The document discusses Automatic Private Internet Protocol Address (APIPA), which enables devices to self-configure with a private IP address in the 169.254.0.0/16 range when a DHCP server is unavailable. It explains that APIPA is enabled by default in Windows and can be disabled by editing the registry, and outlines how APIPA works to allow devices to communicate on a local area network when DHCP fails. The disadvantages of APIPA are that addresses are only for local use and it does not provide a network gateway address.

1. Presented By
KRITIKA CHAUHAN

2.  What is APIPA?
 What is Private Address?
 What is the range of APIPA?
 When and Why APIPA?
 How APIPA works?
 When APIPA enables & how to disable APIPA?
 Disadvantages of APIPA.

3.  APIPA stands for Automatic Private Internet
Protocol Address.
 APIPA is a feature of windows based OS that
enables a device to automatically self-
configure with a Private IP address.

4.  APIPA stands for Automatic Private Internet
Protocol Address.
 APIPA is a feature of windows based OS that
enables a device to automatically self-
configure with a Private IP address.
A private IP address is one which is assigned to each device to
communicate with other devices in a LAN.

5.  APIPA uses a Class B IP address that ranges
from 169.0.0.0 - 169.255.255.254 with
subnet mask of Class B i.e 255.255.0.0
 IANA has reserved this range for APIPA.

6.  APIPA is used to assign IP address to those
devices who wants to communicate with
other one’s in a LAN, when DHCP is
unreachable.
 APIPA overcomes the DHCP server failure.

7.  Device who wants to communicate sends a
discover message to DHCP.
 If DHCP fails then the device self-configured
with an IP address.
 ARP is used to check address conflict occurs
or not.
 Simultaneously, the client lookup for DHCP.
 If DHCP is available, then it update the
addresses automatically by replacing the
present one.

8. DHCP
Server
SWITCH
PC1
PC2

9. DHCP
Server
SWITCH
PC1
PC2
PC3

10. Discover
DHCP
Server
SWITCH
PC1
PC2
PC3

11. Unavailable
Discover
DHCP
Server
SWITCH
PC1
PC2
PC3

12. Unavailable
Discover ARP msg
Self-Configured
DHCP
Server
SWITCH
PC1
PC2
PC3

13. Unavailable
Discover ARP msg
Self-Configured
DHCP
Server
SWITCH
PC1
PC2
PC3

14. Unavailable
Discover ARP msg
Self-Configured
DHCP
Server
SWITCH
PC1
PC2
PC3

15. Unavailable
Discover
Self-Configured
DHCP
Server
SWITCH
PC1
PC2
PC3

16. Available
Discover
Self-Configured
DHCP
Server
SWITCH
PC1
PC2
PC3

17. Available
Provide IP
Self-Configured
DHCP
Server
SWITCH
PC1
PC2
PC3

18. Available
Provide IP
Accept new IP &
Replace the old one
DHCP
Server
SWITCH
PC1
PC2
PC3

19.  APIPA is enabled by default in windows
whenever the device network interface is
configured for DHCP.
 APIPA can be disabled by editing the window
registry setting value to 0.
 For disabling it, type ctrl+R and write
“regedit”.
HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services/TcpipParamete
rs/IPAutoconfigurationEnabled

20. If you want to know that your device is
configured with APIPA or DHCP then type
“ipconfig /all” in cmd and then press ENTER.

21. If you want to know that your device is
configured with APIPA or DHCP then type
“ipconfig /all” in cmd and then press ENTER.
Displays all current TCP/IP network
configuration value

24.  APIPA addresses are restricted for use on
local networks only.
 APIPA does not provide the network gateway
address as DHCP does.
 APIPA configured devices follows peer to peer
communication rule.

25. Any Query