Options:
A) A student is using a classroom VoIP phone to call home. The unique identifier burned into the phone is a transport layer address used to contact another network device on the same network.
B) A student is playing a short web-based movie with sound. The movie and sound are encoded within the transport layer header.
C) A student has two web browser windows open to access two websites. The transport layer ensures the correct webpage is delivered to the correct browser window.
D) A corporate worker is accessing a web server located on a corporate network. The transport layer formats the screen so the webpage appears properly no matter what device is being used to view the website.
Correct Answer: C) A student has two web browser windows open to access two websites. The transport layer ensures the correct webpage is delivered to the correct browser window.
Let’s delve into each option to understand why option C is the accurate answer when considering the functions of the transport layer in network communication, and why the other options are not.
Option A) A student is using a classroom VoIP phone to call home. The unique identifier burned into the phone is a transport layer address used to contact another network device on the same network.
Option A is incorrect as it misunderstands the role of the transport layer in network communication. The description points towards a lower layer function, specifically the data link layer. The unique identifier mentioned is more likely a MAC address, a hardware address associated with network interfaces, not the transport layer.
The transport layer is primarily concerned with end-to-end communication between applications. It manages data segmentation, reassembly, and reliable data transfer between two endpoints. It does not handle hardware-level identification for devices on the same network; that’s the realm of lower layers like the data link layer. The transport layer ensures data reaches the correct application process on a device, not just the device itself within a local network.
Option B) A student is playing a short web-based movie with sound. The movie and sound are encoded within the transport layer header.
This option is also incorrect because it misrepresents the function of the transport layer. The transport layer is not involved in encoding or encapsulating multimedia content such as movies and sound within its headers. Its main job is to provide reliable and ordered data delivery.
Encoding and encapsulating multimedia content are tasks performed by higher layers in the OSI model. The presentation layer handles data encoding, ensuring data is in a usable format for the application layer. The application layer then encapsulates this content within protocols like HTTP or RTP for web-based streaming. The transport layer then takes this application data and segments it for network transmission, adding headers for control and reliability, but not for encoding the media itself.
Option D) A corporate worker is accessing a web server located on a corporate network. The transport layer formats the screen so the webpage appears properly no matter what device is being used to view the website.
Option D is incorrect because it confuses the responsibilities of the transport layer with those of the presentation and application layers. Screen formatting and ensuring web pages display correctly across different devices are not functions of the transport layer.
These display-related tasks are handled by higher layers. The presentation layer is responsible for data formatting and presentation, ensuring data is in a format that the application layer can understand and display correctly. The application layer, with protocols like HTTP, dictates how web content is structured and interpreted by browsers for display. The transport layer’s responsibility is to ensure reliable data transfer between the corporate worker’s device and the web server, not to manage how the webpage is rendered on the screen.
Option C) A student has two web browser windows open to access two websites. The transport layer ensures the correct webpage is delivered to the correct browser window.
Option C is the correct answer as it accurately describes a core function of the transport layer: managing communication sessions and ensuring correct data delivery to the appropriate application or process. In this scenario, each browser window represents a separate application process requesting data.
Here’s a detailed explanation of why Option C is accurate:
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Multiple Application Sessions: When a student uses two browser windows to access different websites, each window initiates a distinct communication session. These sessions are differentiated using port numbers. The transport layer utilizes these port numbers to keep the traffic from each website separate.
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Port Numbers for Demultiplexing: The transport layer uses port numbers to identify the correct application or process for incoming data. Each browser window, acting as a client application, uses a unique port number for communication. When data from the web servers arrives at the student’s computer, the transport layer examines the destination port number in the transport layer header to direct the data to the correct browser window. This process is known as demultiplexing.
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Session Management: The transport layer is responsible for managing these end-to-end communication sessions. It establishes, maintains, and terminates connections as needed. For each browser window, the transport layer manages a separate session, ensuring that data is correctly routed between the specific browser window and its corresponding web server.
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Reliable Data Delivery: Beyond just directing traffic, the transport layer also provides reliable data delivery mechanisms. Protocols like TCP (Transmission Control Protocol) at the transport layer ensure that data packets are delivered in order, without errors, and without loss. This reliability is crucial for web browsing, ensuring that web pages load completely and correctly in each browser window.
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Preventing Data Mix-Up: Without the transport layer’s function of managing sessions and using port numbers, data from different websites could get mixed up and delivered to the wrong browser window. The transport layer prevents this by ensuring each application process receives only the data intended for it.
In conclusion, Option C precisely illustrates a key function of the transport layer – ensuring that data is delivered to the correct application (in this case, the correct browser window) through session management and port addressing. The other options describe functionalities that belong to different layers of the OSI model, highlighting the importance of understanding the specific roles of each layer in network communication.
Smirti
(Founder of Management Notes)MBA,BBA.I am Smirti Bam, an enthusiastic edu blogger with a passion for sharing insights into the dynamic world of business and management through this website.
I hold a MBA degree from Presidential Business School, Kathmandu, and a BBA degree with a specialization in Finance from Apex College,
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