IP Addressing

1

• IP Addressing

Lecture 1 Hassan Shuja 01/31/2006
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IP Addressing

• What is it
• An IP address is an address used to uniquely
  identify a device on an IP network
• An address is a 32-bit numeric address written as
  four numbers separated by periods
• IPv4 is made up of 5 different classes
• Class A,B,C,D,E
• Class A,B,C are standard Internet and intranet
  routable addresses
• Private addresses are only intranet routable
• Class D are Multicast addresses and class E are
  used for research

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IP Addressing

• What is it
• IP addresses are used by routers to route packets
  to destinations

4
IP Addressing

• What is it
• An address is made up of a network portion and a
  host portion
• The network portion is used to identify the
  network
• Does not change within a network or subnetwork
• The host portion is the range of addresses
  assigned to nodes on the network
• Standard Network Host portion of Class A,B,C
• Class A n h.h.h
• Class B n.n h.h
• Class C n.n.n h

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IP Addressing

• Obtaining IP Addresses
• IANA is the governing body for all IP addresses
  and has regional registry organizations
• American Registry for Internet Numbers (ARIN)
  supports North America region
• IANA requires justification before they allocate
  a range of IP addresses for somebody
• Most IP addresses these days are obtained through
  ISPs

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IP Addressing

• Subnet Mask
• A 32-bit value that is used to distinguish the
  network ID portion of the IP address from the
  host ID
• Subnet Masks determines size of local subnet
• Helps determine if two addresses are on the same
  network
• Default Gateway
• Default Gateway handles requests that are
  destined for outside of the local subnet
• The address of the router on the local subnet

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IP Addressing

• Subnetting
• A Method use to break up large networks into
  smaller ones
• Splits the host field into a subnet and host
  section
• This splitting is determined by the subnet mask
• The Network field remains unchanged
• Subnetting allows for ease of administration,
  conservation of IP addresses, limit broadcast
  domains, and efficient use of resources
• Converting Decimal to Binary
• http//www.cuyamaca.net/curtis.sharon/pdf/CiscoLab
  s/lab_1_2_5.pdf