Table Of Contents
Related Features and Technologies
Supported Standards, MIBs, and RFCs
Configuring a Voice Port to Monitor the Link to a Remote Interface
Configuring a Hard or Soft Busyout
Configuring a Voice Class for Local Voice Busyout
Assigning a Voice Class to a Voice Port
Configuring a Voice Class on the Cisco AS5300, Cisco AS5350, and Cisco AS5400
Assigning a Voice Class to a DS-0/PRI Groups
Verifying the AVBO Configuration
Configuring a Soft Busyout Example
Configuring a Hard Busyout Example
Configuring a Voice Port to Monitor the Link to a Remote Interface Examples
Configuring a Voice Class for Local Voice Busyout Examples
Advanced Voice Busyout
Feature History
This feature module describes advanced voice busyout functions in Cisco IOS Release 12.2(4)T. It includes the following sections:
•Supported Standards, MIBs, and RFCs
Feature Overview
The local voice busyout feature provides a way to busy out a voice port or DS-0 group (time slot) if a state change is detected in a monitored network interface (or interfaces). When a monitored interface changes to a specified state—to out-of-service or in-service—the voice port presents a seized/busyout condition to the attached PBX or other customer premises equipment (CPE). The PBX or other CPE can then attempt to select an alternate route.
Advanced Voice Busyout (AVBO)
Cisco 2600 Series, Cisco 3600 Series, Cisco 7200 Series and Cisco MC3810
Advanced Voice Busyout adds the following functionality to the local voice busyout feature:
•For Voice over IP (VoIP), monitoring of links to remote, IP-addressable interfaces by use of service assurance agent (SAA)
•Configuration by voice class to simplify and speed up the configuration of voice busyout on multiple voice ports
Using the Advanced Voice Busyout feature you can perform the following tasks:
•Configure individual voice ports to enter the busyout state if an SAA probe signal returned from a remote, IP-addressable interface detects loss of IP connectivity by crossing a specified delay or loss threshold.
•Define voice classes with specified busyout conditions, and assign a particular voice class to any number of voice ports.
•SAA probe monitoring of remote interfaces is intended for use with VoIP networks, although it can also be used with Voice over Frame Relay (VoFR) and Voice over ATM (VoATM) networks.
Cisco AS5300, Cisco AS5350, and Cisco AS5400
Advanced Voice Busyout adds the following functionality:
•Monitoring of links to remote, IP-addressable interfaces by use of SAA
•Configuration by voice class to simplify and speed up the configuration of voice busyout on DS-0/PRI groups.
The Advanced Voice Busyout feature allows you to perform the following tasks:
•Configure individual DS-0/PRI groups under individual T1/E1 controllers to enter the busyout state if an SAA probe signal returned from a remote, IP-addressable interface detects loss of IP connectivity by crossing a specified delay or loss threshold
•Define voice classes with specified busyout conditions, and assign a specific voice class to DS-0/PRI groups.
SAA probe monitoring of remote interfaces is intended for use with VoIP networks, although it can also be used with Voice over Frame Relay (VoFR) and Voice over ATM (VoATM) networks.
Note The 12.2(4)T release does not support the Cisco AS5300, Cisco AS5350 or Cisco AS5400.
Soft/Hard Busy
This feature allows an Internet service provider (ISP) to manually busyout certain channels/channel-groups or trunk groups.
The existing ds0 busyout command has been enhanced to support the soft/hard manual busyout feature. The existing isdn service command can be used to manually soft-busy PRI groups. These commands are usable on individual DS-0s.
Note This feature does not support commands which can busyout a trunk group.
Benefits
The AVBO feature provides the following benefits:
•Reduces the number of configuration steps when multiple voice ports are configured for the same busyout triggering conditions
•Adds additional busyout triggering conditions.
•Increases the flexibility of the call fallback feature.
•Soft busyout enables ISPs to manually busy out certain channels and/or channel groups, or trunk groups.
Restrictions
The following restrictions and limitations apply to the AVBO feature:
•A maximum of 128 network interfaces can be monitored for a voice port.
•The maximum number of simultaneous SAA probes is controlled by the SAA sub-system design and its configuration.
•Busyout based on monitoring of a remote, IP-addressable interface is not activated by the following conditions:
–Non availability of DSP resources
–Non availability of bandwidth
•Call fallback must be enabled for the busyout monitor probe command to function.
•The SAA responder function must be enabled on the router at the remote IP address targeted by the SAA probe.
•This feature is not supported on the BRI voice module (BVM).
Related Features and Technologies
•Local Voice Busyout
•Service Assurance Agent
•PSTN Fallback Feature
Related Documents
•Cisco IOS Voice, Video, and Fax Configuration Guide, Cisco IOS Release 12.2
•Cisco IOS Voice, Video, and Fax Command Reference, Cisco IOS Release 12.2
Supported Platforms
This feature is supported on the following Cisco platforms:
•Cisco 2600 series
•Cisco 3600 series
•Cisco 7200 series
•Cisco MC3810
•Cisco AS5300
•Cisco AS5350
•Cisco AS5400
Note The 12.2(4)T release does not support the Cisco AS5300, Cisco AS5350 or Cisco AS5400.
Table 1 lists the hardware platforms that support this feature, and the releases in which the feature was first supported. If the First T train Release column is blank, the feature is not yet available in a Cisco IOS T release on that platform.
Determining Platform Support Through Feature Navigator
Cisco IOS software is packaged in feature sets that support specific platforms. To get updated information regarding platform support for this feature, access Feature Navigator. Feature Navigator dynamically updates the list of supported platforms as new platform support is added for the feature.
Feature Navigator is a web-based tool that enables you to quickly determine which Cisco IOS software images support a specific set of features and which features are supported in a specific Cisco IOS image.
Feature Navigator is updated regularly when major Cisco IOS software releases and technology releases occur. For the most current information, go to the Feature Navigator home page at the following URL:
Supported Standards, MIBs, and RFCs
Standards
ITU-T G.113 General Characteristics of International Telephone Connections and International Telephone Circuits
MIBs
No new or modified MIBs are supported by this feature.
To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
RFCs
No new or modified RFCs are supported by this feature.
Prerequisites
The Cisco AS5350 and Cisco AS5400 do not support the MICA modem card, Microcom modem card, or VoIP feature card. Voice and modem functions are provided by the Universal Port Dial Feature card running SPE firmware. See the Cisco AS5350 Universal Gateway Card Installation Guide and the Cisco AS5400 Universal Gateway Card Installation Guide for more information. All references to the Cisco AS5300 in this document apply to the Cisco AS5350 and Cisco AS5400 platforms with the following exceptions:
•Use the Universal Port Dial feature card instead of the MICA or Microcom modem cards.
•Use SPE firmware instead of portware version 6.7.7.
•Use Cisco IOS Release 12.2(4)T or later.
Other Prerequisites
You should complete the following configuration tasks before configuring the AVBO feature:
•Voice over IP configuration, including the configuration of POTS and network dial peers
•Voice port configuration
If the SAA probe function is to be implemented, you must configure the following:
•A VoIP network
•Call fallback on the local router
•The SAA responder on the target (far-end) router
Configuration Tasks
See the following sections for the configuration tasks for the AVBO feature. Each task in the list is identified as either optional or required:
Cisco 2600 Series, Cisco 3600 Series, Cisco 7200 Series, and Cisco MC3810
Complete the following task to configure a voice port to enter the busyout state if an SAA probe signal returned from a remote, IP-addressable interface crosses a specified delay or loss threshold:
•Configuring a Voice Port to Monitor the Link to a Remote Interface (required)
Complete the following tasks to configure a hard or soft busyout:
•Configuring a Hard or Soft Busyout (optional)
Complete the following task to define a voice class with specified busyout conditions, and assign a particular voice class to any number of voice ports:
•Configuring a Voice Class for Local Voice Busyout (required)
Complete the following task to assign a voice class to a voice port:
•Assigning a Voice Class to a Voice Port (required)
Cisco AS5300, Cisco AS5350, Cisco AS5400
The following procedure configures DS-0/PRI groups under a T1/E1 controller for AVBO. When properly configured, the DS-0/PRI groups specified busyout if the SAA probe targeted towards a remote interface does not return or returns with delay/jitter values above those specified in the configuration criteria.
•Configuring a Voice Class on the Cisco AS5300, Cisco AS5350, and Cisco AS5400 (required)
•Assigning a Voice Class to a DS-0/PRI Groups (required)
All Platforms
•Verifying the AVBO Configuration (optional)
Configuring a Voice Port to Monitor the Link to a Remote Interface
You can configure voice ports individually for busyout, or you can apply a voice class that includes all of the busyout parameters (see the "Configuring a Voice Class for Local Voice Busyout" and the "Assigning a Voice Class to a Voice Port").
Note If you have already assigned a busyout voice class to a voice port, you cannot configure busyout using this procedure; the command will be rejected.
To configure a voice port to go into the busyout state when the SAA probe signal returned from a remote interface crosses a predetermined threshold, complete the following steps beginning in global configuration mode:
Configuring a Hard or Soft Busyout
To configure a DS-0 time slot on a T1 or E1 controller for a hard or soft busyout state, complete the following steps beginning in global configuration mode.
Configuring a Voice Class for Local Voice Busyout
A busyout voice class can provide monitoring of local ports and links to remote IP addresses. Busyout occurs when all the monitored local ports are out of service or when all of the monitored links go below the threshold.
To define a voice class with specified busyout conditions, complete the following steps beginning in global configuration mode:
After you have created the voice class for busyout function, assign it to all of the voice ports that have these busyout requirements. See "Assigning a Voice Class to a Voice Port" section.
Assigning a Voice Class to a Voice Port
To assign a particular voice class to a voice port, complete the following steps beginning in global configuration mode:
Repeat the above procedure for each voice port to be configured for busyout.
Configuring a Voice Class on the Cisco AS5300, Cisco AS5350, and Cisco AS5400
To define a voice class with specified busyout conditions, complete the following steps beginning in global configuration mode:
After you have created the voice class for busyout function, assign it to the DS-0/PRI groups that have these busyout requirements, using the procedure that follows.
Assigning a Voice Class to a DS-0/PRI Groups
To assign a specific voice class to a DS-0/PRI groups, complete the following steps beginning in global configuration mode:
Repeat the above procedure for each DS-0 group to be configured for busyout. There is only one PRI group.
Verifying the AVBO Configuration
Complete the following tasks to verify that a voice port is correctly configured to monitor the link to a remote interface:
Step 1 Shut down the remote interface associated with the configured IP address. This should cause the voice port to busy out.
Step 2 Enter the show voice busyout command to display information about the busyout state.
The following is a sample display from the show voice busyout command for voice ports on a Cisco 7200:
Router# show voice busyoutVoice port busyout will be triggered by thefollowing network interfaces states3/0:0 busyout monitor FastEthernet0/03/1:0 probe 209.165.202.128 codec g711u icpif 253/2:0 probe 209.165.202.128 codec g711u icpif 253/3:0 probe 209.165.202.128 codec g711u icpif 25The following voice ports are in busyout state1/1:1 is in busyout state caused byprobe 209.165.202.128 codec g711u icpif 21/2:2 is in busyout state caused byprobe 209.165.202.128 codec g711u icpif 21/1:3 is in busyout state caused byprobe 209.165.202.128 codec g711u icpif 2
Complete the following tasks to verify that a voice port is correctly configured for busyout monitoring:
Step 1 Shut down or bring up the monitored interface or interfaces, as required. This should cause the voice port to busy out. Monitored interfaces can be any of the following depending on your busyout configuration.
• Local interfaces—for busyout monitor interface
If the voice port is configured to monitor multiple local interfaces for out-of-service states.
busyout occurs only when all of the monitored interfaces go out of service. If a voice port is configured to monitor multiple local interfaces for the in-service state, busyout occurs when
any one monitored interface comes into service.• Remote interface—for busyout monitor probe
The voice port monitors a remote IP address for out-of-service states only.
Note Be sure that call fallback is configured on the local router and SAA responder is configured on the target router.
Step 2 Enter the show voice busyout command to display information about the busyout state.
The following is a sample display from the show voice busyout command for voice ports on a Cisco 7200:
Router# show voice busyoutVoice port busyout will be triggered by thefollowing network interfaces states3/0:0 busyout monitor FastEthernet0/01/6:0 probe 209.165.202.128 codec g711u icpif 25The following voice ports are in busyout stateYou can use the show voice busyout all command to display information about the busyout state.
The following is a sample display from the show voice busyout all command for DS-0 and PRI groups on a Cisco AS5300, Cisco AS5350 or Cisco AS5400 only:
Router# show voice busyout all
1 Current busyout for ds0-group and pri-group by voice-class busyout:T1(or E1) 0:DS0 Group 0:1 is in busyout state by voice-class busyout 12 Resource triggered busyout (for more info, check show call threshold status)The busyout isn't active right now3 Manual configured busyout for CAST1 0 manual busyout CAS time slots are:1, 2, 3, 4,T1 1 manual busyout CAS time slots are:T1 2 manual busyout CAS time slots are:T1 3 manual busyout CAS time slots are:
Configuration Examples
This section provides the following examples:
• Configuring a Soft Busyout Example
• Configuring a Hard Busyout Example
• Configuring a Voice Port to Monitor the Link to a Remote Interface Examples
• Configuring a Voice Class for Local Voice Busyout Examples
Configuring a Soft Busyout Example
The following example forces DS-0 time slots 1 through 12 on controller T1 0/1 on a Cisco 7200 series router into a soft busyout state:
Router(config)# controller t1 0/1Router(config-controller)# ds0 busyout 1-12 softRouter(config-controller)# exitConfiguring a Hard Busyout Example
The following example forces DS-0 time slot 3 on controller E1 on a Cisco 7200 series router into a soft busyout state:
Router(config)# controller e1 3/1Router(config-controller)# ds0 busyout 2 hardRouter(config-controller)# exitConfiguring a Voice Port to Monitor the Link to a Remote Interface Examples
The following example configures voice port 3/0:0 on a Cisco 7200 router to use an SAA probe with the default (G.711 ulaw) profile to probe the link to the remote interface with IP address 192.168.0.0, and to busyout the voice port if the link has packet loss and delay that exceeds the threshold values configured by the pstn fallback command:
Router(config)# voice-port 3/0:0Router(config-voiceport)# busyout monitor probe 198.168.0.0Router(config-voiceport)# exitThe following example configures voice port 3/0:0 on a Cisco 7200 to use an SAA probe with a G.711 ulaw profile to probe the link to the remote interface with IP address 198.169.101.0, and to busyout the voice port if the link has a packet loss of more than 50 percent and a packet delay of more than 25 milliseconds:
Router(config)# voice-port 3/0:0Router(config-voiceport)# busyout monitor probe 198.169.101.0 codec g711a loss 50 delay 25Router(config-voiceport)# exitConfiguring a Voice Class for Local Voice Busyout Examples
Cisco 2600 Series, Cisco 3600 Series, Cisco 7200 Series and MC3810
The following example configures busyout voice class 30, which initiates voice-port busyout whenever serial ports 0 and 1 both go out of service, and it applies voice class 30 to voice port 1/3:
Router(config)# voice class busyout 30
Router(config-class)#
busyout monitor serial 0Router(config-class)#
busyout monitor serial 1Router(config-class)# exit
Router(config)# voice-port 1/3Router(config-voiceport)# voice-class 30The following example configures busyout voice class 35, which initiates voice-port busyout whenever either serial port 0 or 1 is in service, and it applies voice class 35 to voice port 1/3:
Router(config)# voice class busyout 35
Router(config-class)#
busyout monitor serial 0 in-serviceRouter(config-class)#
busyout monitor serial 1 in-serviceRouter(config-class)# exit
Router(config)# voice-port 1/3Router(config-voiceport)# voice class 35The following example configures busyout voice class 40, which initiates voice-port busyout whenever an SAA probe sent to both of the two specified remote interfaces results in a link with an ICPIF delay/loss average of more than 15, and it applies voice class 40 to voice port 1/4:
Router(config)# voice class busyout 40
Router(config-class
)# busyout monitor probe 209.165.202.128 icpif 15Router(config-class
)# busyout monitor probe 209.165.202.129 icpif 15Router(config-class)# exit
Router(config)# voice-port 1/4Router(config-voiceport)# voice class 40The following example configures analog voice port 1/1 on a Cisco MC3810 to use an SAA probe with a G.711 ulaw profile to probe the link to the remote interface with IP address 209.165.202.128, and to busyout the voice port if the link has a packet loss of more than 50 percent and a packet delay of more than 25 milliseconds:
Router(config)# voice-port 1/1
Router(config-voiceport
)# busyout monitor probe 209.165.202.128 codec g711u loss 50 delay 25The following example configures voice port 1/0/1 on a Cisco 3600 series router to use an SAA probe with the default (G.711 alaw) profile to probe the link to the remote interface with IP address 209.165.202.128, and to busyout the voice port if the link has packet loss and delay that exceed the threshold values configured by the pstn fallback command:
Router(config)# voice-port 1/0/1
Router(config-voiceport)#
busyout monitor probe 209.165.202.128The following example configures busyout voice class 60, which configures multiple parameters for voice-port busyout, and it applies voice class 60 to voice ports 1:0.0 and 1:0.1 on a Cisco 3600 series router. The voice ports busyout under any one the following conditions:
•Serial ports 0/0 and 0/1 are both OOS
•Serial port 1/0 or 1/0 is in service
•The link loss exceeds 50 percent or the link delay exceeds 1 second on the links to both remote interfaces (IP addresses 209.165.202.128 and 209.165.202.129)
Router(config)# voice class busyout 60
Router(config-class)#
busyout monitor serial 0/0Router(config-class)#
busyout monitor serial 0/1Router(config-class)#
busyout monitor serial 1/0 in-serviceRouter(config-class)#
busyout monitor serial 1/1 in-serviceRouter(config-class
)# busyout monitor probe 209.165.202.128 loss 50 delay 1000Router(config-class
)# busyout monitor probe 209.165.202.129 loss 50 delay 1000Router(config-class)# exit
Router(config)# voice-port 1:0.0Router(config-voiceport)# voice class 60Router(config-voiceport)# exitRouter(config)# voice-port 1:0.1Router(config-voiceport)# voice class 60Router(config-voiceport)# exitCisco AS5300, Cisco AS5350 and Cisco AS5400
The following example configures a voice class with a tag number of 5. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to the interfaces 209.165.202.128/129 have an ICPIF delay/loss average of more than 15:
Router(config)# voice class busyout 5
Router(config-class)#
busyout monitor probe 209.165.202.128 icpif 15Router(config-class)#
busyout monitor probe 209.165.202.129 icpif 15Router(config-class)# exit
The following example configures a voice class with a tag number of 6. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to interface 209.165.202.128 have a packet loss of more than 50 percent and a packet delay of more than 25 milliseconds:
Router(config)# voice class busyout 6
Router(config-class)#
busyout monitor probe 209.165.202.128 codec g711u loss 50 delay 25Router(config-class)# exit
The following example assigns a voice class of 5 to a DS-0 group (with tag number 17) already configured on a T1 controller:
Router(config)# controller T1 1Router(config-controller
)# voice-class busyout 5 ds0-group 17Router(config-controller)# exit
The following example assigns a voice class of 6 to a PRI group already configured on an E1 controller:
Router(config)# controller E1 2Router(config-controller
)# voice-class busyout 6 pri-groupRouter(config-controller)# exit
Command Reference
This section documents new and modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.2 command reference publications.
New Commands
Modified Commands
clear interface
To effect a hard busy on DS-0s or the whole PRI interface after entering either of the isdn service commands, use the clear interface command in global configuration mode.
clear interface interface_name
no clear interface interface_name
Syntax Description
Defaults
Disabled
Command Modes
Global configuration
Command History
Examples
The following example clears the serial interface at slot 0 port 23:
Router(config)# clear interface serial0:23
Related Commands
isdn service b_channel
To take an individual B channel or an entire PRI interface out of service or sets it to a different channel service state that is passed in to the switch, use the isdn service command in interface configuration mode.
isdn service b_channel channel_range state state_value
no isdn service b_channel channel_range state state_value
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
This feature requires a configured B channel or PRI interface before the isdn service b_channel command can be entered.
Putting the B channel or PRI interface into the "Out of service" state effects a soft-busy.
Use the b_channel 0 phrase to set the entire PRI interface to the specified state value.
Use the show isdn service command to display the service states that were set by the isdn service command.
The digital subscriber line (DSL) is not affected by this command. The ISDN Non-Facility Associated Signaling (NFAS) feature can not be configured with this command.Refer to the isdn service dsl command for DSL service options.
Examples
The following example sets the entire PRI interface to the maintenance state:
Router(config-if)# isdn service b_channel 0 state 1
The following example puts B channel 11 out of service:
Router(config-if)# isdn service b_channel 11 state 2
Related Commands
busyout monitor
To place a voice port into the busyout monitor state, enter the busyout monitor command in voice-port configuration mode. To remove the busyout monitor state from the voice port, use the no form of this command.
busyout monitor {serial interface-number | ethernet interface-number | fastethernet interface-number} [in-service]
no busyout monitor {serial interface-number | ethernet interface-number | fastethernet interface-number} [in-service]
Syntax Description
Defaults
The voice port does not monitor any interfaces.
Command Modes
Voice-port configuration
Command History
Usage Guidelines
When you place a voice port in the busyout monitor state, the voice port monitors the specified interface and enters the busyout state when the interface is down.
This down state forces the rerouting of calls.
The command monitors only the up or down status of an interface—not end-to-end TCP/IP connectivity.
When an interface is operational, a busied-out voice port returns to its normal state.
This feature can monitor LAN, WAN, and virtual interfaces as well as subinterfaces.
The Cisco 2600 and 3600 series routers and the MC3810 multiservice concentrator support ATM interfaces. To monitor an ATM interface, enter ATM and the interface number.
A voice port can monitor multiple interfaces at the same time. To configure a voice port to monitor multiple interfaces, reenter the busyout monitor command for each additional interface to be monitored.
If you specify more than one monitored interface for a voice port, all the monitored interfaces must be down to trigger busyout on the voice port.
You can combine in-service and out-of-service monitoring on a voice port. The following rule describes the actions if monitored interfaces change state.
A voice port is busied out if either of the following occurs:
• Any interface monitored for coming into service comes up.
• All interfaces monitored for going out of service go down.
Examples
The following example configures voice port 2/1:1 on a Cisco 7200 router to busyout if Ethernet ports 0/0:0 and 1/0:1 both go out of service:
Router(config)# voice-port 2/1:1Router(config-voiceport)# busyout monitor ethernet 0/0:0Router(config-voiceport)# busyout monitor ethernet 1/0:1Router(config-voiceport)# exitThe following example configures voice port 2/1:1 on a Cisco 7200 router to busyout if Ethernet ports 0/0:0 and 1/0:1 both go out of service:
Router(config)# voice-port 2/1:1Router(config-voiceport)# busyout monitor fastethernet 0/0:0Router(config-voiceport)# busyout monitor fastethernet 1/0:1Router(config-voiceport)# exitThe following example configures digital voice 0/1:1 on a Cisco 7200 router to busyout if Ethernet ports 0/0 and 1/0 both go out of service:
Router(config)# voice-port 0/1:1Router(config-voiceport)# busyout monitor ethernet 0/1:1Router(config-voiceport)# busyout monitor serial 0/1:2Router(config-voiceport)# exitThe following example configures digital voice port 0/0:1 on a Cisco 7200 to busyout if Ethernet port 0/1:2 comes into service.
Router(config)# voice-port 0/0:1Router(config-voiceport)# busyout monitor ethernet 0/1:2 in-serviceRouter(config-voiceport)# exitThe following example configures voice port 2/1 on a Cisco 3600 series router to busyout if Ethernet ports 0/0 and 1/0 both go out of service:
Router(config)# voice-port 2/1
Router(config-voiceport)#
busyout monitor ethernet 0/0Router(config-voiceport)#
busyout monitor ethernet 1/0Router(config-voiceport)#
exitThe following example configures voice port 2/1 on a Cisco 3600 series router to busyout if Ethernet ports 0/0 and 1/0 both go out of service:
Router(config)# voice-port 2/1
Router(config-voiceport)#
busyout monitor fastethernet 0/0Router(config-voiceport)#
busyout monitor fastethernet 1/0Router(config-voiceport)#
exitThe following example configures digital voice port 0:6 on a Cisco MC3810 to busyout if both Ethernet port 0 and serial port 0 go out of service:
Router(config)# voice-port 0:6
Router(config-voiceport)#
busyout monitor ethernet 0Router(config-voiceport)#
busyout monitor serial 0Router(config-voiceport)#
The following example configures digital voice port 0:1 on a Cisco MC3810 to busyout if Ethernet port 0 goes into of service:
Router(config)# voice-port 0:1
Router(config-voiceport)#
busyout monitor ethernet 0 in-serviceRouter(config-voiceport)#
The following example configures a voice class with a tag number of 5 on a Cisco AS5300. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to the interfaces 209.165.202.128/129 have an ICPIF delay/loss average of more than 15.
Router(config)# voice class busyout 5
Router(config-voice-class)# busyout monitor probe 209.165.202.128 icpif 15Router(config-voice-class)# busyout monitor probe 209.165.202.129 icpif 15Router(config-voice-class)# exitRelated Commands
busyout monitor probe
To configure a voice port to enter the busyout state if an SAA probe signal returned from a remote, IP-addressable interface crosses a specified delay or loss threshold, use the busyout monitor probe command in voice-port configuration mode. Use the no form of this command to configure a voice port not to monitor SAA probe signals.
busyout monitor probe ip-address [codec codec-type | icpif number |
loss percent delay milliseconds]no busyout monitor probe ip-address
Syntax Description
Defaults
If this command is not entered, the voice port does not monitor SAA probe signals.
If this command is entered with no optional keywords or arguments, the default codec type is G.711 alaw and the default loss and delay thresholds are the threshold values configured with the pstn fallback command.
Command Modes
Cisco 2600 Series, Cisco 3600 Series, Cisco 7200 Series and Cisco MC3810
Voice-port configuration
Cisco AS5300
Voice-class configuration
Command History
Usage Guidelines
A voice port can monitor multiple interfaces at the same time. To configure a voice port or DS-0/PRI group to monitor multiple interfaces, reenter the command for each additional interface to be monitored.
This command is effective only if the call fallback function is enabled on this router and the SAA responder is enabled on the target router.
The SAA probe is transmitted periodically with a period determined by the PSTN fallback function.
Refer to the PSTN Fallback feature module for Cisco IOS Release 12.2(4)T for details of the PSTN fallback function and ICPIF values.
Lower thresholds of ICPIF, loss, and delay result in earlier busyout when the link deteriorates, thereby raising the voice minimum quality level. Higher thresholds prevent busyout until loss and delay are greater, allowing transmission of lower-quality voice.
Caution If thresholds are set too low, the link can alternate between in-service and out-of-service states, causing repeated interruptions of traffic.
Examples
The following example configures analog voice port 1/1 on a Cisco MC3810 to use an SAA probe with a G.711alaw profile to probe the link to two remote interfaces with IP addresses, and to busyout the voice port both links have a loss exceeding 25 percent or a packet delay of more than 1.5 seconds:
Router
(config)# voice-port 1/1Router
(config-voiceport
)# busyout monitor probe 209.165.202.128 codec g711a loss 25 delay 1500Router
(config-voiceport
)# busyout monitor probe 209.165.202.129 codec g711a loss 25 delay 1500The following example configures a voice class on a Cisco AS5300 with a tag number of 5. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to the interfaces 209.165.202.128/129 have an ICPIF delay/loss average of more than 15:
Router
(config)# voice class busyout 5Router(config-class)#
busyout monitor probe 209.165.202.128 icpif 15Router(config-class)#
busyout monitor probe 209.165.202.129 icpif 15Router
(config-class)# exitThe following example configures a voice class on a Cisco AS5300 with a tag number of 6. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to interface 209.165.202.128 have a packet loss of more than 50 percent and a packet delay of more than 25 milliseconds:
Router
(config)# voice class busyout 6Router(config-class)#
busyout monitor probe 209.165.202.128 codec g711u loss 50 delay 25Router
(config-class)# exitRelated Commands
busyout monitor serial
On the Cisco 2600 Series, Cisco 3600 Series, Cisco 7200 Series, and MC3810 only, to configure a voice port to monitor a serial interface for events that would trigger a voice-port busyout, use the
busyout monitor serial command in voice-port configuration mode. To configure a voice port not to monitor a serial interface for such events, use the no form of this commandbusyout monitor serial interface-number [in-service]
no busyout monitor serial interface-number
Syntax Description
Defaults
The voice port does not monitor any interfaces.
Command Modes
Voice-port configuration.
Command History
Usage Guidelines
A voice port can monitor multiple interfaces at the same time. To configure a voice port to monitor multiple interfaces, reenter the command for each additional interface to be monitored.
You can combine in-service and out-of-service monitoring on a voice port. The following rule describes the actions if monitored interfaces change state:
A voice port is busied out if:
•Any interface monitored for coming into service comes up
•All interfaces monitored for going out of service go down
Examples
The following example configures analog voice port 1/1 on a Cisco MC3810 to busyout if serial ports 1 and 0:0 both go out of service:
Router
(config)# voice-port 1/1Router(config-voiceport)#
busyout monitor serial 0:0Router(config-voiceport)#
busyout monitor serial 1Router(config-voiceport)#
The following example configures analog voice port 1/2 on a Cisco MC3810 to busyout if serial port 0 or 1 goes into service:
Router
(config)# voice-port 1/2Router(config-voiceport)#
busyout monitor serial 0 in-serviceRouter(config-voiceport)#
busyout monitor serial 1 in-serviceRouter(config-voiceport)#
The following example configures digital voice port 1/2:2 on a Cisco 3600 series router to busyout if serial ports 0/0, 0/1, 1/0 and 1/1 all go out of service:
Router
(config)# voice-port 1/2:2Router(config-voiceport)#
busyout monitor serial 0/0Router(config-voiceport)#
busyout monitor serial 0/1Router(config-voiceport)#
busyout monitor serial 1/0Router(config-voiceport)#
busyout monitor serial 1/1Router(config-voiceport)#
The following example configures digital voice port 0:6 on a Cisco MC3810 to busyout if both Ethernet port 0 and serial port 0 go out of service:
Router
(config)# voice-port 0:6Router(config-voiceport)#
busyout monitor ethernet 0Router(config-voiceport)#
busyout monitor serial 0Router(config-voiceport)#
The following example configures analog voice port 1/1:0 on a Cisco 7200 to busyout if serial ports 1/0:0 and 0/1:1 both go out of service:
Router(config)# voice-port 1/1:0Router(config-voiceport)# busyout monitor serial 1/0:0Router(config-voiceport)# busyout monitor serial 0/1:1The following example configures voice port 1/2:2 on a Cisco 7200 to busyout if serial port 0/1:0 or 1/1:1 comes into service:
Router(config)# voice-port 1/2:2Router(config-voiceport)# busyout monitor serial 0/1:0 in-serviceRouter(config-voiceport)# busyout monitor serial 1/1:1 in-serviceThe following example configures digital voice port 1/2:2 on a Cisco 7200 router to busyout if serial ports 0/1:1, 0/1:1, 1/1:1 and 1/1:1 all go out of service:
Router(config)# voice-port 1/2:2Router(config-voiceport)# busyout monitor serial 0/1:1Router(config-voiceport)# busyout monitor serial 0/1:1Router(config-voiceport)# busyout monitor serial 1/1:1Router(config-voiceport)# busyout monitor serial 1/1:1The following example configures digital voice port 0/1:6 on a Cisco 7200 router to busyout if both Ethernet port 0/0:1 and serial port 0/1:1 go out of service:
Router(config)# voice-port 0/1:6Router(config-voiceport)# busyout monitor ethernet 0/0:1Router(config-voiceport)# busyout monitor serial 0/1:1Related Commands
ds0 busyout
To force a DS-0 time slot on a controller into the busyout state, use the ds0 busyout command in controller configuration mode. Use the no form of this command to remove the DS-0 time slot from the busyout state.
ds0 busyout ds0-timeslot [soft | hard]
no ds0 busyout ds0-timeslot
Syntax Description
ds0-timeslot
DS-0 time slot to be forced into the busyout state. The range is 1 to 24 time slots in any combination.
soft
(Optional) Enables soft busyout.
hard
(Optional) Enables hard busyout.
Defaults
DS-0 time slots are not in busyout state.
Command Modes
Controller configuration
Command History
Usage Guidelines
This command affects only DS-0 time slots that are configured into a DS-0 group and function as part of a digital voice port. If multiple DS-0 groups are configured on a controller, you can busy out any combination of DS-0 time slots, as long as each DS-0 time slot to be busied out is part of a DS-0 group.
If a DS-0 time slot is in the busyout state, only the no ds0 busyout command can restore the DS-0 time slot to service.
To avoid conflicting CLI commands, do not use the ds0 busyout command and the busyout forced command on the same controller.
All the channels which are manually busied out are NOT automatically unbusied. The manual unbusyout command is needed to unbusy these channels.
Examples
The following example forces DS-0 time slot 6 on controller T1 0 into the hard busyout state:
Router
(config)# controller t1 0Router
(config-controller)# ds0 busyout 6 hardThe following example forces DS-0 time slots 1, 3, 4, 5, 6, and 24 on controller E1 1 into the soft (default) busyout state:
Router
(config)# controller e1 1Router
(config-controller)# ds0 busyout 1,3-6,24The following example forces DS-0 time slot 6 on controller T1 0/1:1 into the hard busyout state:
Router
(config)# controller t1 0/1:1Router
(config-controller)# ds0 busyout 6 hardThe following example forces DS-0 time slots 1, 3, 4, 5, 6, and 24 on controller E1 1/1:0 into the soft (default) busyout state:
Router
(config)# controller e1 1/1:0Router
(config-controller)# ds0 busyout 1,3-6,24Related Commands
Command Descriptionshow running configuration
Use this command to determine which DS-0 time slots have been forced into the busyout state.
isdn service dsl
To take an individual B channel or an entire PRI interface out of service or set it to a different channel service state that is passed in to the switch, use the isdn service command in interface configuration mode.
isdn service dsl dsl_value b_channel channel_range state state_value
no isdn service dsl dsl_value b_channel channel_range state state_value
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
This feature requires a configured B channel or PRI interface before the isdn service command can be entered.
This command is used to configure the ISDN Non-Facility Associated Signaling (NFAS) feature on Cisco routers.
Putting the B channel or PRI interface into the "Out of service" state effects a soft-busy.
Use the b_channel 0 phrase to set the entire PRI interface to the specified state value.
Use the show isdn status command to display the digital subscriber line (DSL) value. Use the show isdn service command to display the service states that were set by the isdn service command.
Examples
The following example sets the entire PRI interface to maintenance state; the digital signal line (DSL) value was displayed and then used in the command:
Router(config-if)# isdn service dsl 3 b_channel 0 state 1
The following example puts B channel 11 out of service; the DSL value was displayed and then used in the command:
Router(config-if)# isdn service dsl 3 b_channel 11 state 2
Related Commands
show voice busyout (all)
To display voice busyout stats, use the show voice busyout EXEC command. On the Cisco AS5300, Cisco AS5350, and Cisco AS5400 only, to display all three types of voice busyout stats (AVBO, resource-based busyout, and manual busyout on DS-0), use the show voice busyout all EXEC command.
show voice busyout
show voice busyout all
Syntax Description
Defaults
None
Command Modes
EXEC
Command History
Usage Guidelines
The show voice busyout all command is only available for the Cisco AS5300, Cisco AS5350, and Cisco AS5400. The command displays all three types of busyout (advanced voice busyout, resource-based busyout, and manual busyout on DS-0).
Examples
The following is a sample display from the show voice busyout command on a Cisco 3640 router:
Router
# show voice busyoutVoice port busyout will be triggered by thefollowing network interfaces states1/0:0 probe 11.0.0.2 codec g711ulaw1/0:1 probe 11.0.0.2 codec g711ulaw1/0:2 probe 11.0.0.2 codec g711ulaw1/0:3 probe 11.0.0.2 codec g711ulaw1/0:4 probe 11.0.0.2 codec g711ulaw1/0:5 probe 11.0.0.2 codec g711ulaw1/0:6 probe 11.0.0.2 codec g711ulaw1/0:7 probe 11.0.0.2 codec g711ulaw1/0:8 probe 11.0.0.2 codec g711ulaw1/0:9 probe 11.0.0.2 codec g711ulaw1/0:10 probe 11.0.0.2 codec g711ulaw1/0:11 probe 11.0.0.2 codec g711ulaw1/0:12 probe 11.0.0.2 codec g711ulaw1/0:13 probe 11.0.0.2 codec g711ulaw1/0:14 probe 11.0.0.2 codec g711ulaw1/0:15 probe 11.0.0.2 codec g711ulaw1/0:16 probe 11.0.0.2 codec g711ulaw1/0:17 probe 11.0.0.2 codec g711ulaw1/0:18 probe 11.0.0.2 codec g711ulaw1/0:19 probe 11.0.0.2 codec g711ulaw1/0:20 probe 11.0.0.2 codec g711ulaw1/0:21 probe 11.0.0.2 codec g711ulaw1/0:22 probe 11.0.0.2 codec g711ulaw1/0:23 probe 11.0.0.2 codec g711ulaw1/1:0 probe 11.0.0.2 codec g711ulaw1/1:1 probe 11.0.0.2 codec g711ulaw1/1:2 probe 11.0.0.2 codec g711ulaw1/1:3 probe 11.0.0.2 codec g711ulaw1/1:4 probe 11.0.0.2 codec g711ulaw1/1:5 probe 11.0.0.2 codec g711ulaw1/1:6 probe 11.0.0.2 codec g711ulaw1/1:7 probe 11.0.0.2 codec g711ulaw1/1:8 probe 11.0.0.2 codec g711ulaw1/1:9 probe 11.0.0.2 codec g711ulaw1/1:10 probe 11.0.0.2 codec g711ulaw1/1:11 probe 11.0.0.2 codec g711ulaw1/1:12 probe 11.0.0.2 codec g711ulaw1/1:13 probe 11.0.0.2 codec g711ulaw1/1:14 probe 11.0.0.2 codec g711ulaw1/1:15 probe 11.0.0.2 codec g711ulaw1/1:16 probe 11.0.0.2 codec g711ulaw1/1:17 probe 11.0.0.2 codec g711ulaw1/1:18 probe 11.0.0.2 codec g711ulaw1/1:19 probe 11.0.0.2 codec g711ulaw1/1:20 probe 11.0.0.2 codec g711ulaw1/1:21 probe 11.0.0.2 codec g711ulaw1/1:22 probe 11.0.0.2 codec g711ulaw1/1:23 probe 11.0.0.2 codec g711ulawThe following is a sample display from the show voice busyout all command for DS-0 and PRI groups on a Cisco AS5300:
Router
# show voice busyout all1 Current busyout for ds0-group and pri-group by voice-class busyout:T1(or E1) 0:DS0 Group 0:1 is in busyout state by voice-class busyout 12 Resource triggered busyout (for more info, check show call threshold status)The busyout isn't active right now3 Manual configured busyout for CAST1 0 manual busyout CAS time slots are:1, 2, 3, 4,T1 1 manual busyout CAS time slots are:T1 2 manual busyout CAS time slots are:T1 3 manual busyout CAS time slots are:Related Commands
Command Descriptionvoice class busyout
Creates a voice class for local voice busyout functions.
voice-class busyout
Assigns a voice class to a DS-0/PRI group.
voice class busyout
To create a voice class for local voice busyout functions, use the voice class busyout command in global configuration mode. Enter the no form of this command to delete the voice class.
voice class busyout tag
no voice class busyout tag
Syntax Description
tag
A unique identification number assigned to one voice class. The range is 1 to 10,000. The tag number must be unique to the router.
Defaults
No voice class is configured for busyout functions.
Command Modes
Global configuration
Command History
Usage Guidelines
You can apply a busyout voice class to multiple voice ports.
You can assign only one busyout voice class to a voice port. If a second busyout voice class is assigned to a voice port, the second voice class replaces the one previously assigned
If you assign a busyout voice class to a voice port, you may not assign separate busyout commands directly to the voice port, such as busyout monitor serial, busyout monitor ethernet, or
busyout monitor probe.Examples
The following example configures busyout voice class 20, in which the connections to two remote interfaces are monitored by an SAA probe with a G.711ulaw profile, and voice ports are busied out whenever both links have a packet loss exceeding 10 percent and packet delay time exceeding 2 seconds:
Router
(config)# voice class busyout 20Router(config-class)#
busyout monitor probe 209.165.202.128 g711u loss 10 delay 2000Router(config-class)#
busyout monitor probe 209.165.202.129 g711u loss 10 delay 2000Router(config-class)#
The following example configures busyout voice class 30, in which voice ports are busied out when serial ports 0/0, 1/0, 2/0, and 3/0 go out of service.
Router
(config)# voice class busyout 30Router(config-class)#
busyout monitor serial 0/0Router(config-class)#
busyout monitor serial 1/0Router(config-class)#
busyout monitor serial 2/0Router(config-class)#
busyout monitor serial 3/0Router(config-class)#
Cisco AS5300, Cisco AS5350, and Cisco AS5400
The following example configures a voice class with a tag number of 5. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to the interfaces 209.165.202.128/129 have an ICPIF delay/loss average of more than 15:
Router
(config)# voice class busyout 5Router(config-class)#
busyout monitor probe 209.165.202.128 icpif 15Router(config-class)#
busyout monitor probe 209.165.202.129 icpif 15Router
(config-class)# exitThe following example configures a voice class with a tag number of 6. If this class is assigned to a DS-0 or PRI group, the group will busyout if the SAA probes sent to interface 209.165.202.128 have a packet loss of more than 50 percent and a packet delay of more than 25 milliseconds:
Router
(config)# voice class busyout 6Router(config-class)#
busyout monitor probe 209.165.202.128 codec g711u loss 50 delay 25Router
(config-class)# exitRelated Commands
voice-class busyout
On the Cisco AS5300, Cisco AS5350 and Cisco AS5400 only, to assign a voice class to a DS-0/PRI group, use the voice-class busyout command in controller configuration mode. Enter the no form of this command to delete the voice class.
voice-class busyout voice-class-tag {ds0-group group-number | pri-group [shut-if]}
no voice-class busyout voice-class-tag
Syntax Description
Defaults
No voice class is configured for busyout functions.
Command Modes
Controller configuration.
Command History
Usage Guidelines
You can assign only one busyout voice class to a group. If a second busyout voice class is assigned to a DS-0/PRI group, the second voice class replaces the one previously assigned.
You should assign the same busyout voice class to multiple DS-0 groups.
The following example assigns a voice class of 5 to a DS-0 group (with tag number 17) already configured on a T1 controller:
Router
(config)# controller T1 1Router
(config-controller
)# voice-class busyout 5 ds0-group 17Router
(config-controller)# exitThe following example assigns a voice class of 6 to a PRI group already configured on an E1 controller:
Router
(config)# controller E1 2Router
(config-controller
)# voice-class busyout 6 pri-groupRouter
(config-controller)# exitRelated Commands
Glossary
AVBO—Advanced Voice Busy Out.
CLI—Command line interface.
Codec—Coder-Decoder. An integrated circuit device that typically uses pulse code modulation to transform analog signals into a digital bit stream and digital signals back into analog signals. In Voice over IP, Voice over Frame Relay, and Voice over ATM, a DSP software algorithm used to compress/decompress speech or audio signals.
DLCI—data-link connection identifier.
Dial peer—An addressable call endpoint that contains configuration information including voice protocol, a CODEC type, and a telephone number associated with the call endpoint. There are five kinds of dial peers: POTS, VoIP, VoFR, VoATM, and VoHDLC.
DS-0—digital signal level 0. Framing specification used in transmitting digital signals over a single channel at 64-kbps on a T1 facility.
DSP—Digital Signaling Processor.
DTMF—dual tone multifrequency. Uses two simultaneous voice-band tones for dial such as touch tone.
DTMF relay—Enables the generation of FRF.11 Annex A frames for a VoFR dial peer. The DSP generates Annex A frames instead of passing a DTMF tone through the network as a voice sample.
Dynamic switched call—A telephone call dynamically established across a packet data network based on a dialed telephone number. In the case of VoFR, a Cisco proprietary session protocol similar to Q.931 is used to achieve call switching and negotiation between calling endpoints. The proprietary session protocol runs over FRF.11-compliant subchannels.
E&M—Stands for recEive and transMit (or Ear and Mouth). E&M is a trunking arrangement generally used for two-way switch-to-switch or switch-to-network connections. Cisco's analog E&M interface is an RJ-48 connector that allows connections to PBX trunk lines (tie lines). E&M is also available on E1 and T1 digital interfaces.
E1—European equivalent of T1. 32-64kbps channels include 1-channel for framing and 1-channel for D-channel information at a 2.048 Mhz clock rate.
FRF—Frame Relay Forum. An association of corporate members consisting of vendors, carriers, users, and consultants committed to implementing Frame Relay in accordance with national and international standards. See http://www.frforum.com.
FXO—Foreign Exchange Office. An FXO interface connects to the Public Switched Telephone Network's (PSTN) central office and is the interface offered on a standard telephone. Cisco's FXO interface is an RJ-11 connector that allows an analog connection to be directed to the PSTN's central office or to a station interface on a PBX.
FXS—Foreign Exchange Station. An FXS interface connects directly to a standard telephone and supplies ring, voltage, and dial tone. Cisco's FXS interface is an RJ-11 connector that allows connections to basic telephone service equipment, keysets, and PBXs.
ICPIF—Calculated Planning Impairment Factor. Calculated and used as per the ITU G.113 specification.
LLQ—low latency queuing. LLQ brings strict priority queueing to Class-Based Weighted Fair Queueing (CBWFQ). Strict priority queueing allows delay-sensitive data such as voice to be dequeued and sent first (before packets in other queues are dequeued), giving delay-sensitive data preferential treatment over other traffic.
LVBO—Local Voice Busy Out.
MD5—Message Digest 5. Algorithm used for message authentication in SNMP v.2. MD5 verifies the integrity of the communication, authenticates the origin, and checks for timeliness.
MEL CAS—Mercury Exchange Limited (MEL) Channel Associated Signaling. A voice signaling protocol used primarily in the United Kingdom.
OOS—Out of Service state of the call or trunk.
PBX—Private Branch Exchange. A privately owned central switching office.
Permanent calls—Permanent calls are private line calls used for fixed point-to-point calls, connections between PBXs (E&M to E&M), or for remote telephone extensions (FXO to FXS).
POTS—Plain old telephone service. Basic telephone service supplying standard single line telephones, telephone lines, and access to the PSTN.
POTS dial peer—Dial peer connected by a traditional telephony network. POTS peers point to a particular voice port on a voice network device.
PRI—Primary Rate Interface. ISDN interface to primary rate access. Primary rate access consists of a single 64-Kbps D channel plus 23 (T1) or 30 (E1) B channels for voice or data.
PSTN—Public Switched Telephone Network. PSTN refers to the local telephone company.
RAI—Resource Availability Indicator.
RTP—Routing Table Protocol.
SAA—Service Assurance Agent. Formerly known as Response Time Reporter (RTR). Works alongside TCP to carry streaming data over the network. RTP uses packet headers that contain sequencing information, time stamps required to time the output (for example, display of frames) and synchronize different data streams (for example, audio and video), and information on the packet's "payload" (for example, MPEG versus H.261 encoding). This payload descriptor allows RTP to support multiple compression types.
Switched calls—Switched calls are normal telephone calls when a user picks up a phone, hears a dial tone and enters the destination phone number to reach the other phone. Switched calls can also be private line auto-ringdown (PLAR) calls, or tie-line calls for fixed point-to-point connections.
T1—Digital WAN carrier facility. T1 transmits DS-1-formatted data at 1.544 Mbps through the telephone-switching network by using AMI or B8ZS coding.
TCP—Transmission Control Protocol. Connection-oriented transport layer protocol that provides reliable full-duplex data transmission.
Trunk—Service that allows quasi-transparent connections between two PBXs, a PBX and a local extension, or some other combination of telephony interfaces with signaling passed transparently through the packet data network.
Voice over Frame Relay—Voice over Frame Relay enables a router to carry voice traffic (for example, telephone calls and faxes over a Frame Relay network. When sending voice traffic over Frame Relay, the voice traffic is segmented and encapsulated for transit across the Frame Relay network by using FRF.12 encapsulation.
Voice over IP—Voice over IP enables a router to carry voice traffic, for example, telephone calls and faxes) over an IP network. In Voice over IP, the DSP segments the voice signal into frames, which are then coupled in groups of two and stored in voice packets that are transported by using IP in compliance with ITU-T specification H.323.
Note For a list of other internetworking terms, see Internetworking Terms and Acronyms, available on the Documentation CD-ROM and Cisco.com at the following URL: http://www.cisco.com/univercd/cc/td/doc/cisintwk/ita/index.htm.