TASK 4: OSI Reference Model versus TCP/IP Reference Model
OSI Reference Model
OSI open system reference model or OSI Reference Model for open systems administration is a system structural model created by the International Organization for Standardization (ISO) in Europe in 1977. OSI itself remains for Open System Interconnection. This model is likewise called the “OSI seven layer display” show (OSI seven layer demonstrate).
1. Application Layer: Application or administration (benefit) that performs information correspondence process, for example, Electronic Mail, File Transfers, program and others. illustration: FTP, HTTP, SMTP, DNS, TFTP, Telnet
2. Presentation Layer:
• Ensure information can be perused by the framework accepting information and determine the organization of information sent or got.
• Define the information structure
• Set the sentence structure of information exchange for Application Layer.
3. Session Layer
• Build (set up), (oversee), and stop (end) the (session) between applications.
4. Transport Layer
• Determine the strategy and unwavering quality of conveyance (Transport) information between has, eg: TCP or UDP technique
• Establish, keep up, and end Virtual Circuits between hosts or systems.
• Data Fault Detection and set the (recuperation) data transmitted information, by asking for back to the sending has, information is harmed or mistake.
5. Network Layer
• Set the way of information transmission between end-frameworks.
• Routing Settings.
• More to intelligent tending to settings.
6. Data Link Layer
• Set the way toward sending information through media
• Determine physical tending to (Physical Addressing), organize topology, blunder notice, and stream control.
• More on physical tending to settings.
7. Physical Layer
• The way toward changing over computerized information to simple (power voltage) or the other way around.
TCP/IP Reference Model
Description & Explanation:
TCP/IP show is a demonstrating utilizing convention display, in this model is clarified what occurs in each layer convention. TCP/IP show has 4 layer, that is:
1. Application Layer: On this layer is encoded and furthermore the control discourse. The application layer is in charge of how the information imparted over the system is shown to the client.
2. Transport layer: In this layer, the information to be transmitted will be portioned into littler bundles, and afterward send them to Internet layer. TCP takes a shot at this layer.
3. Internet Layer: In this layer the portion is epitomized into parcels and after that wrapped with IP coherent address. Web layer additionally happens the assurance of the best way to the goal
4. Network Access: Bundles that go into this layer are typified again with the physical address (physical address) of the MAC address, and afterward encoded into the media and transmitted to the goal.
Comparison Between OSI Model & TCP/IP Model
Comparison amongst OSI and TCP/IP models include:
1. The OSI layer has 7 layers, and TCP/IP just has 4 layers.
2. The TCP/IP layer is “Protocol Specific”, while OSI layer is an Independent Protocol.
3. The top layers of the OSI layers are application, presentation, and session becoming exhibited in 1 layer of TCP/IP layers.
4. All the standards used on TCP/IP systems can be gotten safely from different PCs in internet, not at all like OSI.
5. The advancement of ISO/OSI wavered not at all like TCP/IP.
6. For the long term, the likelihood of TCP/IP will turn into the world’s standard PC organize, not at all like the OSI.
7. OSI developed its model based on theory, while TCP built up its model after it has been actualized.
8. TCP/IP consolidates OSI introduction and session layers into the application layer.
9. TCP/IP consolidates OSI data link and physical layers into a single layer.
10. TCP/IP is less complex with 4 layers.
11. TCP/IP is more credible because of its protocol. No network is worked with the OSI protocol, in spite of the fact that everybody utilizes the OSI model to manage their psyches.
TASK 5: Networking devices
Repeaters It is an electronic tool that connects two parts or “legs” of the network cable. It also can be described as a tool used to recreate a signal. They’re primarly used in transmission systems to replicate not only digital, but also analog signals distorted or deformed by loss of transmission. These analog repeaters usually can just amplify only the signal while the digital ones can regenerate a signal the nearest to its original quality as possible. It takes the signals and regenarate and retime them to be sent to the other cable legs. It does it by receiving a digital signal on an optical transmission medium and extend the transmission so that the signal can reach further distances or can be “heard” by other devices that are located in the other side when divided by an obstruction.
Switches A switch is a computer device used, also, to connect multiple computers together on a local network, also called LAN. They enable different connection points or nodes of a LAN to communicate straight to each o ther in a softer but, also, efficient way.
Every switch port owns a different collision domain. The switch performs at the second layer on the OSI Layer model. At this layer, data signals are formatted in frames.
Router Router is a small layer 3 device which transfers data packet from one logical network segment to another. It’s called a layer 3 because it connects two or more networks and it also runs in the OSI layer. The router keeps track of the path that packets can use as they move along the network by recording it. These records are stored in a DB table known as ‘routing table’. A routing table can be statically or dynamically built.
Gateway Gateway is used to transfers the packets that are aimed for remote networking from local network. Until default gateway address is configured within the host, every packet should contain a default gateway address. It is the address of the gateway device. If a packet does not encounter its destination address in a local network, then it would need the help of a gateway device to find the destination address in remote network.
(Wireless Access Point) WAP is a group of communication protocols used to standardize/regulate the manner that wireless devices can be employed for Internet access. 1. A WAP device user requests content from the application server.
2. The request gets to the gateway first. Once there, it does the protocol translation or decoding and coding from WAP to HTTP and routes the HTTP request to the destination server.
3. The server returns WML output and adds HTTP headers to the gateway, depending on which types of pages are requested: dynamic or static.
4. The gateway turns WML and HTTP into binary form to preserve bandwidth. Then, in return, it delivers a WAP response to the user.
5. The browser that’s located inside the WAP device depicts the WML and displays the contents.