Microsoft Networking Technology

The Windows Routing Table

The Windows Routing Table

When routers have to ahead packets, they interpret the packets’ addresses then use the knowledge within the routing tables to cross the packet on. Knowledge packets include each supply and vacation spot addresses of their packet headers. That is the knowledge that’s used when routing selections must be made.

The vacation spot handle is in contrast with the native handle to find out the next info on how you can route the packet:

  • Ought to the packet be despatched up the stack on the native host?
  • Ought to the packet be despatched to a special vacation spot?
  • Ought to the packet merely be ignored?

The routing desk incorporates route entries. The several types of routes within the routing are:

  • Host route: A number route supplies a path to both of the next locations:
    • Particular vacation spot host
    • Broadcast tackle

    Host routes are recognized within the routing desk by a community masks of 255.255.255.255.

  • Community route: A community route offers a path to the next vacation spot:
    • Particular vacation spot community

    Community routes are recognized within the routing desk by a subnet masks between zero.zero.zero.zero and 255.255.255.255.

  • Default route: Every routing desk consists of one default route. When a packet is acquired that has a vacation spot handle that doesn’t correspond to any tackle within the routing desk, the default route is used to ahead this packet. The default route is recognized within the routing desk by a zero.zero.zero.zero handle and a zero.zero.zero.zero community masks.

Customers can view the IP routing desk’s content material from:

  • Routing and Distant Entry administration console
    1. Click on Begin, Administrative Instruments, and click on Routing and Distant Entry to open the Routing and Distant Entry console.
    2. Within the console tree, increase the IP Routing node.
    3. Proper-click the Static Routes node, then choose Present IP Routing Table from the shortcut menu.
    4. The entries within the routing desk are displayed in the appropriate pane of the Routing and Distant Entry console.
  • Command line
    1. Open a command line window
    2. Enter route print

With static routing, directors need to manually create and modify the routing desk entries. Every time a change happens within the community configuration, the entries within the routing desk should be modified to mirror these modifications. Static routing works properly in a small community the place it’s simpler to configure a small variety of static routes than it’s to configure dynamic routing.

With dynamic routing, routing protocols allow IP routers to speak with one another. The routing protocols additionally allow routers to share the knowledge they’ve of their routing tables. A router that’s configured to make use of dynamic routing forwards its routing desk’s content material to the opposite routers configured for dynamic routing at common time durations or intervals.

Understanding the Windows 2000 and Windows XP Routing Tables

The Windows 2000 and Windows XP routing desk can nevertheless solely be accessed from a command line. The Routing and Distant Entry administration console can’t be used to view the contents of a Windows 2000 routing desk and Windows XP routing desk.

The normal fields in a Windows 2000 routing desk and Windows XP routing desk are:

  • Community Vacation spot: The Community Vacation spot subject incorporates entries that the router compares to every packet’s vacation spot handle that it receives. A few of these entries, just like the default route entry, are the identical for many routing tables.
    The community ID for the route might be both of the next:
    • IP handle for a number
    • Subnet handle
    • Supernet tackle
    • Class-based handle
  • Netmask: That is the ask used to affiliate the vacation spot handle with the community vacation spot. The Netmask worth principally specifies what factor of the vacation spot tackle of the packet is matched to the Community Vacation spot entries. The largest match determines the route that will probably be utilized to a selected IP packet.
  • Gateway: After a route is utilized to an IP packet, the worth specified within the Gateway subject defines the forwarding or next-hop IP handle that the packet will use for the community vacation spot.
  • Interface: The worth of the Interface subject defines the IP handle of the community interface card (NIC) used to ahead the packet to the subsequent hop.
  • Metric: The worth within the Metric area signifies the price of utilizing the route. The metric determines which route is utilized among the many totally different route choices.

The further fields that may be current within the Windows 2000 routing desk and Windows XP routing desk are:

  • Instantly Hooked up Community ID Routes: This info is used for all routes which are immediately hooked up. On this case, the Gateway IP handle is the interface’s IP tackle on the precise community for all networks which are hooked up.
  • Distant Community ID Routes: This info is used for these routes which are out there by way of different routers. The routes are subsequently indirectly obtainable. Right here, the Gateway IP handle is the native router’s IP tackle that’s situated between the forwarding node and the distant community.
  • Host Routes: This subject permits customers to enter a path to a selected vacation spot host. On this case, the community vacation spot is the precise host’s IP tackle. The subnet masks is 255.255.255.255.
  • Default Route: Customers can enter a default route that shall be used to ahead packets the place the community ID or host route can’t be discovered within the routing desk. On this case, the community vacation spot is zero.zero.zero.zero. The subnet masks is zero.zero.zero.zero.

Find out how to view a Windows 2000 routing desk or Windows XP routing desk:

  1. Click on Begin, Run, enter cmd, then press Enter to open a command immediate window.
  2. Enter the command route assist to show the totally different instructions that can be utilized with the route command. Press Enter.
  3. To view the routing desk, enter route print.
  4. The default routing desk entries are created every time the TCP/IP protocol begins on the precise pc.
  5. The default route ought to be displayed as zero.zero.zero.zero with the subnet masks of zero.zero.zero.zero.
  6. The loopback route must be displayed as 127.zero.zero.zero with a subnet masks of 255.zero.zero.zero and gateway 127.zero.zero.1.
  7. The Community Vacation spot column ought to include a route entry for the native pc.
  8. Enter exit to shut the command immediate window.

The best way to add routing desk entries with the route command:

  1. Click on Begin, Run, enter cmd, then press Enter to open a command immediate window.
  2. Enter the command route assist to show the totally different instructions that can be utilized with the route command. Press Enter.
  3. The command line format used so as to add a routing desk entry is:
    • route add [destination] [mask] [gateway] [metric] IF [interface]
  4. To confirm that the right routing desk entry was added, enter route print to view the routing desk.
  5. If the wrong gateway or metric was entered, use the route change command to switch these values.
  6. If another info was incorrectly entered, use the route delete command to delete the precise entry and the route add command to re-enter the routing desk entry.

Tips on how to delete routing desk entries:

  1. Click on Begin, Run, enter cmd, and press Enter to open a command immediate window.
  2. The command line format to delete a routing desk entry is:
    • route delete [destination]/code>
  3. To confirm that the right routing desk entry was deleted, enter route print to view the routing desk.

Understanding the Windows Server 2003 Routing Table

The Windows Server 2003 routing desk accommodates the next normal fields:

  • Community Vacation spot
  • Netmask
  • Gateway
  • Interface
  • Metric
  • Protocol

With Windows Server 2003, view the routing desk utilizing:

  • The route command from the command line. The route instructions in Windows 2000, Windows XP, and Windows Server 2003 are all the identical.
  • The Routing and Distant Entry administration console. Entry the Routing and Distant Entry console by clicking Begin, Administrative Instruments, and Routing and Distant Entry.

The major variations between the earlier routing tables and the Windows Server 2003 routing tables are listed under:

  • With Windows Server 2003, the routing metric is mechanically calculated by the TCP/IP protocol. The interface’s velocity determines the routing metric. The function is routinely enabled by default.
  • With the earlier routing tables, the netmask for the Class D multi-cast is specified as 224.zero.zero.zero. With Windows Server 2003 routing tables, the netmask for the Class D multi-cast is specified as 240.zero.zero.zero.
  • The routing tables in Windows Server 2003 may be seen and maintained by means of the Routing and Distant Entry administration console. In Windows 2000 and Windows XP, routing tables can solely be seen and modified from the command line with the route command.

Find out how to view the routing desk in Window Server 2003:

  1. Click on Begin, Administrative Instruments, and Routing and Distant Entry to open the Routing and Distant Entry console.
  2. Within the console tree, increase the IP Routing node.
  3. Proper-click the Static Routes node and choose the Present IP Routing Table command from the shortcut menu.
  4. When the routing desk is seen from the Routing and Distant Entry console, the Protocol subject is displayed. The Protocol area signifies the way by which the route was found.

The best way to add routing desk entries with the Routing and Distant Entry console:

  1. Click on Begin, Administrative Instruments, and Routing and Distant Entry to open the Routing and Distant Entry console.
  2. Within the console tree, increase the IP Routing node.
  3. To view the routing desk for an interface, right-click the precise interface then choose Present IP routing Table from the shortcut menu.
  4. So as to add a static routing desk entry, increase the IP Routing node then choose Static Routes.
  5. Proper click on Static Routes and click on Add Static Route on the shortcut menu.
  6. The Static Route dialog field opens.
  7. From the Interface drop-down record field, choose the interface.
  8. Enter a worth for Vacation spot.
  9. Enter a worth for Community masks.
  10. Enter a worth for Gateway.
  11. Enter a worth for Metric.
  12. Depart the demand-dial connections check-box enabled if the route is for use for demand-dial connections.
  13. Click on OK.

The right way to Delete Routing Table Entries with the Routing and Distant Entry Console

  1. Click on Begin, Administrative Instruments, and Routing and Distant Entry to open the Routing and Distant Entry console.
  2. Within the console tree, increase the IP Routing node.
  3. Choose Static Routes to show the present static routes in the best pane.
  4. Find and choose the static path to be faraway from the IP routing desk.
  5. Proper-click the precise static route then choose Delete from the shortcut menu.
  6. The static route is instantly faraway from the routing desk.

How one can disable the automated metric calculation function:

  1. Click on Begin, Management Panel, and Community Connections.
    Choose Native Space Connection.
  2. The Native Space Connection Properties dialog field opens.
  3. Within the This connection makes use of the next gadgets field, choose the Web Protocol (TCP/IP). Click on Properties.
  4. When the Web Protocol (TCP/IP) Properties dialog field opens, click on Superior.
  5. The Superior TCP/IP Settings dialog field accommodates numerous tabs: IP Settings tab, DNS tab, WINS tab, and Choices tab.
  6. The IP Settings tab is split into the next areas:
    • IP addresses
    • Default gateways
    • Automated metric
  7. Within the Automated metric space of the IP Settings tab, uncheck the Automated metric check-box to disable the automated metric calculation function.
  8. Manually enter the Interface metric as soon as the automated metric calculation function is disabled.
  9. Set the worth for the Interface metric within the obtainable area.
  10. Click on OK to save lots of the modifications and shut the Superior TCP/IP Settings dialog field.
  11. Click on OK to shut the Web Protocol (TCP/IP) Properties dialog field.
  12. Click on OK to shut the Native Space Connection Properties dialog field.