CN1260 Client Operating System

1. CN1260 Client Operating System Kemtis Kunanuraksapong MSIS with Distinction MCT, MCITP, MCTS, MCDST, MCP, A+

2. Agenda • Chapter 2: Resolving IP Connectivity Issues • Quiz • Exercise

3. Connecting to a Network • Ethernet • Unshielded twisted-pair (UTP) cabling • RJ-45 connectors • 100 Mb/s or 1 Gb/s connections for Ethernet • When there is a connectivity issue: • Check the cable • Look at the indicator lights on the NIC, switch • On the switch or hub, make sure that the switch or hub has power and is turned on.

4. TCP/IP Protocol Suite • Transmission Control Protocol/Internet Protocol • Subnet • Subdividing TCP/IP networks into smaller groupings • Subnet mask • Used to identify which network the TCP/IP host resides on • Default gateway • Allows a host to communicate with devices that reside on a remote network or location

5. Host and IP addresses • A host • Any device that connects directly to a network • Computers, network printers, routers, layer 3 switches, managed switches, and any other device that has a network card or interface • Internet Protocol (IP) address • A logical address and numerical label that is assigned to a device that is connected to a computer network

6. IP Address • IPv4 is The most commonly used version used today • Based on 32-bits (four bytes, or octets) • 232 (4,294,967,296) possible addresses • IPv4 addresses are commonly represented using what is called dotted-decimal notation: • 10.27.3.1 • 192.1.120.84 • 192.5.18.102 • IPv6 addresses, which are based on 128-bit addresses. • Since each bit doubles the number of available addresses, the 128-bit addresses allow up to 3.403 × 1038addresses

7. Classful Addressing • Each network class had a different maximum number of nodes • The first one to four bits identified the network class, and the remaining bits comprised the network and host address fields • Class A • Class B • Class C • See Table 2-1 on Page 32

8. Subnet Mask • Logical partitioning of an organization’s network address range into smaller blocks • Network Address (Enterprise/corporation): • 16.52.0.0/16 • Site 1 has network address of: • 16.52.1.0/24 • Site 2 has network address of: • 16.52.2.0/24

9. Classless Inter-Domain Routing (CIDR) • The number of masked bits is specified with the CIDR notation • Variable-length subnet masking (VLSM) • Example: • 10.0.0.0/10 • 10 bits masked • 22 bits for host numbering

10. Network Address Translation (NAT) • Hosts using private network addresses can communicate with public networks only by using network address translation (NAT) • Enables routing by mapping their private network address to a different, routable network address.

11. Private Addresses • Reserved addresses not allocated to any specific organization • Not routable on the Internet, you must use a NAT gateway or proxy server to convert between private and public addresses • 10.0.0.0 – 10.255.255.255 • 172.16.0.0 – 172.31.255.255 • 192.168.0.0 – 192.168.255.255

12. IPv6 Addressing • IPv6 addresses are 128 bits in length and expressed in hexadecimal notation • 2001:0db8:85a3:08d3:13 • 19:8a2e:0370:7334 • If an IPv6 address contains a series of sequential zeroes, the address can be shortened • 2001:0000:0000:0000:0000:0000:0000:7334 • 2001:0:0:0:0:0:0:7334 • 2001::7334

13. IPv6 Addressing • First 64 bits is the network address • First 48 bits is network prefix • Next 16 bits are used for subnetting • Second 64 bits is the host address • Generated by MAC address

14. IPv6 Addressing • Unicast addressing can be divided into: • Global unicast address • Routable on the IPv6 portion of the Internet • Link-local addresses • Private non-routable addresses (LAN only) • Unique local addresses • Meant for private addressing, with the addition of being unique, so that joining two subnets does not cause address collisions.

15. Default Gateway • A default gateway is a device, usually a router, which connects the local network to other networks • When you need to communicate with a host on another subnet, you forward all packets to the default gateway

16. Name Resolution • Form of naming service that translate logical names, which are easier to remember, to those logical addresses

17. HOST and LHMOST Files • Hosts • Used with domain/host names associated with DNS • Lmhost • Used with NetBIOS/Computer names associated with WINS files • In Windows, both of these files are located in the C:\Windows\system32\drivers\etc folder • See Figure 2-2 on Page 36

18. Domain Name System (DNS) • A hierarchical client/server-based distributed database management systems that translates domain/host names to an IP address • Use FQDN to translate hostname to IP

19. Windows Internet Name Service (WINS) • WINS translates from NetBIOS (computer name) to specify a network resource

20. Network and Sharing Center • Provides real-time status information about your network. • It can be used to configure and manage your network connections • It can also be used to help troubleshoot network connectivity problems • See Figure 2-3 on Page 38

21. Managing Network Discoveryand Sharing Services • The Network and Sharing Center also allows you to configure certain network services such as network discovery and sharing. These settings include: • Network discovery • File and printer sharing • Public folder sharing • Media streaming • Password protected sharing

22. Ports • A host uses ports to identify which packets belong to a network service or program. • 65,535 TCP ports • 65,535 UDP ports • Common ports: • DNS: TCP/UDP port 53 • FTP: TCP port 20 and 21 • HTTP: TCP port 80 • HTTPS: TCP port 443 • SMTP: TCP/UDP port 25 • Telnet: TCP/UDP port 23

23. Troubleshooting IP Network Problems • If the problem still exists, you can also use the following command-line tools: • Ipconfig(/all, /flushdns, /renew) • ping • tracert • pathping • netstat • telnet • nslookup

24. Assignment • Submit these before class over on Thursday • Fill in the blank • Multiple Choice • True / False • Submit these before class start on Monday • Case scenarios 2-1 • Lab 2