DNS, DHCP, IPAM – together they form what we often call DDI. They all work together to manage, assign and resolve IP addresses and form an important part of any network.Read on as we explain what each of these components are, what they are used for, and why you need them.
Today we’ll start our journey by discussing IP addresses, what they are and why we use them Guest wifi solutions . Then we will introduce the DHCP system, how it works and what are its various components. After that, we will discuss the interaction between DNS and DHCP and why it is so important. And we’ll end this crash course by explaining what DDI is and why it’s so important Wifi6 wireless solutions.
IP addresses are at the very center of the Internet. They uniquely identify each device connected to the network. An important distinction needs to be made between public IP addresses and private IP addresses. The first are those used on devices connected to the public Internet. For example, a web server often has a public IP address. Outdoor wifi solutions The Internet router installed by your ISP in your home also has a public IP address. On the other hand, private IP addresses are the ones we use on home and corporate networks. They must also be unique, but only within a specific network.
Back in the history of the Internet, when the IP protocol was defined, each connected device was manually configured with a separate IP address. We called it static or fixed IP addressing. This was cumbersome but ok as the number of connected hosts was low. As networks (both public and private) grew, it became more difficult to manually configure IP addresses as the process was error prone and often resulted in duplicate IP addresses on the network. It took until the early 1990s before a durable solution was introduced in the form of DHCP. Wifi solution
The Dynamic Host Configuration Protocol – or DHCP as we commonly call it – was invented to dynamically assign IP addresses and provide connectivity to connected hosts.DHCP eliminates the need to manually configure IP addresses. Hotel wifi solution DHCP not only configures IP addresses, it can configure most of the network parameters of the connected host, such as IP address, subnet mask, name servers, WIND server (s) in Windows environment, and a few other parameters. All parameters are dynamically configured every time the host is started on the network.
How it works
No matter what the exact parameters are configured by DHCP, the process for configuring a host is always the same. This is a four-step process called DORA, which stands for Discovery, Request, Offer, and Acknowledgment. Guest-wifi solutions This is what happens when the host starts.
During the discovery phase, the host sends out a broadcast message – this is a message that will be accepted by any host connected to the network called DHCPDISCOVERY. The message must be forwarded because the host does not know the DHCP server address at this time.
In the second step, the server responds with a DHCP offer. The offer contains all the configuration parameters for the host’s network interface. Now, this is where things get a little tricky. Since there can be multiple DHCP servers on the network, a host can receive multiple offers. When this happens, the host will simply pick one of the suggestions and move on to the next step. Which one should you choose? Usually he chooses the first offer he receives.
In the next step, the host sends a DHCP request. It includes the offer that he chooses and will instruct the server whose offer he chose to continue, informing other servers that sent offers that they had rejected and that they can release the offered IP addresses Cloud managed wifi solutions .
In the final step, the server sends a DHCP acknowledgment to the host, confirming that it has correctly reserved the proposed IP address for that host.
DHCP client component
DHCP configuration information obtained by the client and used to configure the network interface is not valid forever. In fact, it is leased rather than assigned by a DHCP server. And this lease is about to expire.
It is one of the most important tasks of the DHCP client to ensure that the interface configuration remains valid. It does this by periodically trying to renew the lease before it expires. The update process uses the same DORA sequence. The only difference is that during the discovery phase, the client requests the same IP address it already has.
Another important function of a DHCP client is the release mechanism. Whenever the client no longer requires its IP address, as it might when it terminates, it will notify the DHCP server to release the IP address so that it can be reused by the server.
DHCP Server Component
As far as a DHCP server is concerned, its main job is to send configuration information to any host that asks for it, and for it to send unique parameters to each individual host. IP addresses can be assigned by a DHCP server in one of three ways: dynamic, automatic, or static.
Dynamic allocation assigns a new IP address to each IP address. Automatic allocation is similar, except that the server will keep track of which IP address has been assigned to each host and will try to assign the same address to it the next time it connects.
Finally, with manual allocation, the administrator must manually associate a specific host identified by its MAC address with a specific IP address. This is also called DHCP reservation because it reserves a specific address for a specific host.
Interaction between DHCP and DNS
Domain Name Service – or DNS – is used to map host names to IP addresses. On a private network that uses DHCP dynamic allocation, there is often some integration between DNS and DHCP. This way, DNS always knows the current IP address of each host.
This is why many DHCP servers also include a DNS server. This applies, for example, to the Microsoft DHCP server, which is fully integrated with the DNS server.
The Comes DDI
DDI is an acronym for DHCP, DNS and IPAM, or IP Address Management. We haven’t discussed the latter yet. IPAM refers to any software used to manage IP addresses. Such systems can typically be used to manage both DHCP assigned addresses and statically assigned addresses that are manually configured on hosts.
With the tight integration that is required between the three, it is quite normal that many vendors have three products built on top of each other, or that they offer all three products separately.