Automatic Private IP Addressing (APIPA) is a feature of Windows-based operating systems (included in Windows 98, ME, 2000, and XP) that enables a computer to automatically assign itself an IP address when there is no Dynamic Host Configuration Protocol (DHCP) server available to perform that function. APIPA serves as a DHCP server failover mechanism and makes it easier to configure and support small local area networks (LANs).
RARP help the PC to find its MAC address in the same network from the RARP Server.RARP Serveronly providethe IP adress to the PC by remembering its MAC.DHCP works on the same way but DHCP Server provide the PC its IP address, Subnetmask, Default Gateway and DNS Server etc...So the big difference is DHCP provide more information than your RARP Server.
DHCP s just a server that provides IP details to a computer. Since it can be set up to give statc IP address details to specific computers it has no disadvantage....unless of course the DHCP server crashes.
Dhcp is Direct host configure protocol. This is used to assign IP address Automatically. In a Domain Environment we must need IP Addresses to communicate with one machine to another to access the resources, their are mainly two ways to configure a IP in a system One is static or manual IP and other is Dynamic or Automatic IP. So DHCP help us to configure an IP Address Dynamically.(Network+ Guide to Networking answer)BOOTP relies on a static table to associate IP addresses with MAC addresses, whereas DHCP does not
This means that the device will no longer be a "router" ... it will simply pass through IP addresses in the same subnet as the one it is given (presumably by an upstream router). This is useful for networks where there is an existing router (e.g., uverse gateway) with built-in wireless, but you want to locate the wireless access point in a different location from the router. Note that a router would typically have an IP address in one subnet (provided by the WAN or an upstream router) and it would provide IP addresses using DHCP typically in another subnet. So your cable modem is a router in that it gets an external IP from the cable company. But then it provides 192.168.x.x addresses to you. If you add an additional router it might be given a 192.168.x.x address and then provide 10.1.1.x addresses to you. If the additional "router" above were in "AP mode" then it would have a 192.168.x.x address and it would pass through DHCP requests to the cable modem... so everybody would get a 192.168.x.x address.
An APIPA stands for, Automatic Private IP Address. Basically the majority of people use DHCP to obtain there IP address and configurations. For this to work, a DHCP server must be running. DHCP servers are found in home routers, gateways, modems, or corporate servers. However, If there is no DHCP server that is reachable, you will get an APIPA. APIPA is a range of IP address just for Microsoft operating systems. An APIPA ranges from 169.254.0.1 through 169.254.255.254. When it is activated, it constantly looks for a DHCP server to get a configuration from. When it finds a proper configuration, APIPA is disabled.
APIPA (Automatic Private IP Addressing) is a feature in Windows operating systems that allows devices to automatically assign themselves a private IP address in the absence of a DHCP server. When a device with APIPA enabled cannot find a DHCP server to assign it an IP address, it will assign itself an IP address in the range of 169.254.0.1 to 169.254.255.254. This ensures that the device can still communicate on the local network, even without a DHCP server.
FalseEven if your network does not need or use APIPA, leaving it enabled is not necessarily problematic, because APIPA is designed to first check for the presence of a DHCP server and allow the DHCP server to assign addresses. In addition if a computers IP address has been assigned statically, APIPA does not reassign a new address. It only works with clients configured to use DHCP. APIPA can be disabled ,However, by editing the Windows operating system registry.
Short for Automatic Private IPAddressing, a feature of later Windows operating systems. With APIPA, DHCP clients can automatically self-configure an IP address and subnet mask when a DHCP server isn't available. When a DHCP client boots up, it first looks for a DHCP server in order to obtain an IP address and subnet mask. If the client is unable to find the information, it uses APIPA to automatically configure itself with an IP address from a range that has been reserved especially for Microsoft. The IP address range is 169.254.0.1 through 169.254.255.254. The client also configures itself with a default class B subnet mask of 255.255.0.0. A client uses the self-configured IP address until a DHCP server becomes available.The APIPA service also checks regularly for the presence of a DHCP server (every five minutes, according to Microsoft). If it detects a DHCP server on the network, APIPA stops, and the DHCP server replaces the APIPA networking addresses with dynamically assigned addresses.APIPA is meant for nonrouted small business environments, usually less than 25 clients.
Automatic Private IP Address was basically made so that clients which could not get an IP address automatically from a DHCP server could configure its own Private IP address until it can obtain address from the DHCP server which will override the APIPA and become the new IP address.
It's called APIPA (automatic private ip addressing).
APIPA avoids the problem of IP hosts being unable to communicate if a DHCP server is unavailable,which stands for Automatic Private IP Addressing. APIPA is a Windows feature that allows a computer to determine IP configuration information without DHCP. It is only useful on a small workgroup and not a large network.
According to Microsoft:How to use automatic TCP/IP addressing without a DHCP server"A Windows-based computer that is configured to use DHCP can automatically assign itself an Internet Protocol (IP) address if a DHCP server is not available. For example, this could occur on a network without a DHCP server, or on a network if a DHCP server is temporarily down for maintenance."For more information, see Related Links, below.
APIPA, also known as Automatic Private IP Addressing, is a feature used in Windows operating systems. It comes into action only when DHCP (Dynamic Host Configuration Protocol) servers are available. When the DHCP client first comes on, it will try to establish a connection with the DHCP server in order to get an IP address. It is when this server is (or at a later point becomes) unavailable, that APIPA will kick in.As the client is unable to connect with the server, APIPA will automatically try to configure itself with an IP address from an specially reserved range. (This reserved IP address range goes from 169.254.0.0 to 169.254.255.255).After an IP address is obtained using APIPA, the client will then verify that their IP address is a unique one on the LAN. This is done utilizing ARP. According to Microsoft guidelines, APIPA will also check regularly to see whether the DHCP servers are available. If at any point it does become available, then the APIPA service will discontinue itself de-allocating the IP address it has obtained, and allow the DHCP server to allocate a dynamic IP address.When APIPA takes over and your client has been assigned an IP address, the client will be able to communicate with other computers also on that LAN which have also been configured by APIPA, or failing that, which have been assigned a static IP address in the range mentioned earlier (so and IP address like 169.254.x.x, where ".x.x" are the identifiers unique to that particular computer).However, if you are connected to the internet without a NAT, or even a proxy server, or you use routers, you might want to turn the APIPA feature off. For more information on this you can go to straight to the source at Microsoft's Help and Support pages on "How to use automatic TCP/IP addressing without a DHCP server" at this address http://support.microsoft.com/kb/q220874/All the information you need to on how to turn APIPA off, is contained here.In essence the APIPA service is a fail-safe device put in place by Microsoft to make sure that everything runs smoothly. There is nothing that you need to do about it as it all happens in the background, and at speeds and times of which you are unaware of. In fact, by the time you detect that your DHCP server is unavailable, and you try to rectify the matter, APIPA would have already taken the proper steps necessary to keep your client running smoothly.
169.254.10.1 is an IP address generated automatically by a computer when it is unable to lease an address from a DHCP server. It is called an Automatic Private IP Addressing (APIPA) address.
DHCP Server can be a standalone server
Cause of getting APIpa(169.254.x.x) is failure of DHCP server to get IP address or might be DNS service failure . This could be because of possible outage from ISP . use command "netsh winsock reset catalog" and restart computer . it will refresh the DHCP stack of IP for local host and might fix problem if the issue is from user machine .