Unit 1 Assignment And Labs

the system will, on a large scale, form a network of independent components which ultimately

transmission of structures to generate digital indicators distorted by the loss of the transmission. Hubs function as repeaters by transmitting messages to the related computers. The repeater does intellectual routing that can be acted upon by routers and bridges (Vachhani,

HUB - An Ethernet hub, active hub, network hub, repeater hub, multiport repeater or hub is a device for connecting multiple Ethernet devices together and making them act as a single network segment.

A Star topology is the second type of topology represented. This topology is easy to install as well as being easy to expand by connecting additional nodes or devices. Faults are easily detected and parts are easy to remove. In a Start topology, when devices need to be added or removed, it does not cause disruptions to the network. This type of topology is used for many different applications, ranging from small to large networks. (FCIT, Univ. of Florida)

Fiber optic cables will be installed and configured on the physical star network topology spread throughout the 600 user network infrastructure. The main equipment that will be used during the implementation of the physical star topology will be the patch panel with an array of RJ-45 female connectors with terminals to connect wires to all the 600 users across the network infrastructure.

Star – All computers and devices are connected to a centrally situated hub or switch. The hub or switch collects and distributes the flow of knowledge at intervals the network. It’s higher to use a switch than a hub as a result of a switch transmits the info to the supposed recipient instead of to all or any hosts on a network.

The timing of the systems must be predictable and this is done by defining task switching

The link in the protocol is assumed to be bi-directional. In GEAR, each node has two types of cost parameter:

Provides multi layered security: Security starts from physical layer from protecting against ARP Cache, intruders, vandals and thieves. Physical security is provided based on the needs, maintenance

The main topologies are Bus (All Workstations are connected to one line), Star (All Workstations are connected to a central hub), Ring (All workstations are connected to fellow workstations left and right of them) and Mesh (All workstations are connected to each other). A lot of topologies are designed to allow more workstations to be added at a later date. But a lot of topologies also have weaknesses, such as the Bus topology and the Ring topology, which would both break down if a node was to fail.

Enable maintenance to be performed in any of Huffman 's hubs regardless of the vehicles home hub location very good.

A high level of interconnectedness between system components, reliance on indirect information sources, an unpredictable environment, or incomprehensibility of a system to its operators indicates complexity within a system (Perrow, 1999). Since systems are designed, run and built by humans, they cannot be perfect. Every part of the system is subject to failure; the design can be faulty, as can the equipment, the procedures, the operators, the supplies, and the environment. Since nothing is perfect, humans build in safeguards, such as redundancies, buffers, and alarms that tell operators to take corrective action. But occasionally two or more failures can interact in ways that could not be anticipated. These unexpected interactions of failures can defeat the safeguards, and if the system is also “tightly coupled” thus allowing failures to cascade, it can bring down a part or all of system. The vulnerability to unexpected interactions that defeat safety systems is an inherent part of highly complex systems; they cannot avoid this (Perrow, 1984).

In a star network, all cables or nodes are connected to one central core which is the hub. This tends to be the most reliable topology.

this hub system although useful for Apple and Fritz, was a bit riskier for suppliers as cases

Un système dispose d 'une grande dimension est tout système qui se compose de nombreux sous-systèmes et a de nombreuses entrées et sorties. Ce modèle a une forte dynamique de contrôle. La répartition géographique de ce système exige beaucoup de problèmes qui sont étroitement liés à sa dimension. Ceci nécessite, pour la commande tolérante aux défauts du système, la fiabilité des voies de communication c 'est à dire la validité des informations qui y transitent en présence des défauts parce que des incertitudes se produisent aussi. Le comportement et les propriétés de l 'ensemble du système ne peuvent pas être complètement décrits par un modèle mathématique. L 'identification de l 'ensemble du système est impossible parce que certains troubles ou signaux de commande ne sont pas connus. D 'autres incertitudes résultent de l 'agrégation ou la simplification de modèle qui a été délibérément effectué. La disponibilité de l 'information sur le comportement de l 'ensemble du système et des sous-systèmes est restreinte. L 'ampleur des informations du système à grande dimension évoque le problème de mémorisation de données et par conséquent le problème de la capacité du calculateur, bien qu 'on commence à donner moins d 'importance à ce problème avec l 'avènement des nouvelles technologies de calculateurs ayant de grandes capacités. Le temps d 'exécution est défini par le nombre d 'opérations élémentaires effectuées