Foundation Summary

The Foundation Summary is a collection of information that provides a convenient review of many key concepts in this chapter. If you are already comfortable with the topics in this chapter, this summary could help you recall a few details. If you just read this chapter, this review should help solidify some key facts. If you are doing your final preparation before the exam, this summarized information is a convenient way to review the day before the exam.

Table 16-5. Commands for Configuring IP Telephony on a Catalyst Switch

Task	Command Syntax
Set power over Ethernet behavior	power inline {auto | never}
Enable QoS globally	mls qos
Define QoS parameter that will be trusted on an interface	mls qos trust {cos | ip-precedence | dscp}
Conditionally trust a Cisco IP Phone	mls qos trust device cisco-phone
Define the trunking on a port to a Cisco IP Phone	switchport voice vlan {vlan-id | dot1p | untagged | none}
Define the trust relationship of the IP Phone	switchport priority extend {cos value | trust}

You can use the commands in Table 16-6 to verify or troubleshoot IP Telephony on a Catalyst switch.

Table 16-6. Commands for Troubleshooting IP Telephony on a Catalyst Switch

Task	Command Syntax
Display Power over Ethernet status	show power inline [type mod/num]
Verify the voice VLAN	show interface type mod/num switchport
Display how QoS trust is extended to the phone	show mls qos interface type mod/num