ccna - the beginnings

Wählen Sie die richtige Aussage zum UDP-Protokoll (User Datagram Protocol) aus. a- Der UDP-Header enthält die Felder: Quellport, Zielport, UDP-Länge und UDP-Prüfsumme. B- UDP führt beim Empfang eines falschen Segments eine erneute Übertragung durch. c- UDP führt eine Flusskontrolle zur Überlastungskontrolle durch. D- UDP überträgt Segmente, die aus einem 16-Byte-Header bestehen, gefolgt von der Nutzlast. e- Es handelt sich um ein verbindungsorientiertes Transportprotokoll.

About error detection, parity, checksum, and CRC codes ( ) The CRC technique, or Cyclic Redundancy Check, consists of adding a sequential number and an error correction code called CRC, generated from an algorithm that is applied to the header and payload data. ( ) They aim to guarantee reliability in the transmission and reception of data. ( ) Checksum also recovers data transmitted in error. The statements are, respectively,. V – F – F. V – V – V. V – V – F. F – V – V. V – F – V.

Select the correct alternative that identifies the fields used in the fragmentation of IPv4 protocol packets. A= TTL, protocol and header checksum. B= Identification, options and fragment offset. C=Identification, fragment offset and TTL. d- Options, fragment offset and TTL. E= TTL, header checksum and identification.

When a browser wants a web page, it sends the name of the desired page to the server using HTTP. Select the alternative that correctly corresponds to this layer?. A= Presentation layer. B= Application layer. C= Transport layer. d- Data link layer.

The layer responsible for establishing, managing, and terminating connections between applications on different devices, for a given communication period, and ensuring that communications can be established, maintained, and terminated appropriately. What is the layer?. A= Presentation layer. b- Session layer. c- Physical layer. d- Network layer.

Select the option that correctly corresponds to the concept of “they have a very thin fiber core, generally with a diameter of 9 µm, which allows the transmission of a single ray of light in a single direction. This type of cable is used in long-distance networks, where it is necessary to transmit high-speed signals over long distances.”. a- Unshielded Twisted Pair (UTP) Cable. b- Single-mode fiber optic cables. c= Shielded Twisted Pair Cable (STP). D- Coaxial cable.

Two analysts are discussing the implementation of the STP protocol and come across the term root, which is used in different contexts in the STP protocol to designate. a- the bridge in the network that serves as the central point in the spanning tree, called the root bridge, and the port on each device that provides the most efficient path to the root bridge, called the root port. B= the interface that does not participate in frame forwarding, known as the root port, and the first state the bridge transitions to after the blocking state, known as the root state. c= the network link that serves as a backup in case of failure, known as the root link, and the switch elected as the backup, which is elected as the root primary. D=the interface that does not participate in frame forwarding, known as the root port, and the switch with the highest configured priority value, known as the root bridge. E- the interface that receives only BPDUs, known as the root port, and the switch with the highest configured priority value, known as the root bridge.

During data transmission, digital signals suffer from noise that can introduce errors into the binary bits that go from the sender to the receiver. The technique used to detect errors in data transmission in a communication network is: a- Checksum. B= Modulation. c=Encryption. d-Multiplexing.

The IPv4 protocol header has a field called header checksum. When an IPv4 datagram arrives at a router, but the checksum calculated by the router is different from the contents of the field, what happens is: A- The datagram is fragmented into smaller pieces, and each piece is forwarded independently. B= The datagram is forwarded normally to its final destination, if it is on the same network as the router, or to the next router in the path. C= An ICMP echo request message is sent back to the datagram's source IP address by the router. D= The datagram is discarded by the router, leaving it to a higher-layer protocol, if applicable, to arrange for it to be resent. E- Parity bits present in the IPv4 header allow errors in the datagram, detected by the checksum, to be corrected in the router itself.

There are several protocols that can be used in the transport layer of the TCP/IP conceptual model. Select the option below that CORRECTLY relates the protocol used in the transport layer with its functionality. A- UDP (User Datagram Protocol) is a connection-based and reliable transport protocol. It adds additional control to IP delivery services and implements interprocess communication. B- SCTP (Stream Control Transmission Protocol) is a new transport layer protocol that, like UDP, is unreliable and not message-oriented. C= TCP (Transmission Control Protocol), like UDP, is a connection-oriented protocol; it creates a virtual connection between two TCP processes for data transmission. In addition, TCP implements flow and error control mechanisms in the transport layer. D- UDP does not implement error control mechanisms, except for the checksum. This means that the sender does not know if a message was lost or duplicated. When the receiver detects an error through the checksum, the user datagram is discarded imperceptibly. E- TCP is a reliable, connection-oriented protocol that combines the best features of UDP and SCTP. It preserves message delimiters while detecting lost, duplicated, or out-of-order messages.