Study Guide. Module Two

Transcription

1 Module Two Study Guide Study Guide Contents Part One -- Textbook Questions Part Two -- Assignment Questions Part Three -- Vocabulary Chapter 4 Data Link Layer What is the function of the data link layer? What is media access control? Compare and contrast controlled access and contention methodologies. In a LAN context, briefly describe noise including white noise and crosstalk. What are three ways of reducing errors and the types of noise they affect? Briefly describe how even parity and odd parity works. Briefly describe how checksum works. How does a CRC work? How does forward error correction work? How does it differ from other error-correction methods? What is Ethernet? What is PPP? What is transmission efficiency? How do information bits differ from overhead bits? Are stop bits necessary in asynchronous transmission? Explain. What is a datalink layer address? Are large frame sizes better than small frame sizes? Explain. Chapter 5 Network and Transport Layers What is the function of the transport layer? What is the function of the network layer? Explain the address and flag fields of a TCP/IP packet. Compare and contrast the three types of addresses used in a network. (Application, Network, MAC) Compare and contrast TCP and UDP. How does TCP establish a session? What is a subnet and why do networks need them? What is a subnet mask?

2 How many hosts are there in a network that has 16 bits in its subnet mask? How does dynamic addressing work? What problems does dynamic addressing solve? What is address resolution? How does TCP/IP resolve URLs into network layer addresses? How does TCP/IP resolve IP addresses into data link layer addresses? What is routing? Compare and contrast connectionless and connection-oriented communications? What is QoS? Why is it useful? Compare and contrast unicast, broadcast, and multicast messages. Why does HTTP use TCP and DNS use UDP? How does static routing differ from dynamic routing? When would you use static routing? When would you use dynamic routing? What is the transmission efficiency of a 10-byte Web request sent using HTTP, TCP/IP, and Ethernet? Assume the HTTP packet has 100 bytes in addition to the 10-byte URL. Hint: Remember from Chapter 4 that efficiency = user data/total transmission size. What is the transmission efficiency of a 1,000-byte file sent in response to aweb request HTTP, TCP/IP, and Ethernet? Assume the HTTP packet has 100bytes in addition to the 1,000-byte file. Hint: Remember from Chapter 4 that efficiency= user data/total transmission size. What is the transmission efficiency of a 5,000-byte file sent in response to a Web request HTTP, TCP/IP, and Ethernet? Assume the HTTP packet has 100 bytes in addition to the 5,000-byte file. Assume that the maximum packet size is 1,200 bytes. Hint: Remember from Chapter 4 that efficiency = user data/total transmission size. Describe the anatomy of a router. How does a router differ from a computer? Chapter 6 Wired and Wireless Local Area Networks What is a local area network? Describe three types of servers. Describe the basic components of a wired LAN. Describe the basic components of a wireless LAN. What types of cables are commonly used in wired LANs? What does a NOS do? Compare and contrast logical and physical topologies? Briefly describe how CSMA/CD works. How do Ethernet switches know where to send the frames they receive? How does Wi-Fi differ from shared Ethernet in terms of topology, media access control, and error control, Ethernet frame? Explain how association works in a WLAN context. What is a site survey and why is it important? How do you decide how many APs are needed and where they should be placed for best performance?

3 Assignment Questions Understanding Switches 1. On which OSI model layer, do switches reside? 2. What information does the first half of the MAC address contain? 3. What information does the last half of the MAC address contain? 4. What access methodology does Ethernet utilize? 5. Briefly explain the difference between managed and unmanaged switches. 6. Compare and contrast full and half duplex. 7. What is a VLAN? Briefly describe its function. 8. What is QOS? Briefly describe an environment where it would be useful? 9. What is the spanning tree protocol? What problem does it prevent? Introduction to DHCP 1. Prior to DHCP, how were IP addresses assigned? 2. What is DHCP scope? Give an example. 3. What is a DHCP lease? 4. How does a DHCP Server respond to a DHCP Discover Request? 5. At what OSI level does DHCP operate? TCP/IP and Subnet Masking 1. What is TCP/IP version 6? 2. What version of TCP/IP will we focus on? 3. What does it mean when we say that TCP/IP is actually a protocol suite? 4. What is a routable protocol? 5. What OSI layer does IP reside upon? 6. What OSI layer does TCP reside upon? 7. In TCP/IP what is windowing? 8. How many bits does an IP v4 address have? 9. In TCP/IP, what is the default gateway? 10. What does a Domain Name Server do? 11. What is Network Address Translation (NAT)? 12. In a TCP/IP address, what is an octet? 13. What is the purpose of a subnet mask? 14. What would the subnet mask be if you wanted to use 8 bits for the network address and 8 bits for subnets? 15. When was the last time that class full addressing was commonly used? 16. What replaced class full addressing? Understanding SOHO Routers 1. What differentiates a SOHO router from an Enterprise Router? 2. When dealing with an ISP, why might you want a static IP address? 3. What functions (services) are normally found in a SOHO router? 4. What does a firewall do? 5. With a SOHO router, why might redundancy be desirable?

4 6. What is a DMZ? Why would a small company want one? 7. In a small office, what would be the disadvantage of using enterprise level routers? Physical Network Segmentation 1. What is a demarc point? 2. What is the significance of a demark point? 3. What is a Main Distribution Frame? 4. What is an Intermediate Distribution Frame? 5. Why use an IDF? 6. In a conventional small network, where would you expect to find the MDF? 7. If you had a network that covered five floors in a building, how many IDF(s) and MDF(s) would you expect to have? 8. What purpose does an IDF serve?

5 Vocabulary Chapter Four Data Link Layer Asynchronous transmission Attenuation Checksum Contention controlled access cross-talk cyclical redundancy check (CRC) efficiency error detection Ethernet (IEEE 802.3) forward error correction frame high-level data link control (HDLC) information bits intermodulation noise line noise logical link control (LLC) media access control media access control (MAC) overhead bits parity bit parity check Point-to-Point Protocol (PPP) polling start and stop bits synchronization synchronous transmission throughput token passing transmission efficiency white noise Chapter Five Network and Transport Layers Access Control List (ACL) Address Resolution Protocol (ARP) application layer address (URL) autonomous systems Border Gateway Protocol (BGP) border router broadcast message Cisco IOS classless addressing connectionless connection-oriented console port data link layer address destination port address distance vector routing Domain Name Service (DNS) dynamic addressing Dynamic Host Configuration Protocol (DHCP) dynamic routing Enhanced Interior Gateway Routing Protocol (EIGRP) exterior routing protocol gateway Interior Gateway Routing Protocol(IGRP) interior routing protocol Internet address classes Internet Control Message Protocol (ICMP) Internet Corporation for Assigned Names and Numbers (ICANN) link state routing multicast message network layer address Open Shortest Path First (OSPF) port address Quality of Service (QoS) Real-Time Streaming Protocol (RTSP) RSS Real-Time Transport Protocol (RTP) Resource Reservation Protocol (RSVP) Routing Information Protocol (RIP) Chapter 6 Wired and Wireless LANs access point (AP) Active Directory Service (ADS) association bus topology Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) collision domain controller Extensible Authentication Protocol (EAP) fiber-optic cable forwarding table frame IEEE layer-2 switch lightweight directory services (LDAP) logical topology network-attached storage (NAS) network operating system (NOS) network profile network segmentation peer-to-peer network physical topology redundant array of inexpensive disks (RAID) shielded twisted-pair (STP) site survey small office, home office (SOHO) software audit software piracy Software Publishers Association (SPA) storage area network (SAN) store and forward switching switch switched Ethernet symmetric multi-processing (SMP) topology twisted-pair cable unshielded twisted-pair (UTP) cable war driving Wi-Fi

6 routing table source port address static routing subnet subnet mask Transmission Control Protocol/Internet Protocol (TCP/IP) unicast message User Datagram Protocol (UDP) Wi-Fi Protected Access (WPA) Wired Equivalent Privacy (WEP) Wireless LAN (WLAN) g n