The Internet and Standarts

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The Internet is a worldwide, publicly accessible network of networks. It enables individuals and businesses alike, through interconnected computer networks, to share information, resources, and services.
In the beginning, the Internet was used strictly for scientific, educational, and military research. In 1991, regulations changed to allow businesses and consumers to connect as well. The Internet has grown rapidly, and is now global. New technologies are continuously being developed that make the Internet easier and more attractive to use. Online applications are available to the Internet user, including email, web browsing, streaming music and video, gaming, and instant messaging.

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The Internet and Standarts

The Internet is a worldwide, publicly accessible network of networks. It enables individuals and businesses alike, through interconnected computer networks, to share information, resources, and services.

In the beginning, the Internet was used strictly for scientific, educational, and military research. In 1991, regulations changed to allow businesses and consumers to connect as well. The Internet has grown rapidly, and is now global. New technologies are continuously being developed that make the Internet easier and more attractive to use. Online applications are available to the Internet user, including email, web browsing, streaming music and video, gaming, and instant messaging.

The way people interact, share information, and even do business is changing to keep up with the continuous evolution of this global network. The Internet is creating a wider audience and consumer base for whatever message, product, or service can be delivered. For many businesses, having Internet access has become critical, not only for communication but also for day-to-day operation. Some of the business uses of the Internet include:

    • E-commerce
    • Communications
    • Collaboration and training

With the increasing number of new devices and technologies coming online, how is it possible to manage all the changes and still reliably deliver services such as email? The answer is Internet standards.

A standard is a set of rules that determines how something must be done. Networking and Internet standards ensure that all devices connecting to the network use the same set of rules. Using standards, it is possible for different types of devices to send information to each other over the Internet. For example, the way in which an email is formatted, forwarded, and received by all devices is done according to a standard. If one person sends an email via a personal computer, another person can use a mobile phone to receive and read the email as long as the mobile phone uses the same standards as the personal computer.


An Internet standard is the end result of a comprehensive cycle of discussion, problem solving, and testing. When a new standard is proposed, each stage of the development and approval process is recorded in a numbered Request for Comments (RFC) document so that the evolution of the standard is tracked.

There are thousands of Internet standards that help define the rules for how devices communicate on networks. These different standards are developed, published, and maintained by a variety of different organizations. Because these organizations create and maintain standards, millions of individuals are able to connect to the Internet using a variety of devices, including personal computers, mobile phones, handheld personal digital assistants (PDAs), MP3 players, and even televisions.

ISP Requirements

An ISP requires a variety of devices to accept input from end users and provide services. To participate in a transport network, the ISP must be able to connect to other ISPs. An ISP must also be able to handle large volumes of traffic.

Some of the devices required to provide services include:

    • Access devices that enable end users to connect to the ISP, such as a DSL Access Multiplexer (DSLAM) for DSL connections, a Cable Modem Termination System (CMTS) for cable connections, modems for dialup connections, or wireless bridging equipment for wireless access.
    • Border gateway routers to enable the ISP to connect and transfer data to other ISPs, IXPs, or large business enterprise customers.
    • Servers for such things as email, network address assignment, web space, FTP hosting, and multimedia hosting.
    • Power conditioning equipment with substantial battery backup to maintain continuity if the main power grid fails.
    • High capacity air conditioning units to maintain controlled temperatures.

ISPs, like other businesses, want to expand so that they can increase their income. The ability to expand their business depends on gaining new subscribers and selling more services. However, as the number of subscribers grows, the traffic on the network of the ISP also grows.

Eventually, the increased traffic may overload the network, causing router errors, lost packets, and excessive delays. In an overloaded network, subscribers can wait for minutes for a web page to load, or may even lose network connection. These customers may choose to switch to a competing ISP to get better performance.

Loss of customers directly translates to loss of income for an ISP. For this reason, it is important that the ISP provides a reliable and scalable network.


Scalability is the capacity of a network to allow for future change and growth. Scalable networks can expand quickly to support new users and applications without affecting the performance of the service being delivered to existing users.

The most scalable devices are those that are modular and provide expansion slots for adding modules. Different modules can have different numbers of ports. In the case of a chassis router, some modules also offer different interface options, allowing for different connection options on the same chassis.


Roles and Responsibilities an ISP

ISP organizations consist of many teams and departments which are responsible for ensuring that the network operates smoothly and that the services are available.

Network support services are involved in all aspects of network management, including planning and provisioning of new equipment and circuits, adding new subscribers, network repair and maintenance, and customer service for network connectivity issues.

When a new business subscriber orders ISP services, the various network support service teams work together to ensure that the order is processed correctly and that the network is ready to deliver those services as quickly as possible.

Each of the network support service teams have their own roles and responsibilities:

    • Customer Service receives the order from the customer and ensures that the specified requirements of the customer are accurately entered into the order tracking database.
    • Planning and Provisioning determines whether the new customer has existing network hardware and circuits and if new circuits need to be installed.
    • The On-site Installation is advised of which circuits and equipment to use and then installs them at the customer site.
    • The Network Operations Center (NOC) monitors and tests the new connection and ensures that it is performing properly.
    • The Help Desk is notified by the NOC when the circuit is ready for operation and then contacts the customer to guide them through the process of setting up passwords and other necessary account information.

ISP Help Desk Organization

Many business operations depend on the connection to the local network and to the Internet. Because of this, solving network problems is a top priority for businesses.

ISPs provide the Internet connection for businesses, and they provide their customers support for problems that occur with Internet connectivity. This support usually includes assistance with customer equipment problems. ISP support is typically provided through the ISP help desk. Whether the problem is connecting to the Internet or getting email, the ISP help desk is usually the first place a user or business turns to for help.

ISP help desk technicians have the knowledge and experience to fix problems and get users connected. ISP help desk technicians provide solutions to customer problems with the goal of network optimization and customer retention.

A good help desk team ensures that problems are resolved quickly and to the satisfaction of the customer. Providing Internet services is a highly competitive business, and poor service can cause the ISP to lose customers to competing ISPs.

At an ISP, there are usually three levels of customer support:

  • Level 1 is for immediate support handled by junior-level help desk technicians.
  • Level 2 handles calls that are escalated to more experienced telephone support.
  • Level 3 is for calls that cannot be resolved by phone support and require a visit by an on-site technician.

In addition to ISPs, many other types of medium to large businesses employ help desk or customer support teams. The titles assigned to the technicians may vary from those described here, although the three-level hierarchy is the most common structure. Depending on the size of the organization, the help desk can consist of one person that performs all three levels of support, or it can be a comprehensive call center with elaborate call routing facilities and escalation rules. Some ISPs and businesses contract out their help desk functions to a third-party call center company, which provides the services of Level 1 and Level 2 technicians.


Roles of ISP Technicians

When a user initially contacts the help desk to resolve an issue, the call or message is usually directed to a Level 1 support technician. Level 1 support is usually an entry-level position that provides junior technicians with valuable experience. Many customer issues are resolved by the Level 1 support technician.

Issues that cannot be resolved are sent to Level 2 support, which typically has fewer agents available. The duties and responsibilities of the Level 2 technician are similar to that of the Level 1 technician, but they are at a higher skill level. These agents are expected to solve problems that are more challenging and require more knowledge.

Many larger service providers have expanded their businesses to include managed services or on-site support of a customer network. Organizations that provide managed services are sometimes referred to as Managed Service Providers (MSP). Managed services can be provided by ISPs, telecommunications service providers, or other types of computer and network support organizations. When an ISP is providing managed services, it often requires technicians to visit customer sites for the purpose of installation and support. This type of service represents Level 3 support.

Level 3 support is usually in accordance with a Service Level Agreement (SLA). An SLA resembles an insurance policy, because it provides coverage or service if there is a computer or network problem.


Interacting with Customers

Help desk technicians may be required to provide phone support, email support, web-based support, online chat support, and possibly on-site support. They are often the first point of contact for frustrated and anxious customers. Until a problem is solved, help desk technicians may continue to get calls and correspondence asking for status updates and time estimates to resolve an issue.

The help desk technician must be able to stay focused in an environment with frequent interruptions and perform multiple tasks efficiently and accurately. It can be difficult to consistently maintain a positive attitude and provide a high level of service. The help desk technician has to have excellent interpersonal skills and effective communication skills, both oral and written. The technician must be able to work independently and as part of a team.

It is important for the help desk technician to be able to handle customer issues with speed, efficiency, and professionalism. Help desk technicians should conduct themselves in accordance with the company's customer service philosophy. A customer service philosophy is an organization-wide ethic shared by everyone from top management to operational staff.

Basic incident management procedures must be followed every time a help desk technician receives a call and begins troubleshooting issues. Incident management includes opening a trouble ticket and following a problem-solving strategy. Problem-solving techniques include using troubleshooting flowcharts, addressing questions in a template format, and maintaining proper ticket escalation procedures.

A help desk script is used by the help desk technician to gather information and cover the important facts about customer incident.

In addition to technical ability, help desk technicians must be able to greet customers pleasantly and be professional and courteous throughout the call.

Customer service and interpersonal skills are especially important when handling difficult clients and incidents. The help desk technician must know how to relieve customer stress and respond to abusive customers.

Opening trouble tickets and logging information on the tickets are critical to help desk operation. When there are many calls relating to a single problem or symptom, it is helpful to have information on how the problem was resolved in the past. It is also important to relay to the customer what is being done to solve the problem. Good information on open trouble tickets helps communicate accurate status, both to the customer and other ISP personnel.

While many issues can be handled remotely, some problems require an on-site visit to the customer premises to install and troubleshoot equipment. When a technician goes on-site, it is important to represent their organization in a professional manner. A professional knows how to make the customer feel at ease and confident in the technician's skills.

On the first visit to a customer location, it is important for the technician to make a good impression. Personal grooming and the way the technician is dressed are the first things the customer notices. If the technician makes a bad first impression, it may be difficult to change that impression and gain the confidence of the customer. Many employers provide a uniform or have a dress code for their on-site technicians.

The language and attitude of the technician also reflect on the organization that the technician represents. A customer may be anxious or concerned about how the new equipment will operate. When speaking with a customer, the technician should be polite and respectful, and answer all customer questions. If the technician does not know an answer to a customer question or if additional information is required, the technician should write down the customer inquiry and follow up on it as soon as possible.


Using the OSI Model

When a network connectivity problem is reported to the help desk, many methods are available to diagnose the problem. One common method is to troubleshoot the problem using a layered approach. A layered approach requires that the network technician be familiar with the various functions that occur as messages are created, delivered, and interpreted by the network devices and hosts on the network.

Moving data across a network is best visualized using the seven layers of the Open Systems Interconnection model, commonly referred to as the OSI model. The OSI model breaks network communications down into multiple processes. Each process is a small part of the larger task.

For example, in a vehicle manufacturing plant, the entire vehicle is not assembled by one person. Rather the vehicle moves from station to station where specialized teams add specific components. The complex task of assembling a vehicle is made easier by breaking it into manageable and logical tasks. This process also makes troubleshooting easier. When a problem occurs in the manufacturing process, it is possible to isolate the problem to the specific task where the defect was introduced, and then fix it.

In a similar manner, the OSI model can be used as a means to focus on a layer when troubleshooting to identify and resolve network problems.

The seven layers of the OSI model are divided into two parts: upper layers and lower layers.

The term upper layer is sometimes used to refer to any layer above the transport layer of the OSI model. The upper layers deal with application functionality and are generally implemented only in software. The highest layer, the application layer, is closest to the end user.

The term lower layer is sometimes used to refer to any layer below the session layer. The combined functionality of the lower layers handles data transport. The physical layer and the data link layer are implemented in both hardware and software. The physical layer is closest to the physical network medium, or network cabling. The physical layer actually places information on the medium.

End stations, like clients and servers, usually work with all seven layers. Networking devices are only concerned with the lower layers. Hubs work on Layer 1, switches on Layers 1 and 2, routers on Layers 1, 2 and 3, and firewalls on Layers 1, 2, 3, and 4.


OSI Model Protocols and Technologies

When using the OSI model as a framework for troubleshooting, it is important to understand which functions are performed at each layer, and what network information is available to the devices or software programs performing these functions. For example, many processes must occur for email to successfully travel from the client to the server. The OSI model divides the task of sending and receiving email into smaller, distinct steps that correspond with the seven layers.

Step 1: Upper layers create the data.

When a user sends an email message, the alphanumeric characters within the message are converted to data that can travel across the network. Layers 7, 6, and 5 are responsible for ensuring that the message is placed in a format that can be understood by the application running on the destination host. This process is called encoding. The upper layers then send the encoded messages to the lower layers for transport across the network. Transporting the email to the correct server relies on the configuration information provided by the user. Problems that occur at the application layer are often related to errors in the configuration of the user software programs.

Step 2: Layer 4 packages the data for end-to-end transport.

The data that comprises the email message is packaged for network transport at Layer 4. Layer 4 breaks the message down into smaller segments. A header is placed on each segment indicating the TCP or UDP port number that corresponds to the correct application layer application. Functions in the transport layer indicate the type of delivery service. Email utilizes TCP segments, therefore packet delivery is acknowledged by the destination. Layer 4 functions are implemented in software that runs on the source and destination hosts. However, because firewalls often use the TCP and UDP port numbers to filter traffic, problems that occur at Layer 4 can be caused by improperly configured firewall filter lists.

Step 3: Layer 3 adds the network IP address information.

The email data received from the transport layer is put into a packet that contains a header with the source and destination network IP addresses. Routers use the destination address to direct the packets across the network along the appropriate path. Incorrectly configured IP address information on the source or destination system can cause Layer 3 problems to occur. Because routers also use IP address information, router configuration errors can cause problems at this layer.

Step 4: Layer 2 adds the data link layer header and trailer.

Each network device in the path from the source to the destination, including the sending host, encapsulates the packet into a frame. The frame contains the physical address of the next directly-connected network device on the link. Each device in the chosen network path requires framing so that it can connect to the next device. Switches and network interface cards (NICs) use the information in the frame to deliver the message to the correct destination device. Incorrect NIC drivers, interface cards, and hardware problems with switches can cause Layer 2 problems to occur.

Step 5: Layer 1 converts the data to bits for transmission.

The frame is converted into a pattern of 1s and 0s (bits) for transmission on the medium. A clocking function enables the devices to distinguish these bits as they travel across the medium. The medium can change along the path between the source and destination. For example, the email message can originate on an Ethernet LAN, cross a fiber campus backbone, and cross a serial WAN link until it reaches its destination on another remote Ethernet LAN. Layer 1 problems can be caused by loose or incorrect cables, malfunctioning interface cards, or electrical interference.

At the receiving host, the processes described in steps 1 through 5 are reversed, with the message traveling back up the layers to the appropriate application.


Troubleshooting the OSI Model

As a theoretical model, the OSI model defines the protocols, hardware, and other specifications that operate at the seven layers.

The OSI model also provides a systematic basis for troubleshooting a network. In any troubleshooting scenario, the basic problem-solving procedure includes the following steps:

1. Define the problem.

2. Isolate the cause of the problem.

3. Solve the problem.

  • Identify and prioritize alternative solutions.
  • Select one alternative as the solution.
  • Implement the solution.
  • Evaluate the solution.

If an identified solution does not fix the problem, undo any changes and proceed to the next possible solution. Go through the steps until a solution works.

In addition to the basic problem-solving procedures, the OSI model can be used as a guideline for troubleshooting. Using a layered model, there are three different troubleshooting approaches that a technician can use to isolate the problem:

  • Bottom-Up - The bottom-up approach starts with the physical components of the network and works its way up the layers of the OSI model. Bottom-up troubleshooting is an effective and efficient approach for suspected physical problems.
  • Top-Down - The top-down approach starts with the user application and works its way down the layers of the OSI model. This approach starts with the assumption that the problem is with the application and not the network infrastructure.
  • Divide-and-Conquer - The divide-and-conquer approach is generally used by more experienced network technicians. The technician makes an educated guess targeting the problem layer and then based on the observed results, moves up or down the OSI layers.

Using the OSI model as a guide, the help desk technician can query the customer to help define the problem and isolate the cause.

The help desk technician usually has a standard checklist or script to follow when troubleshooting a problem. Often the script takes a bottom-up approach to troubleshooting. This is because physical problems are usually the simplest to diagnose and repair, and the bottom-up approach starts with the Physical Layer.

Layer 1 Troubleshooting

The technician starts with Layer 1 issues first. Remember, Layer 1 deals with the physical connectivity of the network devices. Layer 1 problems often involve cabling and electricity, and are the reasons for many help desk calls. Some of the more common Layer 1 problems include:

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