Monday, January 9, 2012

What is NGN

A Next-Generation Network (NGN) is the term given to describe a telecommunications packet-based network that handles multiple types of traffic (such as voice, data,  and multimedia). It is the convergence of  service provider networks that includes the public switched telephone network (PSTN), the data network (the Internet), and, in some instances, the wireless network as well.
* The NGN system offers key convergent multimedia services using a shared network characterized by several essential elements:
  • A unique and shared core network for all types of access and services.
  • A core network architecture divided into three layers: Transport, Control and Services.
  • Development of packet mode transport (IP flow transport in native IP, or on ATM in the short term with a progressive convergence to IP).
  • Open and standardized interfaces between each layer, and in particular for the Control and Services layers in order to allow third parties to develop and create services independent of the network.
  • Support for multiple applications (multimedia, real-time, transactional, total mobility) adaptable to the user and growing and varied capacities of access networks and terminals. * [Adapted from Moving towards the Next Generation Networks (NGN)]

Thursday, January 5, 2012

What is a Dual Core Processor

A dual core processor is a CPU with two separate cores on the same die, each with its own cache. It's the equivalent of getting two microprocessors in one.
In a single-core or traditional processor the CPU is fed strings of instructions it must order, execute, then selectively store in its cache for quick retrieval. When data outside the cache is required, it is retrieved through the system bus from random access memory (RAM) or from storage devices. Accessing these slows down performance to the maximum speed the bus, RAM or storage device will allow, which is far slower than the speed of the CPU. The situation is compounded when multi-tasking. In this case the processor must switch back and forth between two or more sets of data streams and programs. CPU resources are depleted and performance suffers.
In a dual core processor each core handles incoming data strings simultaneously to improve efficiency. Just as two heads are better than one, so are two hands. Now when one is executing the other can be accessing the system bus or executing its own code. Adding to this favorable scenario, both AMD and Intel's dual-core flagships are 64-bit.
To utilize a dual core processor, the operating system must be able to recognize multi-threading and the software must have simultaneous multi-threading technology (SMT) written into its code. SMT enables parallel multi-threading wherein the cores are served multi-threaded instructions in parallel. Without SMT the software will only recognize one core. Adobe® Photoshop® is an example of SMT-aware software. SMT is also used with multi-processor systems common to servers.
A dual core processor is different from a multi-processor system. In the latter there are two separate CPUs with their own resources. In the former, resources are shared and the cores reside on the same chip. A multi-processor system is faster than a system with a dual core processor, while a dual core system is faster than a single-core system, all else being equal.
An attractive value of dual core processors is that they do not require a new motherboard, but can be used in existing boards that feature the correct socket. For the average user the difference in performance will be most noticeable in multi-tasking until more software is SMT aware. Servers running multiple dual core processors will see an appreciable increase in performance.
Multi-core processors are the goal and as technology shrinks, there is more "real-estate" available on the die. In the fall of 2004 Bill Siu of Intel predicted that current accommodating motherboards would be here to stay until 4-core CPUs eventually force a changeover to incorporate a new memory controller that will be required for handling 4 or more cores.

What is a Computer Virus

A Computer Virus is a relatively small software program that is attached to another larger program for the purpose of gaining access to information or to corrupt information within a computer system. Some computer viruses may be relatively harmless. For example, some of them just cause a certain message to pop up on a user's computer screen. Other viruses can be deadly to the computers they infect, erasing information and hard drives, stealing data, and slowing down the entire computer system. Like other software programs, someone must create and write a computer virus; once they are created, viruses can multiply rapidly and spread themselves from computer to computer.

Computer Virus Definition & Characteristics:

A Computer Virus is a program that can copy itself and infect a computer without the permission or knowledge of the user. A computer virus has 2 major characteristics: the ability to replicate itself, and the ability to attach itself to another computer file. Every file or program that becomes infected can also act as a virus itself, allowing it to spread to other files and computers. The term "computer virus" is often used incorrectly as a catch-all phrase to include all types of Malware such as Computer Worms, Trojan Horses, Spyware, Adware, and Rootkits - all of which are slightly different than Computer Viruses.

A computer virus needs another program in order to be able to be activated and infect other computers files. Essentially, a computer virus rides piggyback on another file into your computer - once it is executed, the virus will continue to replicate and attach itself to other program files and continue to spread.

A Brief History of Computer Viruses:

Although computer scientists were aware of the theoretical possibility of computer viruses for decades, it was not until the 1980s that viruses began to gain a hold and multiply in large numbers. With the advent of the personal computer, floppy disk drives, and other portable information storage devices, it became easier to program and transfer viruses from one machine to another. Fred Cohen is often cited as the first person to use the term "computer virus" in an academic paper in 1984, although some suggest that he may have learned it from his mentor Leonard Adleman

Does My Computer Have a Virus?

Of course, if you ask anyone the question “what is a Computer Virus?”, the reply is likely going to be a bit jumbled. There are many different forms of computer viruses, although many have the same goal; to slow the infected computer system, steal and/or copy information from the computer, and attach itself to sent files and attachments in order to spread to other computer systems. The following are a few telltale signs that your computer might have a virus:
• Slow response and slow program execution
• Random hard drive crashes and restarts
• Distorted graphics and text
• Files that have mysteriously vanished
• Extensive pop-up ads
• Inability to open files with existing passwords
How Can I Protect My Computer from a Virus?

It is far better to avoid computer viruses and take proactive measures to protect your computer system than it is to clean up after them once they have gotten into your computer and caused damage. The following tips will help increase your odds of avoiding infection from a computer virus:
• Download programs only from trusted, reputable websites
• Install a quality Internet firewall
• Do Not open suspicious emails or email attachments
• MOST IMPORTANTLY — Make sure you have a trusted anti-virus program installed on your computer - such as Norton Antivirus, NOD32 Antivirus, or Kaspersky Antivirus.

Monday, January 2, 2012

What is Linux

A lot of the advantages of Linux are a consequence of Linux' origins, deeply rooted in UNIX, except for the first advantage, of course:
  • Linux is free:
    As in free beer, they say. If you want to spend absolutely nothing, you don't even have to pay the price of a CD. Linux can be downloaded in its entirety from the Internet completely for free. No registration fees, no costs per user, free updates, and freely available source code in case you want to change the behavior of your system.
    Most of all, Linux is free as in free speech:
    The license commonly used is the GNU Public License (GPL). The license says that anybody who may want to do so, has the right to change Linux and eventually to redistribute a changed version, on the one condition that the code is still available after redistribution. In practice, you are free to grab a kernel image, for instance to add support for teletransportation machines or time travel and sell your new code, as long as your customers can still have a copy of that code.
  • Linux is portable to any hardware platform:
    A vendor who wants to sell a new type of computer and who doesn't know what kind of OS his new machine will run (say the CPU in your car or washing machine), can take a Linux kernel and make it work on his hardware, because documentation related to this activity is freely available.
  • Linux was made to keep on running:
    As with UNIX, a Linux system expects to run without rebooting all the time. That is why a lot of tasks are being executed at night or scheduled automatically for other calm moments, resulting in higher availability during busier periods and a more balanced use of the hardware. This property allows for Linux to be applicable also in environments where people don't have the time or the possibility to control their systems night and day.
  • Linux is secure and versatile:
    The security model used in Linux is based on the UNIX idea of security, which is known to be robust and of proven quality. But Linux is not only fit for use as a fort against enemy attacks from the Internet: it will adapt equally to other situations, utilizing the same high standards for security. Your development machine or control station will be as secure as your firewall.
  • Linux is scalable:
    From a Palmtop with 2 MB of memory to a petabyte storage cluster with hundreds of nodes: add or remove the appropriate packages and Linux fits all. You don't need a supercomputer anymore, because you can use Linux to do big things using the building blocks provided with the system. If you want to do little things, such as making an operating system for an embedded processor or just recycling your old 486, Linux will do that as well.
  • The Linux OS and most Linux applications have very short debug-times:
    Because Linux has been developed and tested by thousands of people, both errors and people to fix them are usually found rather quickly. It sometimes happens that there are only a couple of hours between discovery and fixing of a bug. 

Wednesday, December 28, 2011

WIN 8

Microsoft is on a knife edge: It is developing a version of Windows that could ensure its continued success in the computer market — or it could completely cannibalize Microsoft’s profits and lead to the slow, painful, obsolescent death.
Windows 8, when you cut to the chase, is a tablet-oriented, touch-first skin on top of Windows 7. If you take into account the actual software stack and runtime, calling Metro a “skin” isn’t accurate at all, but as far as consumers and companies are concerned, that’s exactly what it is. There are two problems with this: First, if you already use Windows 7 — and hundreds of millions do — there is little reason to upgrade to Windows 8, much in the same way that everyone eschewed Vista and stuck with XP. Second, if everyone goes out and buys a Windows 8 tablet, Microsoft would collapse in a frothing fit of unprofitability.
You see, Windows 8 tablets, especially ARM variants, will be used almost exclusively in Metro mode — or, more accurately, tablet mode. At this point, Windows 8 ceases to be a “PC” operating system in the conventional sense of the word and enters a market that is dominated by Apple and Android and apps that cost between one and 10 dollars. On the desktop, Microsoft charges anywhere between $30 (OEMs) and $125 (retail box) for a Windows license, with the average being around $60. Android, by comparison, is free, and effectively so is iOS. A Microsoft Office license is even more costly, with an average price in the hundreds of dollars region. Mobile word processing apps like the iWork suite or Documents To Go, by comparison, cost just a few dollars.
Here’s the tricky bit: Microsoft has free or cheap alternatives to Windows and Office in the form of Windows Phone 7, Office Mobile, and Office Web Apps. For around $15, OEMs can license an operating system that has all of the major mobile computing components and is a direct analog of the cross-platform iOS — but it can only be used on smartphones. To put this into perspective, though, remember that Microsoft gets around $15 per smartphone, or between $30 and $300 per desktop or laptop. If we look at Microsoft’s 2011 profits of $23 billion, 57% came from its Windows division (Desktop & Server) and 65% from Business (Office) (The totals come to 122% because of internal adjustments, and because Bing currently loses more than a billion dollars per year.) Windows Phone 7 and Xbox are flecks of crud on Ballmer’s heel in comparison.
Microsoft, then, simply can’t afford to put Windows Phone 7 on its tablet “PCs.” If, during the next upgrade cycle, hundreds of millions of people bought WP7 tablets instead of Windows 8 tablets, Microsoft would lose billions of dollars and eventually go out of business. Microsoft is stuck between a rock and a hard place: It needs to be a serious competitor in the tablet market, but it simply can’t compete with Apple and Android in terms of cost, a problem that is exacerbated by Apple’s profits deriving from hardware rather than software. Remember the HP TouchPad? It was fatter, slower, and heavier than the iPad — but cost more. Windows 8 tablets, even if Microsoft cuts the margins on its cash cow franchises, cannot compete with iOS or Android on price — it’s as simple as that.
Fortunately, at least if you’re a Microsoft fan, there is a way out of this razor-sharp dichotomy. One method is for Microsoft to stick to its guns and call these Windows 8 tablets — whether they’re x86 or ARM — PCs. The inexorable cost difference between Windows 8 tablets and the competition will be ameliorated by the sheer awesomeness of being able to do anything with a portable slate. This is the route that Microsoft is currently taking, and given Ballmer’s painstakingly conservative efforts to milk Office and Windows for as long as possible it’s really the only feasible path.
There’s another option, though; one that would scare MS shareholders and the industry itself into a shocked stupor. Microsoft could buy out Nokia and create a beautiful Windows Phone 7 tablet. With the hardware and software both in-house, MS could compete with Apple on cost and production values. Furthermore, Microsoft could give up on the Metrofied Start screen and focus on making Windows 8 a first-class desktop-and-laptop enterprise-oriented OS. There would be a dip in Windows and Office licenses as consumers shift from PCs to their WP7 tablets, but Microsoft could mitigate that by offering more subscriber services. Think of Xbox Live and Xbox TV, but on your WP7 tablet. Instead of paying $300 for an Office license, think of paying $5 per month for oodles of SkyDrive space and access to both offline and online Office suites.
After almost 30 years of thundering ahead in the same direction, it would take cajones the size of cantaloupes to rock the Windows revenue boat — but at the same time, going full steam ahead and squeakily stipulating that Windows 8 tablets are PCs dammit! is a risky ploy as well. After all, if there has ever been a time when the definition — and fate — of PC s in question, it is now.
he Windows 8 release date has been shrouded in a cloud of rumors. Most experts expect a late 2011 early 2012 release of the operating system. A recently leaked Windows 8 product cycle chart provides the answers needed to determine the release date of the next Windows OS by Microsoft.
You can take a look at the image here. The chart lists the planning, development and readiness product cycle of Windows 8 and related Microsoft products such as Internet Explorer 8, Windows Live Wave 4, Windows Live Wave 5 and Windows 7. It also lists major events.
Some events and products have already been held / released and it is possible to pinpoint the release date of Windows 8 by making the remaining calculations.
Here is what we know. Forum I and Forum II have been major events, the former held in December 2009, the latter in April 2010. The listing lists four additional event, Forum III to Forum VI. The next two events fall into the development phase of Windows 8, the remaining two into the readiness phase.
Internet Explorer 9 and Windows Live Wave 4 have either been announced with final dates (at least for the beta) or released already.
Forum II was held 4-5 months after Forum I. If we take this approach we can calculate the approximate month of the other four forums. This would mean between 16 to 20 months from April 2010 on which coincides perfectly with the projected late 2011 release date.
The Windows 8 beta should be released around June 2011 and the final release might even hit the stores at the same time that Windows 7 was released, which was October.
The Internet Explorer 9 product cycle confirms the findings. Microsoft has announced a beta release of Internet Explorer 9 for August 2010. This would be the same time that Forum III will be held, which is exactly four months after Forum II.
The chart may be a bit off since Windows Live Wave 4 was released in June. It could be that Microsoft has projected the Forum III conference for June / July instead.
Could also be that the chart is not 100% accurate and it can happen that development cycles need to be shifted, especially if major issues are encountered during development.
Still, we are pretty sure that Microsoft will release the beta of Windows 8 in or around June 2011 and the final release of the operating system in or around October 2011.
What’s your take on the chart? We are very interested in users who can provide us with additional information including Forum III to Forum VI dates.







cisco configuration 851 dhcp

Building configuration...

Current configuration : 3755 bytes
!
version 12.4
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname CISCO851
!
boot-start-marker
boot-end-marker
!
enable secret *************
!
no aaa new-model
!
resource policy
!
clock timezone il -2
clock save interval 8
ip subnet-zero
no ip dhcp use vrf connected
!
ip dhcp pool lan
   network 192.168.1.0 255.255.255.0
   dns-server 80.179.55.100 80.179.52.100
   default-router 192.168.1.1
!
ip dhcp pool 2
   host 192.168.1.100 255.255.255.0
   client-identifier 000000000000000
!
ip dhcp pool 1
   host 192.168.1.101 255.255.255.0
   client-identifier 00000000000
ip cef
ip vrf mishmish
!
no ip domain lookup
ip domain name cisco
ip ssh time-out 60
ip ssh authentication-retries 2
ip ssh version 2
!
password encryption aes
!
crypto pki trustpoint TP-self-signed-3944136632
 enrollment selfsigned
 subject-name cn=IOS-Self-Signed-Certificate-3944136632
 revocation-check none
 rsakeypair TP-self-signed-3944136632
!
!
interface FastEthernet0
!
interface FastEthernet1
 duplex half
 speed 10
!
interface FastEthernet2
 duplex full
 speed 100
!
interface FastEthernet3
!
interface FastEthernet4
 ip address dhcp
 ip nat outside
 ip virtual-reassembly
 duplex auto
 speed auto
!
interface Vlan1
 ip address 192.168.1.1 255.255.255.0
 ip nat inside
 ip virtual-reassembly
!
ip classless
ip route 0.0.0.0 0.0.0.0 dhcp
!
ip http server
ip http secure-server
ip nat inside source list 18 interface FastEthernet4 overload
ip nat inside source static tcp 192.168.1.3 8080 interface FastEthernet4 8080
ip nat inside source static tcp 192.168.1.2 81 interface FastEthernet4 81
ip nat inside source static tcp 192.168.1.150 1983 interface FastEthernet4 1983
!
access-list 18 permit 192.168.1.0 0.0.0.255
!
control-plane
!
banner motd ^C
no
^C
alias exec s sh ip int br
alias exec r sh run
alias exec t configure terminal
alias exec a sh arp
alias exec c sh clock
!
line con 0
 logging synchronous
 no modem enable
line aux 0
line vty 0 4
 password 7 **********
 logging synchronous
 login
 transport input all
!
scheduler max-task-time 5000
end

cisco configuration 831 adsl

Building configuration...

Current configuration : 1723 bytes
!
version 12.4
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname 831K_M
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$qngq$fGS9WZBR2mw6iHSeqioyW.
!
no aaa new-model
!
resource policy
!
clock timezone il 2
clock save interval 8
ip subnet-zero
!
!
no ip dhcp use vrf connected
!
ip dhcp pool lan
   network 10.0.0.0 255.255.255.0
   dns-server 80.179.55.100 80.179.52.100
   default-router 10.0.0.2
!
!
ip cef
no ip domain lookup
no ip ips deny-action ips-interface
!
!
!
!
!
!
!
!
interface Ethernet0
 ip address 10.0.0.2 255.255.255.0
 ip nat inside
 ip virtual-reassembly
 load-interval 30
!        
interface Ethernet1
 no ip address
 load-interval 30
 duplex auto
 pppoe enable
 pppoe-client dial-pool-number 1
!        
interface Ethernet2
 no ip address
 shutdown
!        
interface FastEthernet1
 duplex auto
 speed auto
!        
interface FastEthernet2
 duplex auto
 speed auto
!        
interface FastEthernet3
 duplex auto
 speed auto
!        
interface FastEthernet4
 duplex auto
 speed auto
!        
interface Dialer0
 ip address negotiated
 ip nat outside
 ip virtual-reassembly
 encapsulation ppp
 dialer pool 1
 ppp pap sent-username ****** password ***************
!        
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer0
!        
no ip http server
no ip http secure-server
!        
ip nat inside source list 18 interface Dialer0 overload
!        
access-list 18 permit 10.0.0.0 0.0.0.255
!        
!        
control-plane
!        
banner motd ^C
DO NOT LOGIN ^C
alias exec s sh ip int br
alias exec r sh run
alias exec t configure terminal
alias exec a sh arp
alias exec c sh clock
!        
line con 0
 no modem enable
line aux 0
line vty 0 4
 password 7 *******
 login   
!        
scheduler max-task-time 5000
end