A program may not be sufficiently complete for execution by a computer. In particular, it may require additional software from a software library in order to be complete. Such a library may include software components used by stand-alone programs, but which cannot work on their own. Thus, programs may include standard routines that are common to many programs, extracted from these libraries. Libraries may also include 'stand-alone' programs which are activated by some computer event and/or perform some function (e.g., of computer 'housekeeping') but do not return data to their calling program. Programs may be called by one to many other programs; programs may call zero to many other programs.
Three layers
Users often see things differently than programmers. People who use modern general purpose computers (as opposed to embedded systems, analog computers, supercomputers, etc.) usually see three layers of software performing a variety of tasks: platform, application, and user software.
Platform software
Platform includes the basic input-output system (often described as firmware rather than software), device drivers, an operating system, and typically a graphical user interface which, in total, allow a user to interact with the computer and its peripherals (associated equipment). Platform software often comes bundled with the computer, and users may not realize that it exists or that they have a choice to use different platform software.
Application software
Application software or Applications are what most people think of when they think of software. Typical examples include office suites and video games. Application software is often purchased separately from computer hardware. Sometimes applications are bundled with the computer, but that does not change the fact that they run as independent applications. Applications are almost always independent programs from the operating system, though they are often tailored for specific platforms. Most users think of compilers, databases, and other "system software" as applications.
User-written software User software tailors systems to meet the users specific needs. User software include spreadsheet templates, word processor macros, scientific simulations, graphics and animation scripts. Even email filters are a kind of user software. Users create this software themselves and often overlook how important it is. Depending on how competently the user-written software has been integrated into purchased application packages, many users may not be aware of the distinction between the purchased packages, and what has been added by fellow co-workers
Thursday, March 29, 2007
Software development
Software development is the translation of a user need or marketing goal into a software product Software development is sometimes understood to encompass the processes of software engineering combined with the research and goals of software marketing to develop computer software products
Software design
Software design is a process of problem-solving and planning for a software solution. After the purpose and specifications of software is determined, software developers will design or employ designers to develop a plan for a solution.
Software, consisting of programs, enables a computer to perform specific tasks, as opposed to the physical components of the system (hardware). This includes application software such as a word processor, which enables a user to perform a task, and system software such as an operating system, which enables other software to run properly, by interfacing with hardware and with other software or custom software made to user specifications.
Software design
Software design is a process of problem-solving and planning for a software solution. After the purpose and specifications of software is determined, software developers will design or employ designers to develop a plan for a solution.
Software, consisting of programs, enables a computer to perform specific tasks, as opposed to the physical components of the system (hardware). This includes application software such as a word processor, which enables a user to perform a task, and system software such as an operating system, which enables other software to run properly, by interfacing with hardware and with other software or custom software made to user specifications.
Wednesday, March 14, 2007
Operating System
An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. An operating system rationally processes electronic devices in response to approved commands. At the foundation of all system software, an operating system performs basic tasks such as controlling and allocating memory, prioritizing system requests, controlling input and output devices, facilitating networking, and managing files. Most operating systems have a command line interpreter as a basic user interface, but they may also provide a graphical user interface (GUI) for higher level functions. The operating system forms a platform for other system software and for application software.
Process management
Every program running on a computer, be it background services or applications, is a process.
As long as a von Neumann architecture is used to build computers, only one process per CPU can be run at a time. Older microcomputer OS such as MS-DOS did not attempt to bypass this limit, with the exception of interrupt processing, and only one process could be run under them (although DOS itself featured TSR as a very partial and not too easy to use solution). Mainframe operating systems have had multitasking capabilities since the early 1960s. Modern operating systems enable concurrent execution of many processes at once via multitasking even with one CPU. Process management is an operating system's way of dealing with running multiple processes. Since most computers contain one processor with one core, multitasking is done by simply switching processes quickly. Depending on the operating system, as more processes run, either each time slice will become smaller or there will be a longer delay before each process is given a chance to run. Process management involves computing and distributing CPU time as well as other resources. Most operating systems allow a process to be assigned a priority which affects its allocation of CPU time. Interactive operating systems also employ some level of feedback in which the task with which the user is working receives higher priority. Interrupt driven processes will normally run at a very high priority. In many systems there is a background process, such as the System Idle Process in Windows, which will run when no other process is waiting for the CPU.
Memory management
Current computer architectures arrange the computer's memory in a hierarchical manner, starting from the fastest registers, CPU cache, random access memory and disk storage. An operating system's memory manager coordinates the use of these various types of memory by tracking which one is available, which is to be allocated or deallocated and how to move data between them. This activity, usually referred to as virtual memory management, increases the amount of memory available for each process by making the disk storage seem like main memory. There is a speed penalty associated with using disks or other slower storage as memory – if running processes require significantly more RAM than is available, the system may start thrashing. This can happen either because one process requires a large amount of RAM or because two or more processes compete for a larger amount of memory than is available. This then leads to constant transfer of each process's data to slower storage.
Another important part of memory management is managing virtual addresses. If multiple processes are in memory at once, they must be prevented from interfering with each other's memory (unless there is an explicit request to utilise shared memory). This is achieved by having separate address spaces. Each process sees the whole virtual address space, typically from address 0 up to the maximum size of virtual memory, as uniquely assigned to it. The operating system maintains a page table that match virtual addresses to physical addresses. These memory allocations are tracked so that when a process terminates, all memory used by that process can be made available for other processes.
The operating system can also write inactive memory pages to secondary storage. This process is called "paging" or "swapping" – the terminology varies between operating systems.
It is also typical for operating systems to employ otherwise unused physical memory as a page cache; requests for data from a slower device can be retained in memory to improve performance. The operating system can also pre-load the in-memory cache with data that may be requested by the user in the near future; SuperFetch is an example of this.
Disk and file systems
All operating systems include support for a variety of file systems.
Modern file systems are comprised of a hierarchy of directories. While the idea is conceptually similar across all general-purpose file systems, some differences in implementation exist. Two noticeable examples of this are the character used to separate directories, and case sensitivity. By default, Microsoft Windows demarcates its path components with a backslash (Japanese editions of Windows use ¥, and Korean editions use ₩) and its file names are not case sensitive. whereas Unix/Linux-derived operating systems, as well as Amiga OS and Mac OS X, use the forward slash and their file names generally are case sensitive. Versions of Mac OS prior to OS X use a colon for a path separator. RISC OS uses a period.
File systems are journaled or non-journaled. A journaled file system is a safer alternative under the circumstances of a system crash. If a system comes to an abrupt stop in a system crash scenario, the non-journaled system will need to undergo an examination from the system check utilities, whereas the journaled file systems recovery is automatic.
Many Linux distributions support some or all of ext2, ext3, ReiserFS, Reiser4, GFS, GFS2, OCFS, OCFS2, NILFS. Linux also has full support for XFS and JFS, along with the FAT file systems, and NTFS.
Microsoft Windows includes support for FAT12, FAT16, FAT32, and NTFS. The NTFS file system is the most efficient and reliable of the four Windows systems, and as of Windows Vista, is the only file system which the operating system can be installed on. Windows Embedded CE 6.0 introduced ExFAT, a file system suitable for flash drives
Mac OS X supports HFS+ as its primary file system, and it supports several other file systems as well.
Common to all these (and other) operating systems is support for file systems typically found on removable media. FAT12 is the file system most commonly found on floppy discs. ISO 9660 and Universal Disk Format are two common formats that target Compact Discs and DVDs, respectively. Mount Rainier is a newer extension to UDF supported by Linux 2.6 kernels and Windows Vista that facilitates rewriting to DVDs in the same fashion as what has been possible with floppy disks.
Networking
Most current operating systems are capable of using the TCP/IP networking protocols. This means that one system can appear on a network of the other and share resources such as files, printers, and scanners using either wired or wireless connections.
Many operating systems also support one or more vendor-specific legacy networking protocols as well, for example, SNA on IBM systems, DECnet on systems from Digital Equipment Corporation, and Microsoft-specific protocols on Windows. Specific protocols for specific tasks may also be supported such as NFS for file access.
Security
Many operating systems include some level of security. Security is based on the two ideas that:
The operating system provides access to a number of resources, directly or indirectly, such as files on a local disk, privileged system calls, personal information about users, and the services offered by the programs running on the system;
The operating system is capable of distinguishing between some requesters of these resources who are authorized (allowed) to access the resource, and others who are not authorized (forbidden). While some systems may simply distinguish between "privileged" and "non-privileged", systems commonly have a form of requester identity, such as a user name. Requesters, in turn, divide into two categories:
Internal security: an already running program. On some systems, a program once it is running has no limitations, but commonly the program has an identity which it keeps and is used to check all of its requests for resources.
External security: a new request from outside the computer, such as a login at a connected console or some kind of network connection. To establish identity there may be a process of authentication. Often a username must be quoted, and each username may have a password. Other methods of authentication, such as magnetic cards or biometric data might be used instead. In some cases, especially connections from the network, resources may be accessed with no authentication at all.
In addition, to the allow/disallow model of security, a system with a high level of security will also offer auditing options. These would allow tracking of requests for access to resources (such as, "who has been reading this file?").
Security of operating systems has long been a concern because of highly sensitive data held on computers, both of a commercial and military nature. The United States Government Department of Defense (DoD) created the Trusted Computer System Evaluation Criteria (TCSEC), which is a standard that sets basic requirements for assessing the effectiveness of security. This became of vital importance to operating system makers, because the TCSEC was used to evaluate, classify and select computer systems being considered for the processing, storage and retrieval of sensitive or classified information.
Internal security
Internal security can be thought of as protecting the computer's resources from the programs concurrently running on the system. Most operating systems set programs running natively on the computer's processor, so the problem arises of how to stop these programs doing the same task and having the same privileges as the operating system (which is after all just a program too). Processors used for general purpose operating systems generally have a hardware concept of privilege. Generally less privileged programs are automatically blocked from using certain hardware instructions, such as those to read or write from external devices like disks. Instead, they have to ask the privileged program (operating system kernel) to read or write. The operating system therefore gets the chance to check the program's identity and allow or refuse the request.
An alternative strategy, and the only sandbox strategy available in systems that do not meet the Popek and Goldberg virtualization requirements, is the operating system not running user programs as native code, but instead either emulates a processor or provides a host for a p-code based system such as Java.
Internal security is especially relevant for multi-user systems; it allows each user of the system to have private files that the other users cannot tamper with or read. Internal security is also vital if auditing is to be of any use, since a program can potentially bypass the operating system, inclusive of bypassing auditing.
External security
Typically an operating system offers (hosts) various services to other network computers and users. These services are usually provided through ports or numbered access points beyond the operating systems network address. Typically services include offerings such as file sharing, print services, email, web sites, and file transfer protocols.
At the front line of security are hardware devices known as firewalls. At the operating system level, there are a number of software firewalls available. Most modern operating systems include a software firewall, which is enabled by default. A software firewall can be configured to allow or deny network traffic to or from a service or application running on the operating system. Therefore, one can install and be running an insecure service, such as Telnet or FTP, and not have to be threatened by a security breach because the firewall would deny all traffic trying to connect to the service on that port.
Graphical user interfaces
Today, most modern operating systems contain Graphical User Interfaces (GUIs, pronounced goo-eez). A few older operating systems tightly integrated the GUI to the kernel—for example, the original implementations of Microsoft Windows and Mac OS. More modern operating systems are modular, separating the graphics subsystem from the kernel (as is now done in Linux, and Mac OS X, and to a limited extent Windows).
Many operating systems allow the user to install or create any user interface they desire. The X Window System in conjunction with GNOME or KDE is a commonly found setup on most Unix and Unix derivative (BSD, Linux, Minix) systems.
Graphical user interfaces tend to change and evolve over time. For example, Windows has modified its user interface almost every time a new major version of Windows is released, and the Mac OS GUI changed dramatically with the introduction of Mac OS X in 2001.
Device drivers
A device driver is a specific type of computer software developed to allow interaction with hardware devices. Typically this constitutes an interface for communicating with the device, through the specific computer bus or communications subsystem that the hardware is connected to, providing commands to and/or receiving data from the device, and on the other end, the requisite interfaces to the operating system and software applications. It is a specialized hardware-dependent computer program which is also operating system specific that enables another program, typically an operating system or applications software package or computer program running under the operating system kernel, to interact transparently with a hardware device, and usually provides the requisite interrupt handling necessary for any necessary asynchronous time-dependent hardware interfacing needs.
The key design goal of device drivers is abstraction. Every model of hardware (even within the same class of device) is different. Newer models also are released by manufacturers that provide more reliable or better performance and these newer models are often controlled differently. Computers and their operating systems cannot be expected to know how to control every device, both now and in the future. To solve this problem, OSes essentially dictate how every type of device should be controlled. The function of the device driver is then to translate these OS mandated function calls into device specific calls. In theory a new device, which is controlled in a new manner, should function correctly if a suitable driver is available. This new driver will ensure that the device appears to operate as usual from the operating systems' point of view for any person.
Process management
Every program running on a computer, be it background services or applications, is a process.
As long as a von Neumann architecture is used to build computers, only one process per CPU can be run at a time. Older microcomputer OS such as MS-DOS did not attempt to bypass this limit, with the exception of interrupt processing, and only one process could be run under them (although DOS itself featured TSR as a very partial and not too easy to use solution). Mainframe operating systems have had multitasking capabilities since the early 1960s. Modern operating systems enable concurrent execution of many processes at once via multitasking even with one CPU. Process management is an operating system's way of dealing with running multiple processes. Since most computers contain one processor with one core, multitasking is done by simply switching processes quickly. Depending on the operating system, as more processes run, either each time slice will become smaller or there will be a longer delay before each process is given a chance to run. Process management involves computing and distributing CPU time as well as other resources. Most operating systems allow a process to be assigned a priority which affects its allocation of CPU time. Interactive operating systems also employ some level of feedback in which the task with which the user is working receives higher priority. Interrupt driven processes will normally run at a very high priority. In many systems there is a background process, such as the System Idle Process in Windows, which will run when no other process is waiting for the CPU.
Memory management
Current computer architectures arrange the computer's memory in a hierarchical manner, starting from the fastest registers, CPU cache, random access memory and disk storage. An operating system's memory manager coordinates the use of these various types of memory by tracking which one is available, which is to be allocated or deallocated and how to move data between them. This activity, usually referred to as virtual memory management, increases the amount of memory available for each process by making the disk storage seem like main memory. There is a speed penalty associated with using disks or other slower storage as memory – if running processes require significantly more RAM than is available, the system may start thrashing. This can happen either because one process requires a large amount of RAM or because two or more processes compete for a larger amount of memory than is available. This then leads to constant transfer of each process's data to slower storage.
Another important part of memory management is managing virtual addresses. If multiple processes are in memory at once, they must be prevented from interfering with each other's memory (unless there is an explicit request to utilise shared memory). This is achieved by having separate address spaces. Each process sees the whole virtual address space, typically from address 0 up to the maximum size of virtual memory, as uniquely assigned to it. The operating system maintains a page table that match virtual addresses to physical addresses. These memory allocations are tracked so that when a process terminates, all memory used by that process can be made available for other processes.
The operating system can also write inactive memory pages to secondary storage. This process is called "paging" or "swapping" – the terminology varies between operating systems.
It is also typical for operating systems to employ otherwise unused physical memory as a page cache; requests for data from a slower device can be retained in memory to improve performance. The operating system can also pre-load the in-memory cache with data that may be requested by the user in the near future; SuperFetch is an example of this.
Disk and file systems
All operating systems include support for a variety of file systems.
Modern file systems are comprised of a hierarchy of directories. While the idea is conceptually similar across all general-purpose file systems, some differences in implementation exist. Two noticeable examples of this are the character used to separate directories, and case sensitivity. By default, Microsoft Windows demarcates its path components with a backslash (Japanese editions of Windows use ¥, and Korean editions use ₩) and its file names are not case sensitive. whereas Unix/Linux-derived operating systems, as well as Amiga OS and Mac OS X, use the forward slash and their file names generally are case sensitive. Versions of Mac OS prior to OS X use a colon for a path separator. RISC OS uses a period.
File systems are journaled or non-journaled. A journaled file system is a safer alternative under the circumstances of a system crash. If a system comes to an abrupt stop in a system crash scenario, the non-journaled system will need to undergo an examination from the system check utilities, whereas the journaled file systems recovery is automatic.
Many Linux distributions support some or all of ext2, ext3, ReiserFS, Reiser4, GFS, GFS2, OCFS, OCFS2, NILFS. Linux also has full support for XFS and JFS, along with the FAT file systems, and NTFS.
Microsoft Windows includes support for FAT12, FAT16, FAT32, and NTFS. The NTFS file system is the most efficient and reliable of the four Windows systems, and as of Windows Vista, is the only file system which the operating system can be installed on. Windows Embedded CE 6.0 introduced ExFAT, a file system suitable for flash drives
Mac OS X supports HFS+ as its primary file system, and it supports several other file systems as well.
Common to all these (and other) operating systems is support for file systems typically found on removable media. FAT12 is the file system most commonly found on floppy discs. ISO 9660 and Universal Disk Format are two common formats that target Compact Discs and DVDs, respectively. Mount Rainier is a newer extension to UDF supported by Linux 2.6 kernels and Windows Vista that facilitates rewriting to DVDs in the same fashion as what has been possible with floppy disks.
Networking
Most current operating systems are capable of using the TCP/IP networking protocols. This means that one system can appear on a network of the other and share resources such as files, printers, and scanners using either wired or wireless connections.
Many operating systems also support one or more vendor-specific legacy networking protocols as well, for example, SNA on IBM systems, DECnet on systems from Digital Equipment Corporation, and Microsoft-specific protocols on Windows. Specific protocols for specific tasks may also be supported such as NFS for file access.
Security
Many operating systems include some level of security. Security is based on the two ideas that:
The operating system provides access to a number of resources, directly or indirectly, such as files on a local disk, privileged system calls, personal information about users, and the services offered by the programs running on the system;
The operating system is capable of distinguishing between some requesters of these resources who are authorized (allowed) to access the resource, and others who are not authorized (forbidden). While some systems may simply distinguish between "privileged" and "non-privileged", systems commonly have a form of requester identity, such as a user name. Requesters, in turn, divide into two categories:
Internal security: an already running program. On some systems, a program once it is running has no limitations, but commonly the program has an identity which it keeps and is used to check all of its requests for resources.
External security: a new request from outside the computer, such as a login at a connected console or some kind of network connection. To establish identity there may be a process of authentication. Often a username must be quoted, and each username may have a password. Other methods of authentication, such as magnetic cards or biometric data might be used instead. In some cases, especially connections from the network, resources may be accessed with no authentication at all.
In addition, to the allow/disallow model of security, a system with a high level of security will also offer auditing options. These would allow tracking of requests for access to resources (such as, "who has been reading this file?").
Security of operating systems has long been a concern because of highly sensitive data held on computers, both of a commercial and military nature. The United States Government Department of Defense (DoD) created the Trusted Computer System Evaluation Criteria (TCSEC), which is a standard that sets basic requirements for assessing the effectiveness of security. This became of vital importance to operating system makers, because the TCSEC was used to evaluate, classify and select computer systems being considered for the processing, storage and retrieval of sensitive or classified information.
Internal security
Internal security can be thought of as protecting the computer's resources from the programs concurrently running on the system. Most operating systems set programs running natively on the computer's processor, so the problem arises of how to stop these programs doing the same task and having the same privileges as the operating system (which is after all just a program too). Processors used for general purpose operating systems generally have a hardware concept of privilege. Generally less privileged programs are automatically blocked from using certain hardware instructions, such as those to read or write from external devices like disks. Instead, they have to ask the privileged program (operating system kernel) to read or write. The operating system therefore gets the chance to check the program's identity and allow or refuse the request.
An alternative strategy, and the only sandbox strategy available in systems that do not meet the Popek and Goldberg virtualization requirements, is the operating system not running user programs as native code, but instead either emulates a processor or provides a host for a p-code based system such as Java.
Internal security is especially relevant for multi-user systems; it allows each user of the system to have private files that the other users cannot tamper with or read. Internal security is also vital if auditing is to be of any use, since a program can potentially bypass the operating system, inclusive of bypassing auditing.
External security
Typically an operating system offers (hosts) various services to other network computers and users. These services are usually provided through ports or numbered access points beyond the operating systems network address. Typically services include offerings such as file sharing, print services, email, web sites, and file transfer protocols.
At the front line of security are hardware devices known as firewalls. At the operating system level, there are a number of software firewalls available. Most modern operating systems include a software firewall, which is enabled by default. A software firewall can be configured to allow or deny network traffic to or from a service or application running on the operating system. Therefore, one can install and be running an insecure service, such as Telnet or FTP, and not have to be threatened by a security breach because the firewall would deny all traffic trying to connect to the service on that port.
Graphical user interfaces
Today, most modern operating systems contain Graphical User Interfaces (GUIs, pronounced goo-eez). A few older operating systems tightly integrated the GUI to the kernel—for example, the original implementations of Microsoft Windows and Mac OS. More modern operating systems are modular, separating the graphics subsystem from the kernel (as is now done in Linux, and Mac OS X, and to a limited extent Windows).
Many operating systems allow the user to install or create any user interface they desire. The X Window System in conjunction with GNOME or KDE is a commonly found setup on most Unix and Unix derivative (BSD, Linux, Minix) systems.
Graphical user interfaces tend to change and evolve over time. For example, Windows has modified its user interface almost every time a new major version of Windows is released, and the Mac OS GUI changed dramatically with the introduction of Mac OS X in 2001.
Device drivers
A device driver is a specific type of computer software developed to allow interaction with hardware devices. Typically this constitutes an interface for communicating with the device, through the specific computer bus or communications subsystem that the hardware is connected to, providing commands to and/or receiving data from the device, and on the other end, the requisite interfaces to the operating system and software applications. It is a specialized hardware-dependent computer program which is also operating system specific that enables another program, typically an operating system or applications software package or computer program running under the operating system kernel, to interact transparently with a hardware device, and usually provides the requisite interrupt handling necessary for any necessary asynchronous time-dependent hardware interfacing needs.
The key design goal of device drivers is abstraction. Every model of hardware (even within the same class of device) is different. Newer models also are released by manufacturers that provide more reliable or better performance and these newer models are often controlled differently. Computers and their operating systems cannot be expected to know how to control every device, both now and in the future. To solve this problem, OSes essentially dictate how every type of device should be controlled. The function of the device driver is then to translate these OS mandated function calls into device specific calls. In theory a new device, which is controlled in a new manner, should function correctly if a suitable driver is available. This new driver will ensure that the device appears to operate as usual from the operating systems' point of view for any person.
computer Network
Networking is a complex part of computing that makes up most of the IT Industry. Without networks, almost all communication in the world would cease to happen. It is because of networking that telephones, televisions, the internet, etc. work.
There are two (broad) types of networks in existence at the moment. These are:
Local Area Network (LAN)
A Local Area Network is a network that spans a relatively small space and provides services to a small amount of people. Depending on the amount of people that use a Local Area Network, a peer-to-peer or client-server method of networking may be used. A peer-to-peer network is where each client shares their resources with other workstations in the network. Examples of peer-to-peer networks are: Small office networks where resource use is minimal and a home network. A client-server network is where every client is connected to the server and each other. Client-server networks use servers in different capacities. These can be classified into two types: Single-service servers, where the server performs one task such as file server, print server, etc.; while other servers can not only perform in the capacity of file servers and print servers, but they also conduct calculations and use these to provide information to clients (Web/Intranet Server). Computers are linked via Ethernet Cable, can be joined either directly (one computer to another), or via a network hub that allows multiple connections.
Wide Area Network (WAN)
A Wide Area Network is a network where a wide variety of resources are deployed across a large domestic area or internationally. An example of this is a multinational business that uses a WAN to interconnect their offices in different countries. The largest and best example of a WAN is the Internet, which is the largest network in the world.
In order for communication to take place between computers, mediums must be used. These mediums include Protocols, Physical Routers and Ethernet, etc. This is covered by Open Systems Interconnection which comprises all the processes that make information transport possible.
These different networking methods make data communication possible in many different situations and provide an internationally accepted standard through which all computer networking is built upon.
There are two (broad) types of networks in existence at the moment. These are:
Local Area Network (LAN)
A Local Area Network is a network that spans a relatively small space and provides services to a small amount of people. Depending on the amount of people that use a Local Area Network, a peer-to-peer or client-server method of networking may be used. A peer-to-peer network is where each client shares their resources with other workstations in the network. Examples of peer-to-peer networks are: Small office networks where resource use is minimal and a home network. A client-server network is where every client is connected to the server and each other. Client-server networks use servers in different capacities. These can be classified into two types: Single-service servers, where the server performs one task such as file server, print server, etc.; while other servers can not only perform in the capacity of file servers and print servers, but they also conduct calculations and use these to provide information to clients (Web/Intranet Server). Computers are linked via Ethernet Cable, can be joined either directly (one computer to another), or via a network hub that allows multiple connections.
Wide Area Network (WAN)
A Wide Area Network is a network where a wide variety of resources are deployed across a large domestic area or internationally. An example of this is a multinational business that uses a WAN to interconnect their offices in different countries. The largest and best example of a WAN is the Internet, which is the largest network in the world.
In order for communication to take place between computers, mediums must be used. These mediums include Protocols, Physical Routers and Ethernet, etc. This is covered by Open Systems Interconnection which comprises all the processes that make information transport possible.
These different networking methods make data communication possible in many different situations and provide an internationally accepted standard through which all computer networking is built upon.
Helps
This article helps you ask the right questions of a business broadband provider so that you too can enjoy low contention rates, fast network access, reliable service and a friendly voice to help assist you in your business broadband related issues.
There are many companies who have already adopted broadband as a technology in their business today - it is now widely used to access the internet, send and receive email, network offices, provide access to web servers... the list goes on...
Interestingly many of the decisions that companies have made regarding a business broadband provider were made simply on cost, locality and brand. Often overlooked are the core issues that differentiate whether your business broadband provider is high-performance or not.
This article helps you ask the right questions of a business broadband provider so that you too can enjoy low contention rates, fast network access, reliable service and a friendly voice to help assist you in your business broadband related issues.
The business broadband provider you use will critically impact your business and the standard of service you offer to your customers. The quality of your business broadband also has a direct effect on staff productivity and even effects morale in the business.
Value in a business broadband service isn-t just defined by the price - buy cheap and expect low quality, poor resilience and email only support or at best very long time to wait for telephone support.
Example questions that you can ask your current business broadband supplier or prospective business broadband supplier include:
* Does the business broadband provider offer a guarenteed level of service?
* Does the business broadband provider focus on high-performance connectivity?
* Can the provider offer added services such as voice over IP, bonded broadband and
* What is the business broadband provider-s network contention policy? Be careful of any more than 5:1!
* Do they have a technical support service and how fast do they answer the phone? You don-t want to be on hold for long periods of time 15mins+
* You should ask your business broadband provider for client references.
* What level of after-sales and technical support does the business broadband provider offer - will you be speaking to a qualified professional - will they provide you with personal dedicated support?
* Do they provide you with value for money when compared to competitor services?
Nathan Hill-Haimes
Managed Communications is a high-performance Managed VPN Service provider - the company does not use the public internet to create VPNs as experience has shown this is where many issues regarding latency and security can occur. In addition to standard VPN services bonding of lines enables higher capacity than other service providers can offer to key VPN sites.
Managed Communications - www.managedcomms.co.uk
Managed network
Leased line
DSL MAX
Managed VPN
Business ADSL
Business SDSL
VOIP network
VOIP VPN
Bonded SDSL
QOS DSL
There are many companies who have already adopted broadband as a technology in their business today - it is now widely used to access the internet, send and receive email, network offices, provide access to web servers... the list goes on...
Interestingly many of the decisions that companies have made regarding a business broadband provider were made simply on cost, locality and brand. Often overlooked are the core issues that differentiate whether your business broadband provider is high-performance or not.
This article helps you ask the right questions of a business broadband provider so that you too can enjoy low contention rates, fast network access, reliable service and a friendly voice to help assist you in your business broadband related issues.
The business broadband provider you use will critically impact your business and the standard of service you offer to your customers. The quality of your business broadband also has a direct effect on staff productivity and even effects morale in the business.
Value in a business broadband service isn-t just defined by the price - buy cheap and expect low quality, poor resilience and email only support or at best very long time to wait for telephone support.
Example questions that you can ask your current business broadband supplier or prospective business broadband supplier include:
* Does the business broadband provider offer a guarenteed level of service?
* Does the business broadband provider focus on high-performance connectivity?
* Can the provider offer added services such as voice over IP, bonded broadband and
* What is the business broadband provider-s network contention policy? Be careful of any more than 5:1!
* Do they have a technical support service and how fast do they answer the phone? You don-t want to be on hold for long periods of time 15mins+
* You should ask your business broadband provider for client references.
* What level of after-sales and technical support does the business broadband provider offer - will you be speaking to a qualified professional - will they provide you with personal dedicated support?
* Do they provide you with value for money when compared to competitor services?
Nathan Hill-Haimes
Managed Communications is a high-performance Managed VPN Service provider - the company does not use the public internet to create VPNs as experience has shown this is where many issues regarding latency and security can occur. In addition to standard VPN services bonding of lines enables higher capacity than other service providers can offer to key VPN sites.
Managed Communications - www.managedcomms.co.uk
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DSL MAX
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Business SDSL
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Link Popularity Tool
Link popularity tools are widely used by various webmasters to judge their internet presence. Even the web crawlers or search engines are using the effective popularity tools to measure the rankings of the various websites. You can also use the latest tools such as link popularity software, online optimizers and prowlers to boost up the page ranking of your website(s). By using these tools, you would certainly gain a greater number of targeted traffic as well as business contacts.
First of all lets us discuss the basics of link popularity. A website is always ranked on the basis of its link popularity. And link popularity is nothing but measuring the number of quality links on your website. Your website can support certain links—inbound outbound and reciprocal links— with other websites in the forms of text link, banners or advertisements. The more quality links you have, the more popular is your website. So, a good link popularity tool or software would drastically increase your page rank provided by the major search engines.
So using link popularity tool is a must for you these days. They help you increase the targeted traffic on your websites. The smart software are even capable of finding out the right links for you. The right links are the ones that are related to your website. For example: if you have a perfume website then the website providing information on perfumes will be made to link to your website by these software.
Apart from this, they also track your link popularity regularly. This further helps you take the apt steps for improving on your links and the top page rank do not seem far any more.
Links if placed properly can bring the most of the internet traffic to your website(s). But how can you find out which ones are the right software for you? Simply, pick a link popularity tool that helps you place your links at the proper places. These software are adept at finding out the websites with good page ranks for you. They find the websites that are related to your websites only. This means that no useless link will be added to your link directory and your link popularity will increase smoothly.
The more quality links you have on your website, the more traffic your site will find. The link popularity tools are one of the most important ways to improve your website ratings in the top search engines. In fact some technical experts hold the view that you should not imagine a good rating by the search engines without having a good network of links.
These tools are easy-to-install and can be installed on every type of operating systems.
Adding more to the benefits of these advanced tools, they can also help you link to your competitors. Some software in the market ensures you to link up with the best competitors in the market. After adding a link to the website, the link popularity tools automatically send an email for reciprocal link request.
You also get the complete reports of quality links with the help of these link popularity tools. You will get to know with whom you are having the links. This way, you can utilize the link popularity tools to enhance the performance of your website.
Link popularity tools are widely used by various webmasters to judge their internet presence. Even the web crawlers or search engines are using the effective popularity tools to measure the rankings of the various websites. You can also use the latest tools such as link popularity software, online optimizers and prowlers to boost up the page ranking of your website(s). By using these tools, you would certainly gain a greater number of targeted traffic as well as business contacts.
First of all lets us discuss the basics of link popularity. A website is always ranked on the basis of its link popularity. And link popularity is nothing but measuring the number of quality links on your website. Your website can support certain links—inbound outbound and reciprocal links— with other websites in the forms of text link, banners or advertisements. The more quality links you have, the more popular is your website. So, a good link popularity tool or software would drastically increase your page rank provided by the major search engines.
So using link popularity tool is a must for you these days. They help you increase the targeted traffic on your websites. The smart software are even capable of finding out the right links for you. The right links are the ones that are related to your website. For example: if you have a perfume website then the website providing information on perfumes will be made to link to your website by these software.
Apart from this, they also track your link popularity regularly. This further helps you take the apt steps for improving on your links and the top page rank do not seem far any more.
Links if placed properly can bring the most of the internet traffic to your website(s). But how can you find out which ones are the right software for you? Simply, pick a link popularity tool that helps you place your links at the proper places. These software are adept at finding out the websites with good page ranks for you. They find the websites that are related to your websites only. This means that no useless link will be added to your link directory and your link popularity will increase smoothly.
The more quality links you have on your website, the more traffic your site will find. The link popularity tools are one of the most important ways to improve your website ratings in the top search engines. In fact some technical experts hold the view that you should not imagine a good rating by the search engines without having a good network of links.
These tools are easy-to-install and can be installed on every type of operating systems.
Adding more to the benefits of these advanced tools, they can also help you link to your competitors. Some software in the market ensures you to link up with the best competitors in the market. After adding a link to the website, the link popularity tools automatically send an email for reciprocal link request.
You also get the complete reports of quality links with the help of these link popularity tools. You will get to know with whom you are having the links. This way, you can utilize the link popularity tools to enhance the performance of your website.
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