To ensure IPv4/IPv6 coexistence, Windows enables applications to use IPv6 on an IPv4 network, and it also supports related technologies such as port preservation for Teredo, which is a User Datagram Protocol (UDP)-based tunneling technology that can traverse NATs. This feature enables Teredo communications between “port preserving” symmetric NATs and other types of NATs. A NAT is port preserving if it chooses to use the same external port number as the internal port number.
Current releases of Windows Server support TCP Chimney offloading. This feature enables the networking subsystem to offload the processing of a TCP/IP connection from a server’s processors to its network adapters, as long as the network adapters support TCP/IP offload processing. Both TCP/IPv4 connections and TCP/ IPv6 connections can be offloaded. By default, TCP connections are offloaded on 10-gigabits per second (Gbps) network adapters but are not offloaded on 1-Gbps network adapters. To modify the related settings, you can use Netsh.
Network Diagnostic Framework (NDF) simplifies network troubleshooting by automating many common troubleshooting steps and solutions. When you run Windows Network Diagnostics, each diagnostic session generates a report with diagnostics results, and you can view this information in Action Center by tapping or clicking the Troubleshooting link, and then tapping or clicking View History. On the Troubleshooting History page, each diagnostic session is listed by type and date run. To get detailed information, select the session you want to review, and then tap or click View Details.
The diagnostic information shown in Action Center comes from an Event Trace Log (ETL) file created as part of diagnostics. If you press and hold or right-click a diagnostic session and then select Open File Location, you can view the files generated as part of diagnostics for the selected diagnostic session.
You can use the Netsh Trace context to perform comprehensive tracing in addition to network packet capturing and filtering. You perform traces by using predefined or custom scenarios and providers. Tracing scenarios are collections of providers. Providers are the actual components in the network protocol stack that you want to work with, such as TCP/IP, Windows Filtering Platform and Firewall, Wireless LAN Services, Winsock, or NDIS. Typically, you use Network Monitor (Netmon) to analyze trace data. If you collect trace data on a computer where Netmon isn’t installed, you can just copy the trace file to a computer where Netmon is installed so that you can analyze the data.
Windows Vista with SP1 or later and later releases of Windows use an RDP 6.1 or later compatible client. Here, RDP files can be digitally signed to prevent users from opening or running potentially dangerous RDP files from unknown sources. Administrators can sign RDP files by using a signing tool provided by Microsoft. Three related settings can be configured through Group Policy or through the registry. These settings include a comma-separated list of certificate hashes that are trusted by the administrator (known as the trusted publishers list), an option to enable users to decide to accept untrusted publishers (enabled by default), and an option to enable users to accept unsigned files (enabled by default).
Windows 8.1 and Windows Server 2012 R2 have a number of enhancements in their built-in DNS clients that improve name resolution on IPv4 and IPv6 networks. With adaptive query timeout, the DNS client adapts the timeout interval based on the time required for previous queries. Thus, instead of waiting 1000 milliseconds (ms) before timing out a query, the timeout is adjusted based on past performance for the network, resulting in timeouts between 25 ms and 1000 ms.
The DNS client for Windows 8.1 and Windows Server 2012 R2 also supports query coalescing, parallel queries, and persistent caching. With query coalescing, the DNS client combines multiple DNS queries for the same name. This results in only one query and optimizes performance. With parallel queries, the DNS client issues IPv4 and IPv6 queries for A and AAAA records in parallel when both IP interfaces are enabled, which streamlines the query process and improves performance. Link-local multicast name resolution (LLMNR) and NETBIOS queries are also issued in parallel for IPv4 and IPv6. With a persistent cache, the DNS client maintains the DNS cache across changes that occur on the same network. For example, the DNS client now persists the cache after address change notifications and when the computer is resuming from the sleep or standby state.
Installing TCP/IP networking
To install networking on a computer, you must install TCP/IP networking and a network adapter. Windows Server 2012 R2 uses TCP/IP as the default wide area network (WAN) protocol. Typically, you install networking during Windows Server 2012 R2 setup. You can also install TCP/IP networking through network connection properties.
To install TCP/IP after installing Windows Server 2012 R2, log on to the computer by using an account with administrator privileges, and then follow these steps:
1. In Control Panel, access Network And Sharing Center by tapping or clicking View Network Status And Tasks under the Network And Internet heading.
2. In Network And Sharing Center, tap or click Change Adapter Settings.
3. In Network Connections, press and hold or right-click the connection with which you want to work, and then tap or click Properties. This displays a Properties dialog box for the connection, shown in Figure 7–3.
FIGURE 7–3 Install and configure TCP/IP protocols.
4. If Internet Protocol Version 6 (TCP/IPv6), Internet Protocol Version 4 (TCP/IPv4), or both aren’t shown in the list of installed components, you need to install them. Tap or click Install. Tap or click Protocol, and then tap or click Add. In the Select Network Protocol dialog box, select the protocol to install, and then tap or click OK. If you are installing both TCP/IPv6 and TCP/IPv4, repeat this procedure for each protocol.
5. In the Properties dialog box for the network connection, be sure that Internet Protocol Version 6 (TCP/IPv6), Internet Protocol Version 4 (TCP/IPv4), or both are selected, and then tap or click OK.
6. As necessary, follow the instructions in the next section for configuring network connections for the computer.
Configuring TCP/IP networking
A network connection is created automatically if a computer has a network adapter and is connected to a network. If a computer has multiple network adapters and is connected to a network, one network connection is created for each adapter. If no network connection is available, you should connect the computer to the network or create a different type of connection.
Computers use IP addresses to communicate over TCP/IP. Windows Server 2012 R2 provides the following ways to configure IP addresses:
■ Manually IP addresses that are assigned manually are called static IP addresses. Static IP addresses are fixed and don’t change unless you change them. You usually assign static IP addresses to Windows servers, and when you do this, you need to configure additional information to help the server navigate the network.