Which process the DHCP follows to assign to IP address to client machine?

Dynamic Host Configuration Protocol, or DHCP, is a standard Internet protocol that enables the dynamic configuration of hosts on an Internet Protocol (IP) internetwork.

What is Dynamic Host Configuration Protocol (DHCP)?

DHCP is a standard Internet protocol that enables the dynamic configuration of hosts on an Internet Protocol (IP) internetwork. Dynamic Host Configuration Protocol (DHCP) is an extension of the bootstrap protocol (BOOTP).

How DHCP works

DHCP is a client-server protocol that uses DHCP servers and DHCP clients. A DHCP server is a machine that runs a service that can lease out IP addresses and other TCP/IP information to any client that requests them. For example, on Microsoft Windows NT or Windows 2000 servers, you can install the Microsoft DHCP Server service to perform this function. The DHCP server typically has a pool of IP addresses that it is allowed to distribute to clients, and these clients lease an IP address from the pool for a specific period of time, usually several days. Once the lease is ready to expire, the client contacts the server to arrange for renewal.

DHCP clients are client machines that run special DHCP client software enabling them to communicate with DHCP servers. All versions of Windows include DHCP client software, which is installed when the TCP/IP protocol stack is installed on the machine.

DHCP clients obtain a DHCP lease for an IP address, a subnet mask, and various DHCP options from DHCP servers in a four-step process:

1. DHCPDISCOVER: The client broadcasts a request for a DHCP server. 
2. DHCPOFFER: DHCP servers on the network offer an address to the client. 
3. DHCPREQUEST: The client broadcasts a request to lease an address from one of the offering DHCP servers. 
4. DHCPACK: The DHCP server that the client responds to acknowledges the client, assigns it any configured DHCP options, and updates its DHCP database. The client then initializes and binds its TCP/IP protocol stack and can begin network communication.

The server will quickly and automatically assign an IP address and some related network configuration parameters. Once the device has accepted the assignment, it can communicate with both the internal network and the public internet.

Relevant parameters

In addition to assigning IP addresses, these servers also provide relevant parameters, known as DHCP options. The Internet Assigned Numbers Authority (IANA), the global coordinator of IP addresses, defines available DHCP parameters.

Options number in the hundreds. Key among them is how long the IP address can be used—known as the lease time. They also include the default gateway, its subnet mask, and its DNS server.

Some additional definitions

To clarify, let’s quickly define some of these terms we just mentioned:

• A default gateway transfers data back and forth between the local network and the internet, or between local subnets.
• IP networking uses a subnet mask to separate the host address and the network address portions of an IP address.
• A DNS server resolves names to IP addresses, translating domain names that we easily remember, like bluecatnetworks.com, into IP addresses like 104.239.197.100.

Dynamic IP addressing with DHCP

The assignment of IP addresses happens dynamically within a given address range. As a result, a device connected to the network doesn’t have a forever address. The IP address can periodically change as its lease time expires unless the lease is successfully renewed.

For services that always need to be on, a static IP address is often a better option. Corporate enterprises commonly use static IP addresses for hardware like mail servers. Certainly, a DHCP server should have a static IP address.

However, there are drawbacks to dedicating a specific IP address to a device or service. A network administrator must manually assign, configure, and track the IP address. It’s a time-consuming task. Oftentimes, it requires the admin to physically be with the device.

Meanwhile, dynamic IP addresses are usually the preferred choice because they:

• Cost less to manage than static IP addresses;
• May offer more privacy and security with a constantly changing IP address; and
• Don’t require manual administration when a device roams from one subnet to another.

DHCP communications protocol

Communications to fulfill a DHCP request involves both the server and client. Furthermore, a relay agent or IP helper often facilitates communication between the two. Relay agents receive broadcast DHCP messages from clients and then re-send those messages with configuration information to servers.

Communication happens via small units of data, called packets, that are routed through a network. Networking protocols like IP govern all its rules.

Most of the time, communication occurs in four steps. Briefly, they are:

1. A discover packet is sent from the client to the server.
2. The server replies to the client with a DHCP offer packet containing an IP address.
3. The client receives and validates the offer, then sends a request packet back to the server to accept the address.
4. The server sends an acknowledgement packet back to the client to confirm the chosen IP address.

With this in mind, one final point: DHCP alongside DNS and IP address management (IPAM) are together known as DDI. Want to know how to define DDI or how it works to form a complete management solution? The BlueCat platform is the place to start.

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Which process is followed by DHCP to provide IP addresses to clients?

The process for obtaining DHCP configuration information is pretty simple: Discover, Offer, Request, and Acknowledge (DORA). The DHCP client broadcasts a message called a DHCP discover message. The server will reply with a DHCP offer message that includes an offered IP address, subnet mask, and some other data.

What is the DHCP process for client machine?

Dynamic Host Configuration Protocol (DHCP) is a standard protocol defined by RFC 1541 (which is superseded by RFC 2131) that allows a server to dynamically distribute IP addressing and configuration information to clients. Normally the DHCP server provides the client with at least this basic information: IP Address.

How does DHCP assign IP address automatically?

Dynamic Host Configuration Protocol (DHCP) is a network protocol that enables a server to automatically assign an IP address to a computer from a defined range of numbers (that is, a scope) configured for a given network.

What is the process of obtaining IP address via DHCP?

How do I obtain an IP address automatically from the DHCP server?.

Right Click Windows Start. ... .

From the menu, click Control Panel..

Select Network and Sharing Center..

Select Change adapter settings..

Select Etherent..

Select Properties..

Tab on Internet Protocol Version 4 (TCP/Ipv4), then click on Properties..