purchasing. 

• Media Layer: Considers the high-level frameworks that are responsible for using graphics both 2d and 3d, video- and audio technologies.

• Cocoa Touch: The UIKIT, which is an Objective- C based framework and provides a number of functionalities that are necessary for the development of an iOS Application like the User Interface Management. Also APIs for building applications— multitasking, notifications, interface views, access to device data and touch input are included. 

Windows Phone

Windows Phone is a proprietary smart phone operating system developed by Microsoft. It is the successor to Windows Mobile, though it is incompatible with the earlier platform. Windows Phone was launched in 2010 under the name Windows Phone 7. Large number of hardware manufacturers including HTC, Samsung, LG, and Nokia are developing Windows Phone devices. Both Nokia and Microsoft announced in February 2011 that Windows Phone 7 would be the primary OS for all future Nokia smart phones. Windows Phone 7 received a major upgrade (7.5 Mango) in February 2011, adding features that had been missing in the original release. The Second generation Windows Phone 8 was released in October 2012 (NCSU, 2014).

Windows Phone 7’s architecture required a hardware layer that meets Microsoft’s minimum system requirements: a multi-touch capacitive display, 256MB RAM, a DirectX 9-capable GPU, an accelerometer, 8GB of flash memory, a compass, a 5-megapixel camera, proximity and light sensors, an A-GPS, an ARM7 CPU and six physical buttons: back, start, and search; camera, volume, and power/sleep(Windows, 2011). Windows Phone kernel handles low-level device driver access as well as basic storage, security and networking.Three libraries: a UI model for user-interface management, an App Model for application management, and a Cloud Integration module for web search via push notifications, location services ,Bing, and so on sit above the kernel (NCSU, 2014). The application-facing APIs include XNA, Silverlight, HTML/JavaScript and the Common Language Runtime (CLR) that supports C# or VB .Net applications. Kernel itself is a proprietary Windows OS design for embedded devices that combines Windows Embedded CE 6.0 R3 and Windows Embedded Compact 77. Windows Phone 8 replaced the Windows CE kernel with one based on Windows NT and this is meant in part to mimic the Windows 8 desktop OS, which allows for easier porting of applications between the two operating systems, usually carried out in many application development companies.

Author Signature - Sanika Taori