What is an IP helper?
As we all know IP stands for Internet Protocol. It helps a local computer for network administration. This is done as follows: the information about the local computer’s network configuration can be accessed by enabling the local computer’s applications. Also, it can modify the local computer’s network configuration. While changing this local computer’s network configuration, it must ensure that the application is notified by that modification. The IP helper provides many mechanisms for this.
Most of the functions of IP helper can be used to transmit the structure parameters. These parameters contain the data types regarding the technology, Management Information base. Also to show the different kinds of networking information( ARP cache entries are the example for such networking information ) these structures are used by the IP helper. The MBI API also uses these structures. The Management Information Base Reference describes this. IP helper is different from both Simple Network Management Protocol and the above one because these structures are used by the IP helper.
We can see the terms interface and adapter while the documentation of IP helper. The adapter actually represents a kind of network hardware. It is actually the short form of the network adapter. it is a datalink-level abstraction. Where the IETF RFC documents are used by the first term, interface. In the concept of an RFCs, the interface is the attachment from the node to the link. Its abstraction level is IP-level.
There is a number of adapters and interfaces are used in the documentation of an IP header( look back interface and software WAN interfaces are examples for such interface which are not a hardware device ). The relation between the adapter and the interfaces are one-to-one mapping in IP helper APIs.
IP helpers can be used for the following purposes:
- Accessing local computer network configuration information.
- Modifying local computer network configuration information.
- Network adapter management.
- IP address management.
- Routing can be managed by IP headers.
- It can be used to access the information from the Internet Protocol as well as from the Internet Control Message Protocol.
- It will receive a notification if any events occurred there.
- Details about the User Datagram Protocols and Transmission control protocol can be accessed by the IP header.
- It uses the protocol named Address Resolution Protocol.
We can set up a DHCP relay by using the following command:
Since DHCP uses a broadcast network, it only works on the LAN where it is connected. The DHCP rely on was created for solving a problem that DHCP cant cross a router. So, now the router can be intercepted by the request of a client and it results in making a unicast request to the server of DHCP that is situated in another LAN. And then the sever on that LAN can be responded to the router back in a unicast way and at last, the final response is passed to the client which initiated the request.