DHCP Lease Process

The first time that a  client (with DHCP enabled) attempts to join a network, it automatically follows an initialization process to obtain a lease from a DHCP server.

1. The DHCP client requests an IP address by broadcasting a message (known as a DHCPDiscover message) to the local subnet.
2. The client is offered an address when a DHCP server responds with a DHCPOffer message containing an IP address, and associated configuration information, available for lease to the client.
3. The client selects the offered address and replies to the server with a DHCPRequest message. Alternatively, the DHCP client might request the IP address that was previously assigned.
4. The client is assigned the address, and the DHCP server sends an acknowledgment message (DHCPAck) approving the lease. Other DHCP option information, such as default gateway and DNS server addresses, might be included in the message.

After the client receives acknowledgment, it configures its TCP/IP properties using any DHCP option information in the DHCPAck message and completes the initialization of TCP/IP.

If no DHCP server responds to the client request, the client can proceed in one of two ways:

1. If APIPA is enabled, the client self-configures a unique IP address in the range 169.254.0.1 through 169.254.255.254.
2. If APIPA has been disabled, the client network initialization fails. The client continues to re-send DHCPDiscover messages in the background until it receives a valid lease from a DHCP server. The client makes four attempts to obtain a lease, one every five minutes.

Configuring Clients for Stateful or Stateless IPv6 Addressing

By default, IPv6 hosts perform stateless address auto configuration automatically.

•    In the DHCPv6 stateless mode clients use DHCPv6 to obtain only configuration options and not an IPv6 address. Stateless clients configure an IPv6 address through a non–DHCPv6-based mechanism, such as by exchanging Router Solicitation and Router Advertisement messages with neighboring routers.

•    In the DHCPv6 stateful mode, clients acquire both the IPv6 address as well as other network configuration parameters through DHCPv6.

Windows 8 Developer Preview downloads

You can get it from the following link:

http://dev.windows.com/

It will be available in x86 (32 or 64 bit) and there will be no activation required.

How DNS works

GlobalName Zones

The GlobalNames Zone is a new feature in Windows 2008 and R2 that provides single-label name resolution for large enterprise networks that do not deploy WINS and where using DNS name suffixes to provide single-label name resolution is not practical.
Today, numerous Microsoft customers deploy WINS technology and servers in their environment. WINS is an alternative name resolution protocol to DNS. It is an older service that uses NetBIOS over TCP/IP (NetBT). WINS and NetBT do not support IPv6 protocols. To help customers migrate to DNS for all name resolution the DNS Server role in Windows Server 2008 supports a special GlobalNames Zone (GNZ) feature.

Link

Name Resolution

Windows 2008/R2 and Windows 7 use three types of name resolution system:

1) Link Local Multicast Name Resolution (LLMNR)
2) NetBIOS
3) Domain Name System (DNS)

DNS is the preferred name resolution system in Windows networks and used whenever is available.

How to install and uninstall IPv6 on Windows XP

1. To install IPv6 on your Windows XP computer, follow these steps:
• Click Start, click All Programs, click Accessories, and then click Command Prompt.
• At the command prompt, type netsh int ipv6 install and press the Enter key on your keyboard.
• Close the Command Prompt window.

2. To uninstall IPv6 on your Windows XP computer, follow these steps:
• Click Start, click All Programs, click Accessories, and then click Command Prompt.
• At the command prompt, type: netsh int ipv6 uninstall and press the Enter key on your keyboard.
• Close the Command Prompt window and restart the computer.