Why IP address (IP Address Picture Book-1 from VisualLand Animations)

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Why IP addressIP Address Picture Book
1www.visualland.net

• Watch animation to learn networking.
• Shows how IP addresses are being used when
  computers are transmitting messages. Each packet
  is tagged by sender and receiver's IP addresses.
• This picture tutorial takes screenshots from IP
  Address Animation.
• OK to republish this slide. Please use hyperlink
  to point to its source.

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IP Address animations

• Why IP address? Visualize how IP addresses are
  being used when Internet forwards messages
  between computers.
• 2. How Internet Forwards Packets? Computers
  are connected to Internet via gateway routers.
  Routers use routing table to make packet
  forwarding decisions.
• 3. Network Address. A 32-bit IP address is
  divided into network ID (left bits) and host ID
  (right bits). Router uses network addresses to
  forwad packets.
• 4. Classful IP Address. Present IP addresses
  in A, B, C, D classes by byte boundary with
  a.4-digit form (a.b.c.d) and show how routing
  table does lookup.
• 5. Subnettiing - Classless IP address It uses
  a class B address and its 5 subnets as an
  examples to show how routing table lookup works
  with different network mask.
• 6. VLSM Show a good subnetting design case
  that aggregatrd routes in a routing table. Ans
  show a bad case that cannot aggregate routes.

2019/1/29
www.visualland.net
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Overview Why IP address? Animation Link
Goal Use Ping to show how computers are using IP
addresses to send and receive messages across
Internet. Topology 3 computrers are connected to
Internet. Each is assigned an individual IP
address. Steps 1) Jack ping Rose. It transmits
a Ping packet with "Receiver address" to be
Rose's IP address, 2) Internet
forwards Ping to Rose. 3) Rose
receives Ping and sends an Echo back to Jack.
Internet forward Echo to Jack.
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Topology?IP Addresses

• In this case study, we present a simplied
  Internet. Three computers Jack. Rose, and Mary
  are connected to
• Internet, Their IP addresses are100.4.5.6,
  150.1.2.3, and 222.111.44.33. This topology will
  be reused in the
• following IP Address simulations.
• Note See FAQ for more information on IP
  addresses usage and structure.

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Jack Ping Rose
Jack wants to know whether Rose is online. He
ping Rose. A Ping packet is transmitted from
Jack's computer. This packet carries two
addresses like a postal mail. Receiver address is
Roses' IP address 150.1.2.3. Sender address is
Jack's IP address 100.4.5.6. Jack has no idea
where Rose is located. He is counting on Internet
to delver it to Rose. Click Ping to see its
addresses.
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Internet forwards ping
When Internet receives Ping packet, it sees the
receiver's address is 150.1.2.3 and forwards Ping
to Rose. We can look at the Internet as a big
communication black box. You pass a message to it
with a receiver's IP address and Internet will
deliver it for you. The only thing Internet needs
is the correct receiver IP address.
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Rose sends an Echo to Jack
When Internet receives Ping packet, it sees the
receiver's address is 150.1.2.3 and forwards Ping
to Rose. We can look at the Internet as a big
communication black box. You pass a message to it
with a receiver's IP address and Internet will
deliver it for you. The only thing Internet needs
is the correct receiver IP address.
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Rose sends an Echo to Jack
When Internet receives Ping packet, it sees the
receiver's address is 150.1.2.3 and forwards Ping
to Rose. We can look at the Internet as a big
communication black box. You pass a message to it
with a receiver's IP address and Internet will
deliver it for you. The only thing Internet needs
is the correct receiver IP address.
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Rose sends an Echo to Jack
When Internet receives Ping packet, it sees the
receiver's address is 150.1.2.3 and forwards Ping
to Rose. We can look at the Internet as a big
communication black box. You pass a message to it
with a receiver's IP address and Internet will
deliver it for you. The only thing Internet needs
is the correct receiver IP address.
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FAQ

• Why do we need IP address?
• What is the structure of IP address?
• How many IP addresses are there?
• What is Internet?
• How does Internet deliver computer messages?
• ( answers in the Comments box )

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What is Vlabvisualland.net

• VLAB Virtual Lab
• Theory Visualize key points of network protocols
  to help beginners grasp the basic ideas quickly.
• Lab Visualize network activities with packets
  and router states captured from network
  simulators (dynamips, packet tracer, and ns2.
• Interactively control animation packet headers,
  protocol state tables.
• Vlab usage
• Self learning, teaching aids, lab book.