IP Networking Part 3- IP Address Management A webinar to help you prepare for the CBNE Certification

Transcription

1 IP Networking Part 3- IP Address Management A webinar to help you prepare for the CBNE Certification Wayne M. Pecena, CPBE, CBNE Texas A&M Information Technology Educational Broadcast Services

2 IP Networking, Part 3 - IP Address Management A webinar to help you prepare for the CBNE Certification Advertised Presentation Scope: IP Networking Fundamentals for Broadcast Engineers is an intensive instructorlead workshop focused on major IP networking topics. The goal is to equip the broadcast engineer with the knowledge and understanding of IP networking fundamentals and the ability to apply conceptual theory in a practical manner. The workshop will focus upon the principals of IP Addressing and application of best practices in the design of an IP network address plan. My Goals & Deliverables for This Afternoon: - Provide an Awareness of Major IP Networking Topics (broadcast application focused) - Provide an Understanding of IP Addressing Fundamentals - Provide a Foundation for SBE CBNT & CBNE Certification Exams - Provide Reference Material & Resources to Obtain Further Knowledge 2

3 A Poll? My Familiarity & Conformability with IP Addressing is: Not at All Somewhat Familiar, But I Struggle At Times Very Comfortable, I Am Here for the Free Lunch 3

4 IP Networking, Part 3 - IP Address Management A webinar to help you prepare for the CBNE Certification IP Address Basics (IPv4) IP Addressing Rules IP Address Classes IP Subnetting Fundamentals The IPv6 Address Practical Exercises: Reverse Engineering an IP Address Plan Developing an IP Addressing Plan 4

5 REVIEW - Physical & Virtual Addressing Each Host on an Ethernet Based IP Network Has: An Unique MAC Address Layer 2 Physical Address (local network segment) An Unique IP Address Layer 3 Logical Address (global routed) Simplified Representation FF:FF:FF:FF:FF:FF 00:12:3F:8D:4D:A DATA Trailer Destination MAC Source MAC Source IP Destination IP IP Packet Ethernet Frame 5

6 The IP Address: Is a Logical Address OSI Model Layer 3 Function Allows Hierarchical Network Addressing Structure Creates Boundaries Between Networks Allows Routing Packets Between Networks Must Have a Subnet Mask: Implied Explicit Address & Mask Defines: Unique Network ID Unique Host ID 6

7 The IP Address (IPv4) 32 Bit Address Yields 4,294,967,296 IPv4 Addresses Expressed in Decimal as (4) 8-bit Octets using Doted Decimal Notation

8 The IP Address Subnet Mask Each IP Address Must Have a Subnet Mask 32 Bit Subnet Mask Expressed in Decimal as (4) 8-bit Octets using Doted Decimal Notation

9 Purpose of the Subnet Mask Identifies the Network Portion and the Host Portion of the IP Address Classful Addressing Mask is Implied Based Upon Class Classless Addressing Mask Must Be Specified Octet 1 Octet 2 Octet 3 Octet 4 Class A NET ID HOST ID 8 Bits 24 Bits Class B NET ID 16 Bits HOST ID 16 Bits Class C NET ID 24 Bits HOST ID 8 Bits 9

10 Rules: The Subnet Mask: If Mask Bit =1 Identifies the Network If Mask Bit=0 Identifies the Host Address Mask Network Host Class Octet 1 Octet 2 Octet 3 Octet 4 A Network Host Host Host B Network Network Host Host C Network Network Network Host 10

11 IP Address Classes Used to Set Different Network Sizes The 1 st Octet of an IP Address Determines It s Class: Class First Octet Subnet Mask (implied) CIDR Maximum # of Networks # Host Bits # of Hosts / Network A / ,777,214 B /16 16, ,534 C /24 2,097, The 1 st Octet of an IP Address Dictates the Class 11

12 The 1 st Octet of an IP Address Determines It s Class: If First Bit = 0 Class A If First 2 Bits = 10 Class B If First 3 Bits 110 Class C If First 4 Bits = 1110 Class D If First 4 Bits = 1111 Class E Recognize Class D & E Are Special : Class D Reserved for Multicast Class E Reserved for Experimental 12

13 A Quiz! What Class Are the Following IP Addresses? Class A Class B Class C Class D Class A Class B Class C Class E Class A Class B Class C Class D 13

14 The Network & Broadcast Addresses These Addresses Cannot Be Assigned to a Host! Network (subnet) Address ALL HOST BITS = 0 Broadcast Address ALL HOST BITS = Network Example: /24 Broadcast Example: /

15 Private vs Public IP Addresses RFC 1918 Established Private Address Space Class A: to /8 Class B: to /16 Class C: to /24 Key Points: Private IP Addresses Are NOT Routable Outside the Local Network or to the Internet Widely Used in Home & Industry Networks May Be Translated With NAT At An Edge Router Map Private Address Space to Public Address Space 15

16 CIDR RFC 1517, 1518, 1519, 1520 Classless Inter-Domain Routing (CIDR) Simplified Approach to Stating the Subnet Mask / Notation (slanted notation) Utilized = # Bits That Are 1 Mask: Expressed in Binary: Bits Mask (CIDR): /28 16

17 IP Address & Subnet Mask Formats Classful Addressing: (Implied Mask ) VLSM Addressing: CIDR Notation : /26 Implied Mask Of a Class B Network Explicit Mask Must Be Stated Mask Stated as Number of Subnet Bits 17

18 Special Use IP Addresses RFC /8 Network Address Wire Address /8 Private IP Address Space (RFC 1918) /8 Loopback Address /16 IETF Zero Configuration Address Space (RFC 3927) /16 Private IP Address Space (RFC 1918) /16 Private IP Address Space (RFC 1918) /4 Multicast Address Space /32 Broadcast Address And more special use cases..yields a little over 3.7m Useable IPv4 Addresses (3,706,650,624 out of 4,294,967,296 possible IPv4 addresses or 86%) 18

19 What is Special About ? IP Address Trivia Actually Any /8 Address Works OR the Range of to Known as a Loop-Back Address Useful For: Test Local IP Stack and Network Adapter Test 19

20 IP Address Subnetting What is a Subnet? Logical Subdivision of a Larger Network Creates New Networks From A Larger Network Bits Are Stolen From the Host Portion Each Newer Network Created Has Less Hosts 2 n -2 New Networks Created where n=number of host bits stolen Why Do We Subnet? Efficient Use of IP Address Space ( Right Size the Network) Increase Performance (smaller Broadcast domain) Enhance Routing Efficiency (reduce Routing Table size) Network Management Policy and Segmentation (function, ownership, geo location) Job Security for Network Engineers! 20

21 Subnetting Simply Moves the Boundary between the Network and Host Moves Boundary to the Right Boundary Position Determined by the Subnet Netmask Provided IP Address Space: /16 Represents 4,096 IP Addresses Or 256 /24 Class C Blocks Provided IP Address Space: /16 Represents 4,096 IP Addresses / / / / / / / /23 C D 12 5 A / /22 B / /24 21

22 Subnetting Basics Identifies the Boundary Between Network and Hosts Subnetting Simply Moves the Boundary! Moves Boundary to the Right IP Address Subnetting Applies to All Classes Boundary Position Determined by the Subnet Netmask Expressed in Several Forms: Doted Decimal Notation (same as IP address) Slash Notation (also known as CIDR notation) IP Address with Netmask of OR /24 22

23 Required Host IP Configuration Information IP Address Address Mask Gateway Address DNS Server Address(s) Where Do We Get This Information? 23

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25 Network Questions to Answer How Many Subnets Are Available? How May Hosts per Subnet Are Available? What Are the Subnets? What is the Broadcast Address of Each Subnet? What Are the Valid Hosts in Each Subnet? 25

26 What Must Be Known About a Network? IP Address and Mask Provides: First Network Address First Network Address Assignable to a Host Last Network Address Assignable to a Host Broadcast Address /24 Provides: 254 useable IP addresses Mask: Network Address (Wire Address) First Network Address Assignable to a Host Last Network Address Assignable to a Host Broadcast Address

27 Subnet Calculation Examples /20 Provides: 4094 useable IP addresses Mask: Network Address (Wire Address) First Network Address Assignable to a Host Last Network Address Assignable to a Host Broadcast Address /28 Provides: 14 useable IP addresses Mask: Network Address (Wire Address) First Network Address Assignable to a Host Last Network Address Assignable to a Host Broadcast Address

28 An Exercise? Is mask a Valid Host IP Address? Yes No It Depends 28

29 Lets See! mask Convert Mask to Binary : Convert Mask to Inverse Mask: subtract from all 1's AND IP Address & Mask: Yields the Network Address: OR Inverse Mask to Network Address: Yields the Broadcast Address: Thus: Network: st Host: Last Host: Broadcast: The Answer Is NO is Not a Valid Host Address (It s the Broadcast Address) 29

30 IPv6 Address Space IETF - RFC 2460 IPv6 Provides Expanded IP Address Space = 340,282,366,920,938,463,463,374,607,431,768,211,456 (three hundred forty UNDECILLION addresses) 3.4 x But, IPv6 is More Than Expanded Address Space: An Opportunity to Re-Engineer IPv4 Improved Support for Multicasting, Security, & Mobile Aps Multiple Addresses per Interface Host Auto-Configuration Capability Security Incorporated MTU Discovery Incorporated Traffic Engineering Provisions Incorporate

31 The IPv6 Address 128-Bit Address Binary Format: Subdivide Into Eight (8) 16-bit Groups: Convert Each 16-bit Group to Hexadecimal: (separate with a colon) 2607:b800:0faa:0003:2195:9887:bc48:28f1 2607:b800:faa:3:2195:9887:bc48:28f1

32 Address Summarization 128-Bit Address Represented as a 32 Hexadecimal Digits Subdivided Into Eight Groups (Chunks, Quads, Quartets) of Four Hexadecimal Digits (separated by colon) 2001:0000:0000:0000:0DB8:8000:200C:417A or 2001:0:0:0:DB8:8000:200C:417A or 2001::DB8:8000:200C:417A

33 Address Summarization 128-Bit Address Represented as a 32 Hexadecimal Digits Subdivided Into Eight Groups (Chunks, Quads, Quartets) of Four Hexadecimal Digits (separated by colon) 2001:0000:0000:0000:0DB8:8000:200C:417A or 2001:0:0:0:DB8:8000:200C:417A or 2001::DB8:8000:200C:417A 33 33

34 An Ipv6 Address You Can Remember The IPv6 Loopback Address ::1 Summarized from: 0:0:0:0:0:0:0:1

35 IP Addressing Reverse Engineering A Useful Troubleshooting Tool Verifying Proper Subnet Configuration When Given an IP Address and Subnet Mask Determine Subnet Address Range Determine Assignable IP Addresses Determine Broadcast Address Subnetting When Given A Network Requirement Subnetting When Given A Host Requirement You Are Provided: IP Address / IP Mask 35

36 IP Address Subnetting Charts 36

37 Subnet Calculation Tools 37

38 Hints for Subnetting VLSM Mask Block Size /25 /27 /28 /29 /30 /31 /32 CIDR /26 4 th Octect Remember George Boole AND OR

39 Practical Exercise Reverse Engineering an IP Address Plan Refer to Exercise Handout 39

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41 Practical Exercise #2 Developing an IP Addressing Plan Refer to Exercise Handout 41

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43 Subnet Number: Subnet Mask: First IP Address: Broadcast IP Address: Last IP Address: Subnet Number: Subnet Mask: First IP Address: Broadcast IP Address: Last IP Address: Subnet Number: Subnet Mask: First IP Address: Broadcast IP Address: Last IP Address: What additional IP configuration information is required to configure hosts on this network? Default Gateway 43

44 The Calculator Approach! 44

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46 Web Reference Sources: Subnet Calculation Tools: ios App $: calculator/id ?mt=8 RFC Documents: IP Address Subnet Block Size Chart: 46

47 Web Reference Sources continued. IP Subnetting Cisco Networkers Magic Box Tutorial: Cisco IP Subnetting Game: 47

48 CBNE Recommended Study: 48

49 My Favorites: 49

50 ? Questions? Thank You for Attending! Wayne M. Pecena Texas A&M University