Chapter 2 Network Models
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CHAPTER 2 Network Models Q1. List the layers of the Internet model? 1. The Internet model, include physical, data link, network, transport, and application layers. Q2. What are the responsibilities of the data link layer in the Internet model? 2. The data link layer is responsible for a. framing data bits b. providing the physical addresses of the sender/receiver c. data rate control d. detection and correction of damaged and lost frames Q3. What are the responsibilities of the network layer in the Internet model? Q4. What are the responsibilities of the transport layer in the Internet model? 4. The transport layer oversees the process-to-process delivery of the entire message. It is responsible for a. dividing the message into manageable segments b. reassembling it at the destination c. flow and error control Q5 What are the responsibilities of the application layer in the Internet model? 5. The application layer services include file transfer, remote access, shared database management, and mail services. Q6. Match the following to one or more layers of the OSI model: a. Reliable process-to-process message delivery b. Route selection c. Defines frames d. Provides user services such as e-mail and file transfer e. Transmission of bit stream across physical medium 6. a. Reliable process-to-process delivery: transport layer b. Route selection: network layer c. Defining frames: data link layer d. Providing user services: application layer e. Transmission of bits across the medium: physical layer Q7. Match the following to one or more layers of the OSI model: b. Flow control c. Interface to transmission media d. Provides access for the end user
Q8. Match the following to one or more layers of the OSI model: a. Format and code conversion services b. Establishes, manages, and terminates sessions c. Ensures reliable transmission of data d. Log-in and log-out procedures e. Provides independence from differences in data representation
a. Format and code conversion services: presentation layer b. Establishing, managing, and terminating sessions: session layer c. Ensuring reliable transmission of data: data link and transport layers d. Log-in and log-out procedures: session layer e. Providing independence from different data representation: presentation layer Q9. Match the following to one or more layers of the OSl model: a. Communicates directly with user's application program b. Error correction and retransmission c. Mechanical, electrical, and functional interface d. Responsibility for carrying frames between adjacent nodes
another checking mechanism at the transport layer? 10. The errors between the nodes can be detected by the data link layer control, but the error at the node (between input port and output port) of the node cannot be detected by the data link layer.
11. (see page no. 46 and 47) \Chapter 11: Data Link Control (المقرر من 307 الى 323 فقط) Q1) explain the Different Types of Framing given an Examples? (Answer in page No 308, 309, 310) Q2) Minton the different type of noisy and noiseless channels with diagram? ( Answer in page No 312) Q3) Explain the Stop-and-wait ARQ protocol with digram? (Answer in page No 318, 319, 320) CHAPTER 13 Local Area Networks: Ethernet Q1. Draw 802.3 MAC frame Format . Q2. What is the difference between a unicast , multicast, and broadcast address? 2. A multicast address identifies a group of stations; a broadcast address identifies all stations on the network. A unicast address identifies one of the addresses in a group. Q3. What is the relationship between a switch and a bridge? 3. A layer-2 switch is an N-port bridge with additional sophistication that allows faster handling of packets. Q4. Compare the data rates for Standard Ethernet, Fast Ethernet, Gigabit Ethernet, and Ten-Gigabit Ethernet. Q5. What is the hexadecimal equivalent of the following Ethernet address? 01011010 00010001 01010101 00011000 10101010 00001111 Q6. Define the type of the following destination addresses: a. 4A:30:10:21:10:1A b. 47:20:1B:2E:08:EE c. FF:FF:FF:FF:FF:FF Q7. An Ethernet MAC sublayer receives 1510 bytes of data from the upper layer. Can the data be encapsulated in one frame? If not, how many frames need to be sent? What is the size of the data in each frame? 7. The maximum data size in the Standard Ethernet is 1500 bytes. The data of 1510 bytes, therefore, must be split between two frames. Data size for the first frame: 1500 bytes Data size for the second frame: 46 bytes (with padding).
Q10. An Ethernet MAC sublayer receives 42 bytes of data from the upper layer. How many bytes of padding must be added to the data? CHAPTER 15 Connecting LANs Q1 1. How is a repeater different from an amplifier?
Q2. How is a hub related to a repeater?
Q3 Complete the Five categories of connecting devices. 
CHAPTER 19 Network Layer: Logical Addressing Q1. What is the number of bits in an IPv4 address? What is the number of bits in an IPv6 address? 1. An IPv4 address is 32 bits long. An IPv6 address is 128 bits long. Q2. What are the differences between classful addressing and classless addressing in IPv4? 2. Classful addressing assigns an organization a Class A, Class B, or Class C block of addresses. Classless addressing assigns an organization a block of contiguous addresses based on its needs. Q3. List the classes in classful addressing and define the application of each class (unicast , multicast, broadcast, or reserve). Q4. What is the network address in a block of addresses? How can we find the network address if one of the addresses in a block is given? 4. The network address in a block of addresses is the first address. The mask can be ANDed with any address in the block to find the network address. 5 - Explain the type of Classes with example? س 1- اشرح انواع الكلاسات مع اعطاء امثلة ؟
Examples: Class C: N.N.N.H
IP : 192.1.2.0 Mask: 255.255.255.0 Class B: N.N.H.H
IP : 168.12.0.0 Mask: 255.255.0.0 Class A: N.H.H.H
IP : 100.0.0.0 Mask: 255.0.0.0 6) Write the following address in binary digits? حول العنوان التالي من النظام العشرى الى النظام الثنائي: 172.16.30.56 الحل (لمزيد من المعلومات ص 555) : 10101100.00010000.00011110.00111000
a. 11110111 11110011 10000111 11011101 b. 10101111 11000000 11110000 00011101 c. 11011111 10110000 00011111 01011101 d. 11101111 11110111 11000111 00011101 8. a. Class E (first four bits are 1s) b. Class B (first bit is 1 and second bit is 0 c. Class C (first two bits are 1s and the third bit is 0) d. Class D (first three bits are 1s and the fourth bit is 0) Q9) In a block of addresses, we know the IP address of one host is 25.34.12.56/16. What are the first address (network address) and the last address (limited broadcast address) in this block? 9. With the information given, the first address is found by ANDing the host address with the mask 255.255.0.0 (/16). The last address can be found by ORing the host address with the mask complement 0.0.255.255. The first address 25.34.0.0 The last address 25.34.255.255 Q10) An organization is granted the block 192.168.1.0/8. The administrator wants to create 32 fixed-length subnets. a. Find the subnet mask. b. Find the number of addresses in each subnet. c. Find the first and last addresses in subnet 192.168.1.8. d. Find all the host addresses in subnet 192.168.1. . الحل : ( نستخدم هذه الطريقة في حالة عدد الشبكات الفرعية متساوي) From formula : No of Subnets = 2n , n is the number bits that borrowed from the host 32 = 2n ==> n = 5, From formula : No of hosts = 2x -2, n is the number bits that remained for the host Then in the host port of class C Class is: 128 64 32 16 8 4 2 1 Network (حدود الشبكة) host The network will be: ( عدد الشبكات الفرعية هي) 192.168.1.0 192.168.1.8 192.168.1.16 192.168.1.24 .. .. … 192.168.1.248 Subnet Mask ; 255.255.255.248 اذا فتحنا احد هذه الشبكات الفرعية فان (كل شيكة تحوى على 6 عناوين ) 192.168.1.8 192.168.1.8 Network ID 192.168.1.9 host 192.168.1.10 host 192.168.1.11 host 192.168.1.12 host 192.168.1.13 host 192.168.1.14 host 192.168.1.15 Broadcast ID
Q11) An organization is granted the block 16.0.0.0/8. The administrator wants to create 500 fixed-length subnets. a. Find the subnet mask. b. Find the number of addresses in each subnet. c. Find the first and last addresses in subnet 1. d. Find the first and last addresses in subnet 500. الحل ( كما في السئول السابق مع الاختلاف في الكلاس) CHAPTER 20 Network Layer: Internet Protocol Q1 Draw IPv4 datagram format. Q2 An IPv4 packet has arrived with the first few hexadecimal digits as shown . 0x45000028000100000102 . . . How many hops can this packet travel before being dropped? The data belong to what upper-layer protocol. Q3 In an IPv4 packet, the value of HLEN is 5, and the value of the total length field is 0x0028. How many bytes of data are being carried by this packet? Q4 An IPv4 datagram has arrived with the following information in the header (in hexadecimal): Ox45 00 00 54 00 03 58 50 20 06 00 00 7C 4E 03 02 B4 OE OF 02 a. Is the packet corrupted? b. Are there any options? c. Is the packet fragmented? d. What is the size of the data? e. How many more routers can the packet travel to? f. What is the identification number of the packet? g. What is the type of service? Let us first find the value of header fields before answering the questions: VER = 0x4 = 4 HLEN =0x5 = 5 4 = 20 Service =0x00 = 0 Total Length = 0x0054 = 84 Identification = 0x0003 = 3 Flags and Fragmentation = 0x0000 D = 0 M= 0 offset = 0 Time to live = 0x20 = 32 Protocol = 0x06 = 6 Checksum = 0x5850 Source Address: 0x7C4E0302 = 124.78.3.2 Destination Address: 0xB40E0F02 = 180.14.15.2 We can then answer the questions: a. If we calculate the checksum, we get 0x0000. The packet is not corrupted. b. Since the length of the header is 20 bytes, there are no options. c. Since M = 0 and offset = 0, the packet is not fragmented. d. The total length is 84. Data size is 64 bytes (84 20). e. Since the value of time to live = 32, the packet may visit up to 32 more routers. f. The identification number of the packet is 3. g. The type of service is normal. Q5. What is the difference between the delivery of a frame in the data link layer and the delivery of a packet in the network layer? The delivery of a frame in the data link layer is node-to-node. The delivery of a packet at the network layer is host-to-host. Q6 The value of HLEN in an IPv4 datagram is 7. How many option bytes are present? Q7. The size of the option field of an IPv4 datagram is 20 bytes. What is the value of HLEN? What is the value in binary? If the size of the option field is 20 bytes, then the total length of the header is 40 bytes (20 byte base header plus 20 bytes of options). The HLEN field will be the total number of bytes in the header divided by 4, in this case ten (1010 in binary). Q8. An IPv4 datagram is carrying 1024 bytes of data. If there is no option information, what is the value of the header length field? What is the value of the total length field? Since there is no option information, the header length is 20, which means that the value of HLEN field is 5 or 0101 in binary. The value of total length is 1024 + 20 or 1044 (00000100 00010100 in binary). Q9. Table 20.5 lists the MTUs for many different protocols. The MTUs range from 296 to 65,535. What would be the advantages of having a large MTU? What would be the advantages of having a small MTU? Advantages of a large MTU: ■ Good for transferring large amounts of data over long distances ■ No fragmentation necessary; faster delivery and no reassembly ■ Fewer lost datagrams ■ More efficient (less overhead)
■ Good for transferring time-sensitive data such as audio or video ■ Better suited for multiplexing Q10. An IPv4 datagram arrives with fragmentation offset of 0 and anM bit (more fragment bit) of O. Is this a first fragment, middle fragment, or last fragment? If the M (more) bit is zero, this means that the datagram is either the last fragment or the it is not fragmented at all. Since the offset is 0, it cannot be the last fragment of a fragmented datagram. The datagram is not fragmented CHAPTER 21 Network Layer: Address Mapping And Error Reporting Q1. Is the size of the ARP packet fixed? Explain. The size of an ARP packet is variable, depending on the length of the logical and physical addresses used. Q2 What is the size of an Ethernet frame carrying an ARP packet if The size of the ARP packet is 28 bytes? Since the size of the ARP is 28 bytes. We need to pad the data to have the minimum size of 46. The size of the packet in the Ethernet frame is then calculated as 6 + 6 + 2 + 46 + 4 = 64 bytes (without preamble and SFD). Q3. What is the minimum size of an IPv4 packet that carries an ICMPv4 packet? What is the maximum size? Directory: 2010 2010 -> Through the Roof 2010 -> 2004 ieee international topical meeting on microwave photonics technical digest 2010 -> The petition and case system 2010 -> Hr 116 Application for Employment with Hills and Dales 2010 -> Polimaster ltd V. Rae systems inc polimaster ltd.; Na&se trading co., Limited, Plaintiffs-Appellants 2010 -> The tandem project 2010 -> Cape Lookout National Seashore Historic Resource Study By 2010 -> Cape Lookout National Seashore Historic Resource Study By 2010 -> Ap u. S. History presidents list the Young Republic, 1788-1815 George Washington, 1789-1797 Download 74.59 Kb. Share with your friends:
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