Network fundamentals – Chapter 6: Addressing the network – Ipv4

Network Fundamentals – Chapter 6 Addressing the Network – IPv4 CCNA Exploration version 4.0 Học viện mạng Bách Khoa - Website: www.bkacad.com 2 Objectives • Explain the structure IP addressing and demonstrate the ability to convert between 8-bit binary and decimal numbers. • Given an IPv4 address, classify by type and describe how it is used in the network • Explain how addresses are assigned to networks by ISPs and within networks by administrators • Determine the network portion of the host address and explain the role of the subnet mask in dividing networks. • Given IPv4 addressing information and design criteria, calculate the appropriate addressing components. • Use common testing utilities to verify and test network connectivity and operational status of the IP protocol stack on a host. Học viện mạng Bách Khoa - Website: www.bkacad.com 3 Labs Học viện mạng Bách Khoa - Website: www.bkacad.com 4 Introduction • Addressing is a key function of Network layer protocols that enables data communication between hosts on the same network or on different networks. • Designing, implementing and managing an effective IPv4 addressing plan ensures that our networks can operate effectively and efficiently. Học viện mạng Bách Khoa - Website: www.bkacad.com 5 IPv4 Addresses Học viện mạng Bách Khoa - Website: www.bkacad.com 6 IP Addressing Structure • 32-bit address is expressed in Dotted decimal • Network portion • Host portion • Octet 6.1.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 7 Binary to Decimal Conversion 6.1.2.1 Positional Notation Học viện mạng Bách Khoa - Website: www.bkacad.com 8 Binary to Decimal Conversion 6.1.2.2 6.1.3 Practice Activity Học viện mạng Bách Khoa - Website: www.bkacad.com 9 Học viện mạng Bách Khoa - Website: www.bkacad.com 10 Decimal to Binary Conversions 6.1.4.1 most-significant bit (msb) Học viện mạng Bách Khoa - Website: www.bkacad.com 11 Decimal to Binary Conversions 6.1.4.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 12 Decimal to Binary Conversions 6.1.4.3 6.1.5 Practicing Decimal to Binary Conversion Học viện mạng Bách Khoa - Website: www.bkacad.com 13 Học viện mạng Bách Khoa - Website: www.bkacad.com 14 Subnet Mask Học viện mạng Bách Khoa - Website: www.bkacad.com 15 Defining the Network and Host Portions • The subnet mask is 32-bit pattern and created by placing – a binary 1 in each bit position that represents the network portion and placing – a binary 0 in each bit position that represents the host portion. • The prefix and the subnet mask are different ways of representing the same thing - the network portion of an address. 6.4.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 16 Defining the Network and Host Portions • 00000000 = 0 • 10000000 = 128 • 11000000 = 192 • 11100000 = 224 • 11110000 = 240 • 11111000 = 248 • 11111100 = 252 • 11111110 = 254 • 11111111 = 255 Học viện mạng Bách Khoa - Website: www.bkacad.com 17 Defining the Network and Host Portions Học viện mạng Bách Khoa - Website: www.bkacad.com 18 Defining the Network and Host Portions Học viện mạng Bách Khoa - Website: www.bkacad.com 19 ANDing • ANDing process: extracts the network address from the IP address. • Logical AND: 1 AND 1 = 1 1 AND 0 = 0 0 AND 1 = 0 0 AND 0 = 0 6.4.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 20 Defining the Network and Host Portions Học viện mạng Bách Khoa - Website: www.bkacad.com 21 The ANDing Process 6.4.3 Học viện mạng Bách Khoa - Website: www.bkacad.com 22 Addresses for Different Purposes Học viện mạng Bách Khoa - Website: www.bkacad.com 23 Type of Address in an IPv4 Network 1. Network address - The address by which we refer to the network. All hosts in a network will have the same network bits. 2. Broadcast address - A special address used to send data to all hosts in the network. The broadcast address uses the highest address in the network range. This is the address in which the bits in the host portion are all 1s. This address is also referred to as the directed broadcast. 3. Host addresses - The addresses assigned to the end devices in the network Three types of addresses 6.2.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 24 Type of Address in an IPv4 Network Học viện mạng Bách Khoa - Website: www.bkacad.com 25 Type of Address in an IPv4 Network Học viện mạng Bách Khoa - Website: www.bkacad.com 26 Type of Address in an IPv4 Network Học viện mạng Bách Khoa - Website: www.bkacad.com 27 Type of Address in an IPv4 Network 6.2.1.2 The prefix length is the number of bits in the address that gives us the network portion. Q/A: Bogon networks Học viện mạng Bách Khoa - Website: www.bkacad.com 28 Học viện mạng Bách Khoa - Website: www.bkacad.com 29 Calculating addresses 6.2.2.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 30 Network, Hosts & Broadcast Addresses 6.2.2.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 31 Types of Communication Unicast: • Is used for the normal host- to-host communication in both a client/server and a peer-to-peer network. • Uses the host address of the destination device as the destination address and can be routed through an internetwork. 6.2.3.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 32 Types of Communication Broadcast: • The process of sending a packet from one host to all hosts in the network • Host processes a broadcast address destination packet like unicast address. • A directed broadcast is sent to all hosts on a specific network. • The limit d broadcast is used for communication that is limited to the hosts on the local network. 6.2.3.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 33 Types of Communication Multicast: • The process of sending a packet from one host to a selected group of hosts. • Multicast transmission is designed to conserve the bandwidth of the IPv4 network. • The multicast clients use services initiated by a client program to subscribe to the multicast group. 6.2.3.3 IP v4 Multicast Address ? Lab 6.2.3.4 Học viện mạng Bách Khoa - Website: www.bkacad.com 34 Học viện mạng Bách Khoa - Website: www.bkacad.com 35 Reserved IPv4 Address Ranges 6.2.4 Q/A: Host Addresses •Which are addresses within the address range used for special purpose ? Học viện mạng Bách Khoa - Website: www.bkacad.com 36 6.2.4 Q/A: Multicast Addresses •Link Local addresses ? •Global scopred addresses ? Học viện mạng Bách Khoa - Website: www.bkacad.com 37 6.2.4 Học viện mạng Bách Khoa - Website: www.bkacad.com 38 Public and Private addresses 6.2.5 Học viện mạng Bách Khoa - Website: www.bkacad.com 39 Public and Private addresses • Private Addresses: are set aside for use in private networks. – 10.0.0.0 to 10.255.255.255 (10.0.0.0 /8) – 172.16.0.0 to 172.31.255.255 (172.16.0.0 /12) – 192.168.0.0 to 192.168.255.255 (192.168.0.0 /16) • Public Addresses: are designed to be used in the hosts that are publicly accessible from the Internet. • Network Address Translation (NAT): is used to translate private addresses to public addresses, be implemented on a device at the edge of the private network. Activity 6.2.5.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 40 Học viện mạng Bách Khoa - Website: www.bkacad.com 41 Special IPv4 Addresses • Network Addresses • Broadcast Addresses • Default Route • 0.0.0.0/0 • Link-Local Addresses • 169.254.0.0 to 169.254.255.255 (169.254.0.0 /16) • These addresses can be automatically assigned • TEST-NET Addresses • The address block 192.0.2.0 to 192.0.2.255 (192.0.2.0 /24) is set aside for teaching and learning purposes. These addresses can be used in documentation and network examples. Unlike the experimental addresses, network devices will accept these addresses in their configurations 6.2.6 Học viện mạng Bách Khoa - Website: www.bkacad.com 42 Special IPv4 Addresses Học viện mạng Bách Khoa - Website: www.bkacad.com 43 Legacy IPv4 Addressing 6.2.7 Classful Addressing Học viện mạng Bách Khoa - Website: www.bkacad.com 44 Legacy IPv4 Addressing • Limits to the Class-based System –Classful allocation of address space often wasted many addresses, which exhausted the availability of IPv4 addresses. Học viện mạng Bách Khoa - Website: www.bkacad.com 45 Legacy IPv4 Addressing • Classless Addressing –Address blocks appropriate to the number of hosts are assigned to companies or organizations without regard to the unicast class. Học viện mạng Bách Khoa - Website: www.bkacad.com 46 Assigning Addresses Học viện mạng Bách Khoa - Website: www.bkacad.com 47 Planning to Address the Network 1. Preventing duplication of addresses: each host in an internetwork must have a unique address. 2. Providing and controlling access: Some hosts provide resources to the internal network as well as to the external network. If the addresses for these resources are not planned and documented, the security and accessibility of the devices are not easily controlled. 3. Monitoring security and performance: As part of the monitoring process, we examine network traffic looking for addresses that are generating or receiving excessive packets. The allocation of these addresses inside the networks should be planned and documented for the purpose of: 6.3.1.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 48 Planning to Address the Network • Within a network, there are different types of hosts: – End devices for users – Servers and peripherals – Hosts that are accessible from the Internet – Intermediary devices Học viện mạng Bách Khoa - Website: www.bkacad.com 49 Planning to Address the Network • An important part of planning an IPv4 addressing scheme is deciding when private addresses are to be used and where they are to be applied. Considerations: 1. Number of devices connected to the network more than public addresses allocated by the network's ISP? 2. Need to be accessed from outside the local network? 3. Supports NAT service? 6.3.1.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 50 Planning to Address the Network Học viện mạng Bách Khoa - Website: www.bkacad.com 51 Planning to Address the Network Học viện mạng Bách Khoa - Website: www.bkacad.com 52 Assigning Addresses • Static Assignment: The network administrator must manually configure the network information for a host. 6.3.2.1 Benefits ? Học viện mạng Bách Khoa - Website: www.bkacad.com 53 Assigning Addresses • Dynamic Host Configuration Protocol (DHCP): enables the automatic assignment of addressing information such as IP address, subnet mask, default gateway, and other configuration information. 6.3.2.2 Benefits ? Học viện mạng Bách Khoa - Website: www.bkacad.com 54 Assigning Addresses to Other Devices 6.3.3 Học viện mạng Bách Khoa - Website: www.bkacad.com 55 Who Assigs the Different Addresses ? • Internet Assigned Numbers Authority (IANA) ( ) is the master holder of the IP addresses. 6.3.4 Học viện mạng Bách Khoa - Website: www.bkacad.com 56 ISPs 6.3.5 Internet Backbone ? Học viện mạng Bách Khoa - Website: www.bkacad.com 57 ISPs: Tier 1 • The primary advantages for customers of Tier 1 ISPs are reliability and speed. • The drawback for Tier 1 ISP customers is its high cost. Học viện mạng Bách Khoa - Website: www.bkacad.com 58 ISPs: Tier 2 • Tier 2 ISPs generally focus on business customers. • These tier 2 ISPs tend to have the IT resources to operate their own services such as DNS, e- mail servers, and web servers. • The primary disadvantage of Tier 2 ISPs, as compared to Tier 1 ISPs, is slower Internet access. Học viện mạng Bách Khoa - Website: www.bkacad.com 59 ISPs: Tier 3 • The focus of these ISPs is the retail and home markets in a specific locale. • While they may have reduced bandwidth and less reliability than Tier 1 and Tier 2 providers, they are often good choices for small to medium size companies. Học viện mạng Bách Khoa - Website: www.bkacad.com 60 Overview of IPv6 6.3.6 Học viện mạng Bách Khoa - Website: www.bkacad.com 61 Overview of IPv6 • Creating expanded addressing capabilities was the initial motivation for developing this new protocol. • Other issues were also considered during the development of IPv6, such as: – Improved packet handling – Increased scalability and longevity –QoS mechanisms – Integrated security Học viện mạng Bách Khoa - Website: www.bkacad.com 62 Overview of IPv6 1. 128-bit hierarchical addressing - to expand addressing capabilities 2. Header format simplification - to improve packet handling 3. Improved support for extensions and options - for increased scalability/longevity and improved packet handling 4. Flow labeling capability - as QoS mechanisms 5. Authentication and privacy capabilities - to integrate security To provide these features, IPv6 offers: Học viện mạng Bách Khoa - Website: www.bkacad.com 63 Overview of IPv6 • IPv6 is not merely a new Layer 3 protocol - it is a new protocol suite. • Because of the increased size of the IPv6 header, it also impacts the underlying network infrastructure. Học viện mạng Bách Khoa - Website: www.bkacad.com 64 Calculating Addresses Học viện mạng Bách Khoa - Website: www.bkacad.com 65 Basic subnetting 6.5.1.1 Formula for calculating subnets • The number of subnets = 2^n (n= the number of bits borrowed) • The number of hosts per network = 2^n -2 (n= number of host bits) Học viện mạng Bách Khoa - Website: www.bkacad.com 66 Học viện mạng Bách Khoa - Website: www.bkacad.com 67 Basic subnetting 6.5.1.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 68 Basic subnetting 6.5.1.3 FLSM vs VLSM •Fixed Length Subnet Mask •Variable Length Subnet Mask Học viện mạng Bách Khoa - Website: www.bkacad.com 69 Học viện mạng Bách Khoa - Website: www.bkacad.com 70 Dividing Networks into Right Sizes 6.5.2.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 71 Dividing Networks into Right Sizes 6.5.2.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 72 Học viện mạng Bách Khoa - Website: www.bkacad.com 73 Subnetting a Subnet 6.5.3 subnetting the subnets Học viện mạng Bách Khoa - Website: www.bkacad.com 74 Subnetting a Subnet Học viện mạng Bách Khoa - Website: www.bkacad.com 75 6.5.4 Determining the Network Address Học viện mạng Bách Khoa - Website: www.bkacad.com 76 6.5.5 Calculating the Number of Hosts Học viện mạng Bách Khoa - Website: www.bkacad.com 77 6.5.6 Determining Valid Addresses for Hosts Lab 6.5.7 Học viện mạng Bách Khoa - Website: www.bkacad.com 78 Lab 6.5.8 Học viện mạng Bách Khoa - Website: www.bkacad.com 79 Học viện mạng Bách Khoa - Website: www.bkacad.com 80 Testing the Network Layer Học viện mạng Bách Khoa - Website: www.bkacad.com 81 Testing the Local Stack • Pinging the Local Loopback: 127.0.0.1 6.6.1 Học viện mạng Bách Khoa - Website: www.bkacad.com 82 Testing Connectivity to the Local LAN • Ping Gateway 6.6.2 Học viện mạng Bách Khoa - Website: www.bkacad.com 83 Testing Connectivity to Remote LAN • Use ping to verify that a local host can communicate via a gateway to a device in remote network 6.6.3.1 Lab 6.6.3.2-Ping Học viện mạng Bách Khoa - Website: www.bkacad.com 84 Học viện mạng Bách Khoa - Website: www.bkacad.com 85 Testing the Path • Use tracert/traceroute command 6.6.4.1 Round Trip Time ? Lab 6.6.4.2- Trace Route Học viện mạng Bách Khoa - Website: www.bkacad.com 86 Học viện mạng Bách Khoa - Website: www.bkacad.com 87 ICMP v4 –The Protocol supporting Testing and Messaging • ICMP is the messaging protocol for the TCP/IP suite. ICMP provides control and error messages and is used by the ping and traceroute utilities. • ICMP messages that may be sent include: • Host confirmation • Unreachable Destination or Service • Time exceeded • Route redirection • Source quench • 6.6.5 Học viện mạng Bách Khoa - Website: www.bkacad.com 88 ICMPv4 • The purpose of these messages is to provide feedback about issues related to the processing of IP packets under certain conditions, not to make IP reliable. • ICMP messages are not required and are often not allowed for security reasons. Lab 6.7.1 – 6.7.5 Học viện mạng Bách Khoa - Website: www.bkacad.com 89 Q&A • Refer to the exhibit. Which network prefix will implement the IP addressing scheme for the LANs shown in the graphic? Học viện mạng Bách Khoa - Website: www.bkacad.com 90 Q&A • Refer to the exhibit. Host A is connected to the LAN, but it cannot get access to any resources on the Internet. The configuration of the host is shown in the exhibit. What could be the cause of the problem? Học viện mạng Bách Khoa - Website: www.bkacad.com 91 Q&A • The devices are recommended to be assigned static IP addresses: – servers –network printers – routers –Switchs – firewalls Học viện mạng Bách Khoa - Website: www.bkacad.com 92 Q&A • Which of the following are features of IPv6 –larger address space –data types and classes of service –authentication and encryption Học viện mạng Bách Khoa - Website: www.bkacad.com 93 Học viện mạng Bách Khoa - Website: www.bkacad.com 94 Summary Example • Major: 107.1.0.0/22 • Lan1,6: 200H • Lan2: 100H • Lan3: 90H • Lan4: 50H • Lan5:30H • Link: 2H Học viện mạng Bách Khoa - Website: www.bkacad.com 95 • 200H (/24) • 107.1.0.0 lan1 • 107.1.1.0 lan6 • 107.1.2.0 • 107.1.3.0 Học viện mạng Bách Khoa - Website: www.bkacad.com 96 • 100H, 90H • 107.1.2.0/24
/15 • .2.0 • 2.128 Học viện mạng Bách Khoa - Website: www.bkacad.com 97 • 50H • 107.1.3.0/24 -
/26 • .3.0 lan 4 • .3.64 • .3.128 • .3.192 Học viện mạng Bách Khoa - Website: www.bkacad.com 98 • 30H • .3.64/26
/27 • 3.64 Lan5 • .3.96 Học viện mạng Bách Khoa - Website: www.bkacad.com 99 • Link 2H • .3.96/27
/30 • .3.96 • .3.100 • Học viện mạng Bách Khoa - Website: www.bkacad.com 100 Học viện mạng Bách Khoa - Website: www.bkacad.com 101