Communication Systems and Computer Networks Part 5

<p>Connectionless design (B)</p> Signup and view all the answers

<p>Internet Protocol (IP) (C)</p> Signup and view all the answers

<p>56-kbps (D)</p> Signup and view all the answers

<p>ARPANET (D)</p> Signup and view all the answers

<p>Connectionless networks can dynamically reroute packets. (C)</p> Signup and view all the answers

<p>They allow hardware routers to operate at high speeds. (B)</p> Signup and view all the answers

<p>By following a fixed path for all cells. (D)</p> Signup and view all the answers

<p>ATM does not guarantee any form of error correction. (D)</p> Signup and view all the answers

<p>155 Mbps (C)</p> Signup and view all the answers

<p>Their order is guaranteed, but delivery is not. (D)</p> Signup and view all the answers

<p>They are organized using lines and switches like traditional WANs. (A)</p> Signup and view all the answers

<p>They prevent long-duration line blocking, aiding quality of service. (A)</p> Signup and view all the answers

<p>Guaranteed order delivery with potential packet loss. (B)</p> Signup and view all the answers

<p>To enable connection-oriented public data networking (A)</p> Signup and view all the answers

<p>Error control mechanisms (A)</p> Signup and view all the answers

<p>Interconnecting LANs at various company offices (B)</p> Signup and view all the answers

<p>It is a connection-oriented network (B)</p> Signup and view all the answers

<p>X.25 includes error correction mechanisms (B)</p> Signup and view all the answers

<p>Dependency on multiple connection establishments (B)</p> Signup and view all the answers

<p>1980s (A)</p> Signup and view all the answers

<p>It would reduce costs associated with billing and record keeping (A)</p> Signup and view all the answers

The Internet's predecessor, the ARPANET, was designed to withstand nuclear attacks by allowing data to be transmitted through multiple, independent paths.

The original ARPANET infrastructure used minicomputers called IMPs (Interface Message Processors) connected by 56-kbps lines to ensure reliable communication. Each IMP ideally had connections to at least two other IMPs.

The Internet's early development involved creating a network that could continue functioning even if multiple parts were destroyed. This requirement led to the establishment of a connectionless design.

Each packet in a connectionless network travels independently of other packets. If a packet fails during a session, the system dynamically finds alternate paths to reach the destination. This ensures continued communication even during disruptions.

The ARPANET's design prioritized fault tolerance, making it resistant to network disruptions. This was a primary focus over cost-efficiency, which led to less emphasis on billing practices.

The Internet's connectionless design, often attributed to the ARPANET's early focus on fault tolerance, is a defining feature of its architecture. This design allows for flexibility and resilience in the face of network failures.

Connection-oriented networks, like X.25, Frame Relay, and ATM, prioritize reliable, dedicated connections between devices. These networks are designed to ensure data is delivered in a specific sequence and order.

The development of networking technologies has seen a constant debate between proponents of connectionless (datagram) networks, like the Internet, and connection-oriented networks, each striving for a better approach to data delivery.

A connection-oriented public data network developed in the 1970s, X.25 was used for connecting computers by establishing a connection like a telephone call.

Each X.25 connection is assigned a unique number to identify and track data packets during transmission.

X.25 packets consist of a simple header containing the connection number, sequence number, acknowledgment number, and miscellaneous information, along with up to 128 bytes of data.

A type of network that replaced X.25 in the 1980s, frame relay is connection-oriented but doesn't handle errors or control data flow. It acts like a wide area LAN connecting offices.

Frame relay is efficient for connecting LANs in different offices, acting as a high-speed network for sharing data between locations.

ATM (Asynchronous Transfer Mode) is a sophisticated, connection-oriented network vital for high-speed data transmission. The name comes from the fact that it doesn't use synchronous transmission like traditional telephone systems.

ATM is designed for transmitting various types of data, including voice, video, and text, at a high speed, and is widely used in fiber optic networks.

Unlike frame relay, ATM has built-in mechanisms for error control and flow control, ensuring data arrives correctly and efficiently.

ATM (Asynchronous Transfer Mode) networks use fixed-size cells, typically 53 bytes, for data transmission. This approach is faster than variable-length packets because it allows hardware-based routing, eliminating the need for software processing.

ATM networks are designed to handle real-time applications like television broadcasts. Their hardware can efficiently copy incoming cells to multiple destinations, ensuring a smooth distribution of data.

The fixed-size cells in ATM networks do not occupy lines for long, making it easier to guarantee the quality of service. Data flow is less disrupted, leading to more predictable performance.

In ATM, cells are delivered in the order they were sent, even if some cells are lost. This guarantee is more reliable than the Internet, which can lose packets and deliver them out of order.

ATM networks, like traditional WANs, consist of lines and switches (routers) for data transmission. Popular speeds in ATM networks are 155 Mbps and 622 Mbps.

The standard ATM network speed of 155.52 Mbps was selected to support high-definition television (HDTV) transmission. This speed is compatible with AT&T's SONET transmission system.

The 622 Mbps speed in ATM networks was chosen to allow the transmission of multiple 155 Mbps channels over a single line. This efficiently utilizes bandwidth while ensuring capacity for various applications.

ATM networks are designed to prioritize data delivery, ensuring that information reaches its destination in a specific sequence. This approach contrasts with the Internet's connectionless design, which focuses on flexibility and fault tolerance.