IT Certification

Did you all here this before about this company koenig-solutions

This company are base in India. It provide a lot of training/certification. The best this is.. if you dont have the place to stay when doing the training.. they can provided it.. It include in the training/cert price… Most of the training is boot camp ,RHCE, NCLE, Solaris, CCNA, CCNP, MCSE, LP1,LP12, to many…

Here i provided same example of the training including the price and accomondation.

Source: koenig-solutions

CLP/CLE

Contact:

Delhi Centre
Koenig Solutions Pvt. Ltd.
20-A, IInd Floor, Shivaji Marg, Moti Nagar
New Delhi, Postal Code – 110015, (India)

Shimla (Himalaya Mountains) Centre
Koenig Solutions Pvt. Ltd.
Sunbreeze Inn building
Main Bus Stand
Sanjauli, Shimla-171006.
Himachal Pradesh (India)

Goa Centre
Koenig Solutions Pvt. Ltd.
3rd Floor, B/T1,
Campal Trade Centre,
Opp. Kala Akademy,
Panjim, Goa – 403001, (India)

Dehradun Centre
Koenig Solutions Pvt Ltd,
Plot # 22, IT Park,
Sahashdhara Road,
Dehradun, (India)

Fax: +91 11 25886909
Email: info@koenig-solutions.com

Telephone 24 x 7 : +91 98102 64199
(only from outside India)

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Internet Slow.. Cable problem

I just read from bloomberg got the problem for the world communication especially the internet connection.

Credit to:Bloomberg

Severed Cables in Mediterranean Disrupt Communication (Update4)

Dec. 19 (Bloomberg) — Internet and telephone communications between the Middle East and Europe were disrupted after three undersea cables connecting Italy and Egypt in the Mediterranean Sea were damaged.

The failures cut the flow of “data of various kinds” between Europe and the Middle East, and there’s no timeframe for when communications will be restored, said Sanjeev Gaur, director of assurance at Reliance Globalcom Ltd. in India. France Telecom SA, which plans to send a maintenance boat to fix the problem, said the situation should be back to normal by Dec. 31.

Three cable systems carrying more than 75 percent of traffic between the Middle East, Europe and America were damaged, according to the U.K.’s Interoute Plc, which operates a fiber- optic data network connecting 92 cities. The cables run from Alexandria in northern Egypt to Sicily in southern Italy. In January, an anchor severed the cables outside Alexandria after bad weather conditions forced ships to moor off the coast.

“The information we have is a bit sketchy, but chances are that it will have been an anchor again,” Jonathan Wright, Interoute’s director of wholesale products, said in a telephone interview. “Close to 90 percent of all the data traffic between Europe and the Middle East is carried on these three cable systems.”

Interoute said the January incident brought down 70 percent of the Internet network in India and the Middle East.

Egyptian Outage

Customer services and some mobile-phone customers at Vodafone Group Plc’s Egyptian unit are affected by the cable failure, said Simon Gordon, a spokesman for the U.K. company. Egypt is the only country where the company is aware of any problems linked to the failure, he said. Most mobile-phone calls are routed through fixed-line cables at some point.

Verizon Communications Inc., the second-largest U.S. phone company, said it has rerouted traffic for its Verizon Business customers making calls to the Middle East by siphoning it to Europe and the U.S. and then down through Asia, spokeswoman Linda Laughlin said in an interview.

The rerouting slowed some traffic to about half its normal speed, Laughlin said. Point-to-point customers still don’t have connections, and Verizon doesn’t have information on how many subscribers are affected. The company expects repairs to be completed by early next week, she said.

Portugal Telecom SGPS SA, Portugal’s biggest phone company, has redirected traffic through other cables in the region and therefore the “impact is very small,” said a company official. Sonaecom SGPS SA, Portugal’s second-biggest fixed-line phone company, also said that it’s diverting traffic to other routes.

‘Greatly Disturbed’

France Telecom’s Orange mobile-phone unit said the cable failure “greatly disturbed” the traffic between Europe and parts of Asia. At one point as much as 55 percent of voice traffic in Saudi Arabia, 52 percent in Egypt and 82 percent in India was out of service, according to Orange.

Internet traffic “from Mumbai to London has now been rerouted via Hong Kong which may lead to congestion and increased latency on this route,” Reliance said in an e-mailed “traffic disruption update,” adding that it is working with the affected customers to restore all services. The company said it will publish another update on its Web site tomorrow.

“You can reroute the data through other cables, but that increases traffic and can potentially create bottlenecks,” Interoute’s Wright said. “So Internet connections may slow down and some phone calls could get disrupted.”

Weather, Sea Conditions

Some of Interoute’s clients in the U.K. and Southern France are probably affected by the failure, Wright said.

“It’s difficult to forecast how long it will take to fix the problem as it depends on the weather and sea conditions in the Mediterranean,” Wright said.

A fault is affecting the SMW4 cable near the Alexandria cable station, the FLAG FEA cable is down and the SMW3 cable system is also affected, according to information received from Telstra. Flag Telecom Group Ltd., a Reliance Globalcom unit, operates FLAG FEA and the other cables are owned by groups of phone companies across the regions.

Reliance Globalcom doesn’t know exactly what happened and engineers are working on the problem, said Anurag Joshi, head of the company’s global network operations center.

The SMW4 cable, also known as SEA-ME-WE 4or South East Asia-Middle East-Western Europe 4 cable network, connects 12 countries: Pakistan, Indonesia, Singapore, Malaysia, Bangladesh, India, Sri Lanka, United Arab Emirates, Saudi Arabia, Egypt, Italy and France.

France Telecom said one of its maintenance boats in the Mediterranean area is headed to the region for a relief mission with 20 kilometers of spare cable on board.

Priority will be to recover the SEA-ME-WE 4 cable, then the SEA-ME-WE 3 cable, France Telecom said, adding that Sea Me We4 could be operating by Dec. 25 and the situation should be back to normal by Dec. 31.

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My Wish List

Completed my self studies on:

Novell Course

  • 3071-SUSE Linux Enterprise Server10 Fundamentals
  • 3072-SUSE Linux Enterprise Server10 Advance Administration
  • 3073-SUSE Linux Enterprise Server10 Advance Admin

Then attend to Novell Certified Linux Professional 10 Fast Track.

Then any Professional Certification

  • : NCLP > NCLE
  • : RHCT > RHCE
  • : CCNA??
  • Good career in Server/Network Field – Vendor/Support or Large Company
  • Continue my studies in Degree – Part Time Classes.
  • Get my own Car and House

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Network Topologies

Network Topologies

Introduction

Network topologies can take a bit of time to understand when you’re all new to this kind of cool stuff, but it’s very important to fully understand them as they are key elements to understanding and troubleshooting networks and will help you decide what actions to take when you’re faced with network problems.

I will try to be as simple as possible and give some examples you can relate to, so let’s get stuck right into this stuff !

The Stuff 🙂

There are two types of topologies: Physical and Logical. The physical topology of a network refers to the layout of cables, computers and other peripherals. Try to imagine yourself in a room with a small network, you can see network cables coming out of every computer that is part of the network, then those cables plug into a hub or switch. What you’re looking at is the physical topology of that network !

Logical topology is the method used to pass the information between the computers. In other words, looking at that same room, if you were to try to see how the network works with all the computers talking (think of the computers generating traffic and packets of data going everywhere on the network) you would be looking at the logical part of the network. The way the computers will be talking to each other and the direction of the traffic is controlled by the various protocols (like Ethernet) or, if you like, rules.

If we used token ring, then the physical topology would have to change to meet the requirements of the way the token ring protocol works (logically).

If it’s all still confusing, consider this: The physical topology describes the layout of the network, just like a map shows the layout of various roads, and the logical topology describes how the data is sent accross the network or how the cars are able to travel (the direction and speed) at every road on the map.

The most common types of physical topologies, which we are going to analyse, are: Bus, Hub/Star and Ring

The Physical Bus Topology

Bus topology is fairly old news and you probably won’t be seeing much of these around in any modern office or home.

With the Bus topology, all workstations are connect directly to the main backbone that carries the data. Traffic generated by any computer will travel across the backbone and be received by all workstations. This works well in a small network of 2-5 computers, but as the number of computers increases so will the network traffic and this can greatly decrease the performance and available bandwidth of your network.

As you can see in the above example, all computers are attached to a continuous cable which connects them in a straight line. The arrows clearly indicate that the packet generated by Node 1 is transmitted to all computers on the network, regardless the destination of this packet.

Also, because of the way the electrical signals are transmitted over this cable, its ends must be terminated by special terminators that work as “shock absorbers”, absorbing the signal so it won’t reflect back to where it came from. The value of 50Ohms has been selected after carefully taking in consideration all the electrical characteristics of the cable used, the voltage that the signal which runs through the cables, the maximum and minimum length of the bus and a few more.

If the bus (the long yellow cable) is damaged anywhere in its path, then it will most certainly cause the network to stop working or, at the very least, cause big communication problems between the workstations.

Thinnet – 10 Base2, also known as coax cable (Black in colour) and Thicknet – 10 Base 5 (Yellow in colour) is used in these type of topologies.

The Physical HUB or STAR Topology

The Star or Hub topology is one of the most common network topologies found in most offices and home networks. It has become very popular in contrast to the bus type (which we just spoke about), because of the cost and the ease of troubleshooting.

The advantage of the star topology is that if one computer on the star topology fails, then only the failed computer is unable to send or receive data. The remainder of the network functions normally.

The disadvantage of using this topology is that because each computer is connected to a central hub or switch, if this device fails, the entire network fails!

A classic example of this type of topology is the UTP (10 base T), which normaly has a blue colour. Personally I find it boring, so I decided to go out and get myself green, red and yellow colours 🙂

The Physical Ring Topology

In the ring topology, computers are connected on a single circle of cable. Unlike the bus topology, there are no terminated ends. The signals travel around the loop in one direction and pass through each computer,
which acts as a repeater to boost the signal and send it to the next computer. On a larger scale, multiple LANs can be connected to each other in a ring topology by using Thicknet coaxial or fiber-optic cable.

The method by which the data is transmitted around the ring is called token passing. IBM’s token ring uses this method. A token is a special series of bits that contains control information. Possession of the token allows a network device to transmit data to the network. Each network has only one token.

The Physical Mesh Topology

In a mesh topology, each computer is connected to every other computer by a separate cable. This configuration provides redundant paths through the new work, so if one computer blows up, you don’t lose the network 🙂 On a large scale, you can connect multiple LANs using mesh topology with leased telephone lines, Thicknet coaxial cable or fiber optic cable.

Again, the big advantage of this topology is its backup capabilities by providing multiple paths through the network.

The Physical Hybrid Topology

With the hybrid topology, two or more topologies are combined to form a complete network. For example, a hybrid topology could be the combination of a star and bus topology. These are also the most common in use.

Star-Bus

In a star-bus topology, several star topology networks are linked to a bus connection. In this topology, if a computer fails, it will not affect the rest of the network. However, if the central component, or hub, that attaches all computers in a star, fails, then you have big problems since no computer will be able to communicate.

Star-Ring

In the Star-Ring topology, the computers are connected to a central component as in a star network. These components, however, are wired to form a ring network.

Like the star-bus topology, if a single computer fails, it will not affect the rest of the network. By using token passing, each computer in a star-ring topology has an equal chance of communicating. This allows for greater network traffic between segments than in a star-bus topology.

Source & Credit to : http://www.firewall.cx/

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Introduction To Networking

Introduction To Networking

Introduction

A network is simply a group of two or more Personal Computers linked together. Many types of networks exist, but the most common types of networks are Local-Area Networks (LANs), and Wide-Area Networks (WANs).

In a LAN, computers are connected together within a “local” area (for example, an office or home). In a WAN, computers are further apart and are connected via telephone/communication lines, radio waves or other means of connection.

How are Networks Categorized?

Networks are usually classified using three properties: Topology, Protocol and Architecture.

Topology specifies the geometric arrangement of the network. Common topologies are a bus, ring and star.You can check out a figure showing the three common types of network topologies here.

Protocol specifies a common set of rules and signals the computers on the network use to communicate. Most networks use Ethernet, but some networks may use IBM’s Token Ring protocol. We recommend Ethernet for both home and office networking. For more information, please select the Ethernet link on the left.

Architecture refers to one of the two major types of network architecture: Peer-to-peer or client/server. In a Peer-to-Peer networking configuration, there is no server, and computers simply connect with each other in a workgroup to share files, printers and Internet access.

This is most commonly found in home configurations and is only practical for workgroups of a dozen or less computers. In a client/server network there is usually an NT Domain Controller, to which all of the computers log on. This server can provide various services, including centrally routed Internet Access, mail (including e-mail), file sharing and printer access, as well as ensuring security across the network. This is most commonly found in corporate configurations, where network security is essential.

Source & Credit to : http://www.firewall.cx/

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