Chapter 3 - Page 1 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting IP ADDRESSING & SUBNETTING

Chapter 3 - Page 2 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting TOPICS Numbering Systems What is IP Addressing? –The Hierarchical IP Addressing Scheme –Additional Classes of Networks –Who Assigns Network Addresses? Subnetting a Network –Implementing Subnetting –How to Implement Subnetting –Subnet Masks –Can This Be Make Easier?

Chapter 3 - Page 3 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting NUMBERING SYSTEMS Decimal – base 10 –Digits 0-9 –Example: 163 Binary – base 2 –Digits 0-1 –Example: Hexadecimal – base 16 –Digits 0-9, a-f –Example: a3

Chapter 3 - Page 4 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting DECIMAL NUMBERING SYSTEM Each position in a Decimal number represents a value Decimal digits – 0, 1, 2, 3, 4, 5, 6, 7, 8 and s3 - 1s

Chapter 3 - Page 5 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting BINARY NUMBERING SYSTEM Each position in a Binary Number represents a value Binary Digits – 1 and =

Chapter 3 - Page 6 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting CONVERT BINARY TO DECIMAL To Convert: –Identify the place holder value –Add all the values = 163

Chapter 3 - Page 7 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting CONVERT DECIMAL TO BINARY

Chapter 3 - Page 8 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting CONVERSION EXERCISES Convert the following decimal numbers to binary Convert the following binary numbers to decimal

Chapter 3 - Page 9 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting CONVERSION SHORTCUT CHART IP ADDRESSING SCHEME Addresses are fixed length of four octets (32-bits) –An address begins with a network number –An address ends with a local address (host/node number) There are three methods for depicting an IP address –Dotted-decimal – –Binary – –Hexadecimal – E 38 All of these examples represent the same IP address

Chapter 3 - Page 10 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting IP ADDRESS CLASSES Address Class Leading Bit Pattern 128 | 64 | 32 Decimal Range (1 st Octet) Address Template Number Of Networks Hosts Per Network 2^ Host Bits-2 A 01 – 126 B – 191 C CLASS A IP ADDRESS Class A: Net.Node.Node.Host The first bit of the first octet is always 0 Decimal range of first byte: Note: Network number 127 is reserved for diagnostics Maximum networks: 126 Maximum nodes per network: 16,777,216 0 Network IDHost ID

Chapter 3 - Page 11 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting CLASS B IP ADDRESS Class B: Net.Net.Node.Host The first two bits of the first octet are always 10 Decimal range of first byte: Maximum networks: 16,384 Maximum nodes per network: 65, Network IDHost ID CLASS C IP ADDRESS 110 Network ID Host ID Class C: Net.Net.Net.Host The first three bits of the first octet are always 110 Decimal range of first byte: Maximum networks: 2,097,152 Maximum nodes per network: 254 NOTE: Class D 224 – 239 – Used for multicast Class E 240 – 255 – Used for research purposes

Chapter 3 - Page 12 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting ADDRESSING GUIDELINES Network ID cannot be 127 –127 is reserved for loop-back diagnostics –Ping to test protocol installation Network ID cannot be all 1s or all 0s –All 1s indicates “Broadcast” –All 0s indicates “Any Address” Host IDs cannot be all 1s or all 0s –All 1s indicates “Network Broadcast” –All 0s indicates “The network only…” Private IP address (Private Internets) –Used for internal IP addressing –Will never be used on internet – – – – – – Class D Multicast –224 – 239 Class E Experimental or Scientific purposes –

Chapter 3 - Page 13 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting IP ADDRESSING EXERCISE IP AddressClassNetwork IDHost ID ETHERNET INTERFACE SETUP P2R1 P2R3P2R2 e0 s1s0 e0 s1 s0 e0 s1 s0 P1R1 P1R3P1R2 e0 s1s0 e0 s1 s0 e0 s1 s

Chapter 3 - Page 14 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting Divide a large network into smaller logical networks connected together by routers Uses bits from the host (node) portion of the address to create a subnet address Benefits of subnetting: –Reduced network traffic –Optimized network performance –Facilitate spanning of large geographical distances SUBNETTING A NETWORK

Chapter 3 - Page 15 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting SUBNET MASKS Distinguishes the network address from the host address –1’s represent the positions in the IP address that refer to the network or subnet address –0’s represent the positions in the IP address that refer to the host address –When coming from host end, remember to jump over one for subnet mask Network Mask Host Mask

Chapter 3 - Page 16 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting DEFAULT SUBNET MASKS Networks that have not been divided into subnets will use the default network mask for that class of address –Class A (binary) –Class B (binary) –Class C (binary) DEFAULT SUBNET MASKS # of Subnets = 2 N – 2 # of Hosts/subnetwork = 2 H – 2 N=number of bits used for subnetting H = number of bits used for the host address

Chapter 3 - Page 17 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting CUSTOM SUBNET MASKS Maximum number of subnets 2 (number of masked bits) – 22 4 = (16) – 2 = 14 Maximum number of hosts 2 (number of unmasked bits) –22 12 (4096) – 2 = Network Mask Host Mask Subnet Mask

Chapter 3 - Page 18 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting HOW TO IMPLEMENT SUBNETTING An IP address can be given a subnet address by reducing the number bits designated as the host portion of the address Network Mask Host Mask Subnet Mask Subnet Mask Subnet Address Network Address Host Address Class B Network Address HOW TO IMPLEMENT SUBNETTING Determine the number of required Network Ids –One for each subnet –One for each Wide Area Network connection

Chapter 3 - Page 19 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting NETWORK ADDRESSING Determine the number of required host Ids per subnet –One for each TCP/IP host –One for each router interface NETWORK ADDRESSING One subnet mask for your entire network A unique subnet ID for each physical segment A range of host IDs for each subnet Subnet A Host Subnet C Subnet B Network Subnet Mask

Chapter 3 - Page 20 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting IMPLEMENTING SUBNETTING The subnet mask will determine how many bits are used to create new subnetworks and how many bits are available for use as Host Ids Requirements Analysis –Determine number of subnets required –Determine number of hosts on largest subnet Compute Subnet Mask Determine Subnet Ranges Determine Assignable Host Addresses Subnet A Host Subnet C Subnet B Network Subnet Mask Host SUBNET PROCEDURES

Chapter 3 - Page 21 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting SUBNET REQUIREMENTS ANALYSIS How many subnets are required? How many hosts per subnet? 14 PC’s 12 PC’s 10 VAC’s 2 Main-frames Add 2 subnet and host fields. These are for the reserved addresses (all 0s and all 1s) –5 + 2 = 7 Subnet – = 17 Hosts Round Subnet and Host up to next power of 2 – –Subnets = 7 rounded up to 2 3 (8) –2 = 6 subnets –Hosts = 23 rounded up to 2 5 (32) – 2 = 30 Subnets COMPUTE SUBNET MASKS

Chapter 3 - Page 22 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting COMPUTE SUBNET MASK 2 3 – the 3 represents the number subnet bits which are masked and are indicated with 1’s 2 5 – the 5 represents the number of host bits which are not masked and are indicated with 0’s The appropriate Subnet Mask is: = Net IDHost ID DETERMINE SUBNETS Determine the range of available subnets

Chapter 3 - Page 23 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting SUBNET EXAMPLE – CLASS C Valid hosts in subnet Mask =

Chapter 3 - Page 24 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting SUBNET REQUIREMENTS ANALYSIS 58 PC’s, 2 Servers 34 PC’s, 1 Server How many subnets are required? How many hosts per subnet?

Chapter 3 - Page 25 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting SUBNET PROCEDURES Requirements Analysis –Determine number of subnets required: ______________ –Determine number of hosts on largest subnet: ______________ Compute Subnet Mask: ________________________ –Subnet multiple: ______________ –Hosts/subnet: _______________ Subnet Net IDs Host Address Range _______________ ___________________________ SUBNETTING A NETWORK ADDRESS P2R1 P2R3P2R2 e0 s1s0 e0 s1 s0 e0 s1 s0 P1R1 P1R3P1R2 e0 s1s0 e0 s1 s0 e0 s1 s0 Assigned by Pod 2 Assigned by Pod

Chapter 3 - Page 26 Infogem Institute of Technology CCNA Course IP Addressing & Subnetting Lab – Page 158 Review Questions Page 160 Homework: - Written Lab - Review3-10 & 13-20