Advantages and disadvantages of WAN

Advantages and disadvantages of WAN Assumption. The company consist of 4 buildings, one as headquarter which located in Kuala Lumpur, Malaysia and three as branches which located in Jakarta Indonesia, Bangkok Thailand and Manila Filipina. The company consists of 4 departments that are admin staff, IT department, marketing department and human resources department, which have total 40 employees in every office. Each department has 10 employees, which mean every departments room consist of 10 personal computers. LAN architecture will be the same between headquarter and branches. Every building Consist of 3 floors, 1st floors for administrator staff and human resources staff, 2nd floor for IT department and server room and the 3rd floor for marketing and meeting room. Every department has its own peripherals such as printer, scanner, and Photostat machine. Projector will be in meeting room. Have connection to the Internet and connection to each office. Headquarter office has external backup which located in Malaysia nearby headquarter office approximately 2 km, its provide backup for the database. Problem identification. The company does not have network yet. The company does not have DBMS (Database Management System). The company does not have backup yet. Security issues. WAN explanation. There are five sites in the WAN diagram, consist of headquarter office which is located in Kuala Lumpur Malaysia, three branches offices which is located in Thailand Filipina and Indonesia and one external backup which is located nearby headquarter office. The function of external backup is to keep the data as the original data. WAN topology. Basically WAN topology is almost similar with the LAN topology consist of point-to-point topology, ring topology and star topology. There are several advantages and disadvantages for every topology. The advantages and disadvantages of each topology will be shown in table bellow. For this company we suggest to use star topology because it is more s calable, provides shorter data paths between two sites and easy to add new nodes, if someday the company will expand the business by adding new branches in the other country it will easy to add to the existing WAN, the disadvantages of star topology is it has single point of failure at the concentrator routers. To overcome this problem network administrator tend to add some alternatives links between sites. WAN transmission technology. For WAN technologies we will do comparison between three technologies that are leased line, frame relay, X.25 and PPP. For WAN technologies we suggest to use frame relay because it can provide performance similar with the lease line with significantly less cost over long distance. Another reason is reduce internetworking cost because with frame relay required fewer port to access other network, increase performance with reduce complexity and definitely it is cheaper than leased line. Lower cost over long distance makes frame relay is good for this com pany because the branches office located across the country. Technology. For WAN technology we suggest to use VPN (virtual private network). VPN is alternatives technology to replace the more expensive WAN technology. The advantages of VPN that available online on: (http://www.universitydissertations.com/Communications/using-VPN.php) are, provide well security method, less expensive when compare with the WAN technology, reduce setup times, fast network link, simple network topology and productivity improved due to less constraints when compared with other networking methods. And the disadvantage of VPN is limited security for wireless users.

Andrei Sakharov Essay Example | Topics and Well Written Essays - 500 words

Andrei Sakharov - Essay Example In the aftermath of the Second World War, Sakharov researched about the cosmic rays and other nuclear related technologies, thereby playing a prominent role in the development of Soviet’s first megaton-range hydrogen bomb. The same nuclear weapons specialist turned a new leaf, when in early 1950’s, he started proposing peaceful utilization of nuclear technologies like for power generation, and then in 1960’s pushed for the reduction of worldwide nuclear arsenal including Soviet Union’s. In that later period only, Sakharov started writing many books, essays and articles, which reflected on his life, Soviet Union, politics and importantly his views against nuclear weapons. His first as well as his path breaking work is an essay titled Reflections on Progress, Peaceful Coexistence, and Intellectual Freedom, which was published in 1968. In that essay, he took stance against the anti-ballistic missile defense system, which was being planned by both Soviet Union and USA, and in a way criticized the policies of the Soviet establishment. Because of this anti-government stance, the essay was first circulated in ‘samizdat’ (rough copies, which were circulated manually).

Emerency Sevices Managment - Advaced Interactions of Hazardous Research Paper

Emerency Sevices Managment - Advaced Interactions of Hazardous Materials VIII - Research Paper Example investigations like that from T2 laboratories, it becomes evident that the incident was preventable if the laboratory had instituted precautionary measures. Before a factory begins preparing or using any hazardous chemical like methylcyclopentadienyl manganese tricarbonyl or methyl mercaptan, thorough literature review about the chemical should be carried out (Bevelacqua, 2006). Information such as whether the substance is poisonous, flammable, corrosive or oxidizer should be obtained. Besides, the threshold limit and the IDHL values are determined. The IDHL values for chlorine (10 ppm in air) is far below that of methyl mercaptan (150 ppm in air) indicating that chlorine is more poisonous than methyl mercaptan. The factory is supposed to prepare a list of the dangerous chemicals they are handling and the possible dangers likely posed by those chemicals. The list and the risk management plan are submitted to the Environmental Protection Agency (EPA). The risk management plan should contain information about; prevention measures, site activities, action taken in case of an emergency and any plan to improve on safety (Bevelacqua, 2006). T2 laboratory did not have a risk management plan and had not registered with the Environmental Protection Agency. If T2 had complied with this requirement, the runaway exothermic reaction would have been prevented because T2 would have received proper advice from EPA. Preliminary Hazard Analysis (PHA) should be done to determine the particular step in the production process associated with a hazard. T2 noted that an exothermic reaction occurred during the first step (metalation), heat release in the second and the third reaction step was overlooked. In additi on, the laboratory did not carry out hazard and operability study (HAZOP) when they scaled up. Conditions for small scale production may differ with those for large-scale production. It was mandatory for a T2 lab to assess the risks involved in a large scale production of