Cisco Router 800 Series Software Configuration Guide
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3-27 Cisco 800 Series Software Configuration Guide 78-5372-06 Chapter 3 Configuring Advanced Networks Controlling the DDR ISDN Line Activation UDP broadcasts associated with networks running DHCP relay UDP broadcasts associated with NTP IP broadcasts, including RIP and EIGRP broadcasts The following sections describe how to control these types of traffic. UDP Broadcasts in Windows Networks The “Configuring UDP Broadcasts” section on page 3-23 describes how to configure the router to forward...
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Chapter 3 Configuring Advanced Networks Controlling the DDR ISDN Line Activation 3-28 Cisco 800 Series Software Configuration Guide 78-5372-06 NoteThis example of an extended access list includes commonly anticipated restrictions. The information in this section is meant to be used as a base from which you can add or delete restrictions as appropriate for your particular network. The extended access list that you create depends on your particular network. UDP Broadcasts in DHCP Relay...
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3-29 Cisco 800 Series Software Configuration Guide 78-5372-06 Chapter 3 Configuring Advanced Networks Controlling the DDR ISDN Line Activation UDP Broadcasts in NTP Environment You can configure an extended access list so that UDP broadcasts associated with NTP do not activate the ISDN line. An extended access list controls packets. When defining this list, you can specify complex addresses and can permit or deny specific protocols. Configuration Starting in global configuration mode, use the...
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Chapter 3 Configuring Advanced Networks Controlling the DDR ISDN Line Activation 3-30 Cisco 800 Series Software Configuration Guide 78-5372-06 IP Traffic You can configure an extended access list so that IP broadcasts, including RIP and EIGRP broadcasts, do not activate the ISDN line. An extended access list controls packets. When defining this list, you can specify complex addresses and permit or deny specific protocols. Configuration Starting in global configuration mode, use the following...
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3-31 Cisco 800 Series Software Configuration Guide 78-5372-06 Chapter 3 Configuring Advanced Networks Restricting Access to Your Network Restricting Access to Your Network You can restrict access to your network by creating an extended access list. An extended access list controls packets. When defining this list, you can specify complex addresses and permit or deny specific protocols. Figure 3-5 and Ta b l e 3 - 5 show an example of a network with restricted access. See Ta b l e 3 - 1 for...
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Chapter 3 Configuring Advanced Networks Restricting Access to Your Network 3-32 Cisco 800 Series Software Configuration Guide 78-5372-06 Configuration of Extended Access List Starting in global configuration mode, use the following steps to set up an extended access list based on the restrictions in Ta b l e 3 - 1. For information on the commands used in this table, refer to the Cisco IOS documentation. Callout Number Description 1SMTP mail server 2We b s e r v e r 3FTP server 4Internet...
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3-33 Cisco 800 Series Software Configuration Guide 78-5372-06 Chapter 3 Configuring Advanced Networks Restricting Access to Your Network Command Purpose Step 1router# configure terminalEnter global configuration mode. Step 2router(config)# interface bri0Change to interface configuration mode for the WAN interface. Step 3router(config-if)# dialer-group 1Create a dialer list. Step 4router(config-if)# exitReturn to global configuration mode. Step 5router(config)# access-list 100 permit tcp any...
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Chapter 3 Configuring Advanced Networks Restricting Access to Your Network 3-34 Cisco 800 Series Software Configuration Guide 78-5372-06
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CHAPTER 4-1 Cisco 800 Series Software Configuration Guide 78-5372-06 4 Network Scenarios This chapter provides sample network scenarios and configurations using Cisco 800 series and Cisco SOHO series routers. This chapter is useful if you are building a new network and want examples of features or configurations. If you already have a network set up and you want to add specific features, see Chapter 7, “Router Feature Configuration.” This chapter includes the following sections: Cisco 827 Router...
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Chapter 4 Network Scenarios Cisco 827 Router Network Connections 4-2 Cisco 800 Series Software Configuration Guide 78-5372-06 Cisco 827 Router Network Connections Figure 4-1 and Ta b l e 4 - 1 illustrate an example of a network topology employing a Cisco 827 router connecting to the following: Public switched telephone network (PSTN) Corporate intranet Service provider on the Internet Service provider data center Figure 4-1 Cisco 827 Router Network Connections DSLAMCisco 7200 Cisco...