Cisco Router 800 Series Software Configuration Guide

 
7-31
Cisco 800 Series Software Configuration Guide
78-5372-06
Chapter 7      Router Feature Configuration
Configuring DHCP
For more information on the features not used in this configuration, refer to the 
Cisco IOS DHCP Server feature module. For more general information on DHCP 
servers, refer to Chapter 1, “Concepts.” 
Configuration Example
The following configuration shows a DHCP server configuration for the IP 
address 20.1.1.2.
!
ip dhcp pool CLIENT
   network 20.20.20.0 255.255.255.0...

 
Chapter 7      Router Feature Configuration
Configuring DHCP
7-32
Cisco 800 Series Software Configuration Guide
78-5372-06
Follow the steps below to configure the DHCP relay, beginning in global 
configuration mode.
For complete information on the DHCP relay commands, refer to the 
Cisco IOS Release 12.0 documentation set. For more general information on 
DHCP relays, refer to Chapter 1, “Concepts.” 
Configuration Example
The following configuration contains commands relevant to DHCP relay only. 
You...

 
7-33
Cisco 800 Series Software Configuration Guide
78-5372-06
Chapter 7      Router Feature Configuration
Configuring TACACS+
Verifying Your Configuration 
To verify that you have properly configured the DHCP relay, enter the 
show dhcp server command. You should see verification output like the example 
shown below. 
router#sh dhcp server 
   DHCP server:2.2.2.2
    Leases:  0
    Offers:  0      Requests:0     Acks:0     Naks:0
Declines:0      Releases:0     Bad: 0
Configuring TACACS+
The Cisco 806,...

 
Chapter 7      Router Feature Configuration
Configuring an Extended Access List
7-34
Cisco 800 Series Software Configuration Guide
78-5372-06
You may need to perform other configuration steps to enable accounting for 
TACACS+ connections. For instructions on configuring TACACS+, refer to the 
Security Configuration Guide.
Configuring an Extended Access List
Follow the steps below to include one or more extended access lists in your router 
configuration, beginning in global configuration mode.
Step...

 
7-35
Cisco 800 Series Software Configuration Guide
78-5372-06
Chapter 7      Router Feature Configuration
Configuring an Extended Access List
For more complete information on the extended access list commands, refer to the 
Cisco IOS Release 12.0 documentation set. For information on TCP and UDP 
port assignments, see Appendix C, “Common Port Assignments.”
Configuration Example
This configuration shows an access list being applied to IP address 192.168.1.0.
You do not need to enter the commands marked...

 
Chapter 7      Router Feature Configuration
Configuring Quality of Service Parameters
7-36
Cisco 800 Series Software Configuration Guide
78-5372-06
Configuring Quality of Service Parameters
This section describes how to configure quality of service (QoS) parameters. The 
following are requirements for voice QoS:
Priority queuing for voice traffic
Fragmenting large data packets and interleaving voice packets
You can configure QoS in a single- or multiple-PVC environment. In a 
single-PVC environment,...

 
7-37
Cisco 800 Series Software Configuration Guide
78-5372-06
Chapter 7      Router Feature Configuration
Configuring Quality of Service Parameters
Configuring IP Precedence
IP Precedence gives voice packets a higher priority than other IP data traffic. The 
ip precedence command is used by the router to differentiate voice traffic from 
data traffic. Therefore, you need to ensure that the data IP packets do not have the 
same IP precedence as that of the voice packets.
Follow the steps below to...

 
Chapter 7      Router Feature Configuration
Configuring Quality of Service Parameters
7-38
Cisco 800 Series Software Configuration Guide
78-5372-06
Configuring a Policy Map and Specifing Voice Queuing
Follow the steps below to configure a policy map and to specify voice queuing, 
beginning in global configuration mode.
Configuring a Policy Map and Specifying Priority Queuing for Voice Class
Follow the steps below to associate the policy map to the ATM PVC and decrease 
the MTU of the ATM interface so...

 
7-39
Cisco 800 Series Software Configuration Guide
78-5372-06
Chapter 7      Router Feature Configuration
Configuring Quality of Service Parameters
Associating the Policy Map to the ATM PVC and Decreasing the ATM Interface 
MTU
Use the following table to associate the policy map to the ATM PVC and decrease 
the MTU, beginning in global configuration mode. It is recommended that 300 is 
used for the MTU size because it is larger than the size of the voice packets 
generated by the different codecs....

 
Chapter 7      Router Feature Configuration
Configuring a Single-PVC Environment Using RFC 1483 Encapsulation
7-40
Cisco 800 Series Software Configuration Guide
78-5372-06
Configuration Example
The following example shows a voice QoS configuration in a single-PVC 
environment using AAL5SNAP encapsulation.
!
dial-peer voice 105 voip  
destination-pattern 3.. 
session target ipv4:10.1.2.3 
ip precedence 5
access-list 101 permit ip any any precedence critical
class-map voice  
match access-group 101...