It Expains How To Design Various Types Of Networks (Term Paper Sample)

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Introduction.
A network should be designed such that it is adjustable and scalable to the demands for the new services. The designed network should be able to adjust to rising traffic loads in order to maintain response time of the applications. In order to support a network-based economy, the created network should be available almost 100 percent of the time.
The network should be able to detect and automatically malicious parties. The security measures of the network should be considered during design. This will avoid unexpected security issues. The principles of hierarchical network design and systematic design methodology should be followed to design a network that not only manageable but also supportable CITATION Ton02 \l 1033 (Kenyon, 2002).
Network Design Overview
Currently information networks are essential to both large and small. They allow connection of people, support applications and provision of access to resources that are necessary for the success of the business. However due to the daily requirements of businesses, the design of the networks are gradually becoming complex. It is not recommendable to connect standalone components of a network without a detailed planning and design.
Network Requirements
Today, the economy needs a network that is available most of the time in order to offer quality service. A reliable network should be available almost 100 percent of the business operation time. The designed network should be able to protect automatically against security incidents that may arise. These business networks should be able to adapt to changing traffic loads in order to retain consistent application response times CITATION Dar93 \l 1033 (Spohn, 1993). It is not practical to implement a network by connecting several standalone components without proper planning and design.
Network Requirements
The business needs some requirements for the network. The requirements include:
(i) The network should be available all the time, even in the event of equipment failure, failed links and overloaded conditions.
(ii) The network should reliable in delivering applications and offer reasonable response times between the hosts and the clients.
(iii) The security of the network should be high. The data being transmitted over the network and the data stored in the devices connected to it should be protected.
(iv) The network should designed to allow for modification to adapt to growth of the network and business changes.
(v) Since failures may occur, the troubleshooting of the network needs to be easy. The process of locating and fixing problems should consume little time.
Fundamental Design Goals
The requirements reduce to four fundamental design goals. These goals are:
(i) Scalability
The network to be designed should be scalable. This means that the network can grow to include new users and remote sites in the future. A scalable network, also, accommodates new application without significant effect on the quality of service offeredCITATION Pri99 \l 1033 (Oppenheimer & Priscilla, 1999).
(ii) Availability
A network is said to be available when it offers consistent and reliable performance around the clock. Also, when a single link fails, the performance of the network will significantly affected.
(iii) Security.
The security of a network is taken into consideration during the design of the network. Adding this feature after network design may not be effective. During the design of a network, the locations of security devices, firewall and filters is critical to the protection of network resources.
(iv) Manageability.
The designed network should allow the staff to manage it regardless of the care is taken during the design. A network that is complex and difficult to maintain will not function efficiently and effectively.
Hierarchical Network Design
A hierarchical design, in networking, is used to group devices into several networks. The networks need to be organized in a layered approach. The design of a hierarchical network model is made up of three basic layers:
(i) The core layer: this is a layer that connects distribution layer devices
(ii) The distribution layer: this layer interconnects the smaller local networks
(iii) The access layer: this is a layer which connects network hosts and the end devices.
The hierarchical network has several advantages over the flat network design. The value of segmenting a flat network into manageable hierarchical blocks is that the local traffic remains local. The traffic destined for different networks is the only traffic moved to a higher layer. The following is the design of a hierarchical network.
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262305367945595007118410463813611838Distribution layer.
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Layer.
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Modular Design of Cisco Enterprise Architectures.
The figure below shows how Cisco Enterprise Architectures can be used to divide the three-layer hierarchical network design into modular areas. Each module represents an area with different logical or physical connectivity. It shows where various functions take place in the network. This modularity allows for flexibility in the network design. This facilitates the implementation and troubleshooting of the network. The three areas to be focused on in modular network design are:
(i) The Enterprise campus.
This is an area that contains the network components needed for independent operation of a single location. The campus core, building distribution and building access are located.
(ii) The Server farm.
This is a component of an enterprise campus that protects the server resources and offers a reliable high-speed connectivity.
(iii) Enterprise edge:
This is an area that filters traffic that comes into the campus network from external networks and routes it to the enterprise network. This area has all the components that are needed for the efficient and secure exchange of data between the enterprise campus and various remote locations.
Enterprise campus Enterprise edge. WAN and internet.
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26741910100Building access00Building access
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208759269370016303926937007416681098550034505711045400
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The Cisco Enterprise Architectures modular framework shown above has the following advantages:
(i) It results in a deterministic network that has well-defined boundaries between the modules. This gives clear demarcation points such that the origin of the traffic can be singled out.
(ii) The task of ensuring that each module is independent is eased. Therefore, the needs of each area can be focused on separately.
(iii) It offers scalability by enabling enterprises to easily add modules. As network become increasingly complex, a new functional modules may be added.
(iv) It allows for addition of new services and solutions without many changes on the underlying network design.
Matching the characteristics of the Cisco Enterprise Architecture and the hierarchal model results in the following model: Floor 1.
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361938284216-146649285115552953270773461453387331391598596256Floor 2.Firewall.
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-181011301421
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3485072204386Frame relay.00Frame relay.Servers.
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Other buildings.
Redundant Links
Implementation of redundant links at the core layer will make sure that the network devices will find alternative paths to send data in case of a failure. The Layer 3 devices are positioned at th...