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DHCP uses the clients MAC address to determine the IP address a client receives.

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Q: What does dhcp use to determine if a dhcp client has an ip reservation?
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Client computers use DHCP by default unless you specify a dynamic IP address during the installation?

Client computers use DHCP by default unless you specify a static IP address during the installation.


A request by a DHCP client for permission to use the network configuration previously offered by the DHCP server refers to?

A client will request an IP address it had previously in a DHCP Discover or Request message with option 50 marked, and an IP address inserted into the data field of option 50.


Which of the following services does a Windows Deployment Services client computer use to locate a WDS server?

dhcp


How would you describe the DHCP leasing process?

FROM MSDNDHCP Lease ProcessA DHCP-enabled client obtains a lease for an IP address from a DHCP server. Before the lease expires, the DHCP server must renew the lease for the client or the client must obtain a new lease. Leases are retained in the DHCP server database approximately one day after expiration. This grace period protects a client's lease in case the client and server are in different time zones, their internal clocks are not synchronized, or the client is off the network when the lease expires.The DHCP lease process is a process that occurs when a computer which is a DHCP client initially boots up on the network, to provide an IP address and any additional TCP/IP configuration parameters to these clients.The terminology and concepts used when discussing DHCP leasing or the DHCP lease process is summarized below:DHCP lease: This is the amount of time for which a DHCP client is allowed to make use of a specific IP addresses. The default setting for the DHCP lease is 8 days.DHCP lease process: The process which occurs when the client initially boots up on the network. The DHCP lease process enables DHCP clients to automatically obtain IP addresses from a DHCP server.DHCP Discovery Broadcast message: This is a message sent over the network by a client computer that wants to obtain an IP address from a DHCP server.DHCP Offer message: This is message sent by DHCP servers that serves as a reply to a Discovery Broadcast message.DHCP Request Broadcast message: This message indicates that the client accepted an IP address offer from the first DHCP server which responded to it. The client broadcasts this particular message so that all the other DHCP servers that offered addresses to the client can withdraw their IP addresses.DHCP Acknowledge message: This message is sent by the DHCP server to the DHCP client, and is the process whereby which the IP address lease is assigned to the client.Unlimited lease duration: If you do not want the IP address assigned for a particular client to expire, you assign an unlimited lease duration.DHCP scopes: A scope can be defined as a set of IP addresses which the DHCP server can allocate or assign to DHCP clients. A scope contains specific configuration information for clients that have IP addresses which are within a particular scope. Scope information for each DHCP server is specific to that particular DHCP server only, and is not shared between DHCP servers. During the DHCP lease process, the DHCP scopes configured for a DHCP server is used to provide a DHCP client with an IP address.You can configure different lease duration settings for each DHCP scope.The lease duration rules which should be implemented when you determine the lease duration time for the scope of each of your subnets are:Use a shorter lease duration time if you have numerous mobile users, and if you are working in an environment that constantly has configuration changes.Use a longer lease duration time if the following statements are true:There are no mobile computersThe environment does not continually experience configuration changesIncrease the default setting of 8 days if the number of IP addresses for each subnet is by far greater than the number of DHCP devices within your environment.Use a shorter lease duration period if you have a limited number of IP addresses for each subnet, and you are near to meeting limit.Understanding the DHCP Lease ProcessThe DHCP lease process is a four-step process that occurs when a DHCP client initially boots up on the network. The DHCP process remains unchanged since its initial introduction with Windows NT 4.0. During the DHCP lease process, negotiation for an IP address occurs between a DHCP server and a client that needs to obtain an IP address. In a TCP/IP based network, to uniquely identify computers on the network, each computer must have a unique IP address. To communicate on the Internet and private TCP/IP network, all hosts defined on the network must have IP addresses. The 32-bit IP address identifies a particular host on the network. With DHCP, the system assigns IP addresses to clients, which in turn leads to less incorrect configurations of IP addresses. This is mainly due to IP configuration information being entered at one location, and the server distributing this information to clients. Duplicated IP addresses are also prevented.The DHCP lease process that occurs between the DHCP server and client is a simple process. The negotiation process for an IP address consists of four messages sent between the DHCP server and the DHCP client.Two messages from the clientTwo messages from the DHCP serverWhen the server assigns IP addresses to DHCP clients, it starts allocating addresses commencing from the bottom of its scope range, and starts moving to the top of its scope range.All unused addresses have to be used before the DHCP server:Allocates a previously used IP addresses to a new DHCP client. The DHCP server first assigns IP addresses that have not been used for the longest amount of time prior to assigning other previously used IP addresses.Allocates an expired IP addresses to a new DHCP clientDuring the four-step DHCP lease process, the events that occur are defined by the types of DHCP messages which are exchanged between the DHCP server and DHCP client:DHCPDISCOVER message: This message is used to request an IP address lease from a DHCP server. The message is sent when the client boots up on the network. The message is sent as a broadcast packet over the network, requesting for a DHCP server to respond to itDHCPOFFER message: This message is a response to a DHCPDISCOVER message, and is sent by one or numerous DHCP servers.DHCPREQUEST message: The client sends the initial DHCP server which responded to its request a DHCP Request message. The message basically indicates that the client is requesting the particular IP address for lease. The other DHCP servers who offered addresses withdraw those addresses at this point.DHCPACK message: The DHCP Acknowledge message is sent by the DHCP server to the DHCP client and is the process whereby which the DHCP server assigns the IP address lease to the DHCP client.The four steps involved in the DHCP lease process is often called DORA:DiscoverOfferRequestAcknowledge


Describe the integration between DHCP and DNS.?

Traditionally, DNS and DHCP servers have been configured and managed one at a time. Similarly, changing authorization rights for a particular user on a group of devices has meant visiting each one and making configuration changes. DHCP integration with DNS allows the aggregation of these tasks across devices, enabling a company's network services to scale in step with the growth of network users, devices, and policies, while reducing administrative operations and costs.This integration provides practical operational efficiencies that lower total cost of ownership. Creating a DHCP network automatically creates an associated DNS zone, for example, reducing the number of tasks required of network administrators. And integration of DNS and DHCP in the same database instance provides unmatched consistency between service and management views of IP address-centric network services data.Windows Server 2003 DNS supports DHCP by means of the dynamic update of DNS zones. By integrating DHCP and DNS in a DNS deployment, you can provide your network resources with dynamic addressing information stored in DNS. To enable this integration, you can use the Windows Server 2003 DHCP service.The dynamic update standard, specified in RFC 2136: Dynamic Updates in the Domain Name System (DNS UPDATE), automatically updates DNS records. Both Windows Server 2003 and Windows 2000 support dynamic update, and both clients and DHCP servers can send dynamic updates when their IP addresses change.Dynamic update enables a DHCP server to register address (A) and pointer (PTR) resource records on behalf of a DHCP client by using DHCP Client FQDN option 81. Option 81 enables the DHCP client to provide its FQDN to the DHCP server. The DHCP client also provides instructions to the DHCP server describing how to process DNS dynamic updates on behalf of the DHCP client.The DHCP server can dynamically update DNS A and PTR records on behalf of DHCP clients that are not capable of sending option 81 to the DHCP server. You can also configure the DHCP server to discard client A and PTR records when the DHCP client lease is deleted. This reduces the time needed to manage these records manually and provides support for DHCP clients that cannot perform dynamic updates. In addition, dynamic update simplifies the setup of Active Directory by enabling domain controllers to dynamically register SRV resource records.If the DHCP server is configured to perform DNS dynamic updates, it performs one of the following actions:The DHCP server updates resource records at the request of the client. The client requests the DHCP server to update the DNS PTR record on behalf of the client, and the client registers A.The DHCP server updates DNS A and PTR records regardless of whether the client requests this action or not.By itself, dynamic update is not secure because any client can modify DNS records. To secure dynamic updates, you can use the secure dynamic update feature provided in Windows Server 2003. To delete outdated records, you can use the DNS server aging and scavenging feature.


Integration between DHCP and DNS?

Traditionally, DNS and DHCP servers have been configured and managed one at a time. Similarly, changing authorization rights for a particular user on a group of devices has meant visiting each one and making configuration changes. DHCP integration with DNS allows the aggregation of these tasks across devices, enabling a company's network services to scale in step with the growth of network users, devices, and policies, while reducing administrative operations and costs.This integration provides practical operational efficiencies that lower total cost of ownership. Creating a DHCP network automatically creates an associated DNS zone, for example, reducing the number of tasks required of network administrators. And integration of DNS and DHCP in the same database instance provides unmatched consistency between service and management views of IP address-centric network services data.Windows Server 2003 DNS supports DHCP by means of the dynamic update of DNS zones. By integrating DHCP and DNS in a DNS deployment, you can provide your network resources with dynamic addressing information stored in DNS. To enable this integration, you can use the Windows Server 2003 DHCP service.The dynamic update standard, specified in RFC 2136: Dynamic Updates in the Domain Name System (DNS UPDATE), automatically updates DNS records. Both Windows Server 2003 and Windows 2000 support dynamic update, and both clients and DHCP servers can send dynamic updates when their IP addresses change.Dynamic update enables a DHCP server to register address (A) and pointer (PTR) resource records on behalf of a DHCP client by using DHCP Client FQDN option 81. Option 81 enables the DHCP client to provide its FQDN to the DHCP server. The DHCP client also provides instructions to the DHCP server describing how to process DNS dynamic updates on behalf of the DHCP client.The DHCP server can dynamically update DNS A and PTR records on behalf of DHCP clients that are not capable of sending option 81 to the DHCP server. You can also configure the DHCP server to discard client A and PTR records when the DHCP client lease is deleted. This reduces the time needed to manage these records manually and provides support for DHCP clients that cannot perform dynamic updates. In addition, dynamic update simplifies the setup of Active Directory by enabling domain controllers to dynamically register SRV resource records.If the DHCP server is configured to perform DNS dynamic updates, it performs one of the following actions:The DHCP server updates resource records at the request of the client. The client requests the DHCP server to update the DNS PTR record on behalf of the client, and the client registers A.The DHCP server updates DNS A and PTR records regardless of whether the client requests this action or not.By itself, dynamic update is not secure because any client can modify DNS records. To secure dynamic updates, you can use the secure dynamic update feature provided in Windows Server 2003. To delete outdated records, you can use the DNS server aging and scavenging feature.


What services does a windows deployment services client computer use to locate a WDS server?

DHCP DNS DC then contacts WDS


What is the use of a DHCP relay agent?

The use of a DHCP relay agent is an agent that relays DHCP between DHCP clients and DHCP servers on different IP networks. The DHCP relay agent is compliant with RFC 1542.


What intervals do DHCP clients use to perform lease renewals?

renewal time value-after 50 percent of the lease time is expired the DHCP client attempts to renew its lease with the DHCP server that issued the IP address. This renewal time value is referred to as T1 Binding time is value- after 87.5 percent of the lease time has expired the DHCP client attempts to renew it's lease again if unsuccessful, it initiates a DHCPDiscover broadcast request to receive an IP address frt om any DHCP server on its network. this Binding time value is referred to as T 2


Which type of server assigns ip addresses to clients on a temporary or lease basis?

The DHCP server (Dynamic Host Configuration Protocol)What is DHCP?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 (i.e., a scope) configured for a given network. DHCP assigns an IP address when a system is started, for example:A user turns on a computer with a DHCP client.The client computer sends a broadcast request (called a DISCOVER or DHCPDISCOVER), looking for a DHCP server to answer.The router directs the DISCOVER packet to the correct DHCP server.The server receives the DISCOVER packet. Based on availability and usage policies set on the server, the server determines an appropriate address (if any) to give to the client. The server then temporarily reserves that address for the client and sends back to the client an OFFER (or DHCPOFFER) packet, with that address information. The server also configures the client's DNS servers, WINS servers, NTP servers, and sometimes other services as well.The client sends a REQUEST (or DHCPREQUEST) packet, letting the server know that it intends to use the address.The server sends an ACK (or DHCPACK) packet, confirming that the client has a been given a lease on the address for a server-specified period of time.


What is Dora in networking?

The DHCP Server keeps all the information and data base about the DHCP Cliencts. And it works as folows. ________ ________ | | <-----D------------> Discover-------------> | | |DHCP | <-----O------------> Offer----------------> |DHCP | |SERVER | <-----R------------> Request--------------> |CLIENT | |________| <-----A------------> Acknowledgement------> |________| I want further answers regarding this. please do send me. 1. DHCP automatically Discover the systems , 2. Server Send the offer to the client systems , 3. Client send the Request to Server System, 4. last one Acknowledgement send by Server to Client I would like to make an amendment to that so that it is somewhat further understood in it's entirety. 1st: Hardware sends a broadcast asking for information regarding DHCP servers within the network (or Sub-net of course). 2nd. DHCP server responds saying "Hey, I'm here!" 3rd. Hardware sends a query for an IP address (not the same as the request phase.) 4th. DHCP server comes back with "Here ya go, you can have xxx.xxx.xxx.xxx if you want it!" 5th. Hardware decides that's what it wants, so it requests a lease for that IP address. 6th. DHCP server acknowledges the request and assigns a lease time to that piece of hardware (identified by it's MAC address). 1st through 3rd is done through MAC as the hardware has no IP address and cannot communicate through IP. To do those communications before the IP addresses are assigned they use UDP packets with Source and Destination MAC addresses as beginning and end-points. And DHCP servers don't discover the hardware added, the hardware discovers the DHCP servers. That's DORA in a nutshell.


How is the DHCP reservation on a router used?

To enable the router to provide the same IP address to the Telnet server each time it connects to the network. In short, to provide a reliable static IP to use for Telnetting purposes.