|
|
This document describes how to configure the Busyout Monitor feature on Cisco 2600 and 3600 series routers and includes the following sections:
The Busyout Monitor feature is one aspect of Call Admission Control (CAC) that allows network administrators to use both a data network and the public switched telephone network (PSTN) to provide the best possible quality for Voice over IP (VoIP) calls. Although voice calls are routed across the data network whenever possible to take advantage of the cost savings provided by integrated applications, the Busyout Monitor allows network administrators to provide voice services through the PSTN in the event of a network interface failure.
If a locally connected LAN or WAN interface on a VoIP gateway fails, it busies out voice ports. This means that a connected private-branch exchange (PBX) or key system reroutes the call through the local PSTN.
The Busyout Monitor CAC feature provides the following benefits:
Busyout Monitor monitors only locally connected LAN/WAN interfaces and does not monitor the status of remote devices. The feature cannot determine the status of the end-to-end path.
This feature is supported on the following platforms:
The Busyout Monitor feature does not support any standards, MIBs, or RFCs.
The Busyout Monitor feature requires the following software, hardware, and configuration:
Voice, Video, and Home Applications Configuration Guide and Voice, Video, and Home Applications Command Reference for Cisco IOS Release 12.0 provide information about setting up voice networks.
The Busyout Monitor feature is configured on a voice port used for VoIP applications.
Follow these steps to set up voice ports to support local and remote stations. Not all possible commands are shown here. See Voice, Video, and Home Applications Configuration Guide and Voice, Video, and Home Applications Command Reference for Cisco IOS Release 12.0.
| Step | Command | Purpose | ||
|---|---|---|---|---|
| Router# configure terminal | Enter global configuration mode. | ||
| Router(config)# voice-port slot/port:ds0-group-no | Note This voice-port command syntax does not apply to analog voice network modules and voice interface cards. The latter are specified by using slot/subunit/port, designating the router slot for the voice network module, the location of the voice interface card in the network module, and the port on the voice interface card.
Enter voice-port configuration mode. slot is the router location where the voice module is installed. Valid entries are from 0 to 5. port indicates the voice interface card location. Valid entries are 0 or 1. When you are configuring a digital voice card, each defined DS0 group number is represented on a separate voice port, so that you can define individual DS0s on the card. For more information about DS0 groups, see Configuring Digital T1 Packet Voice Trunk Network Modules on Cisco 2600 and 3600 Series Routers. | ||
| Router(config-voice-port)# busyout monitor interface | (Optional) This command allows you to specify a LAN or WAN interface that will be monitored, and, when it is down, trigger a busyout (offhook) state on the voice port. This allows rerouting of calls. For example, if you specify Serial 1/0 as the interface and number, the voice port sends a busyout signal when that interface is down. You can issue the command repeatedly to specify as many interfaces, virtual interfaces, and subinterfaces as are required for a voice port. For example, if you issue the command three times so that three interfaces are monitored, the voice port only goes into busyout state when all three interfaces are down. When any one of the interfaces is operational, the busyout state is removed. | ||
| Router(config-voice-port)# comfort-noise | (Optional) This parameter is enabled by default. It creates subtle background noise to fill silent gaps during calls when VAD is enabled on voice dial peers. If comfort noise is not generated, the silence can be unsettling to callers. | ||
| Router(config-voice-port)# echo-cancel enable | (Optional) This setting is enabled by default. Echo cancellation adds to the quality of voice transmissions by adjusting the echo that occurs on the interface due to impedance mismatches. Some echo is reassuring; echo over 25 milliseconds can cause problems. | ||
| Router(config-voice-port)# echo-cancel coverage {16 | 24 | (Optional) This command adjusts the echo canceller by the specified number of milliseconds; the default is 16. | ||
| Router(config-voice-port)# timeouts interdigit seconds | (Optional) This command sets the number of seconds the system waits---after the caller has input the initial digit---for a subsequent digit of the dialed string. If the timeout ends before the destination is identified, a tone sounds and the call ends. The default value is 10 seconds, and the timeout can be set from 0 to 120 seconds. Note Changes to the default for this command normally are not required. Other timing settings may also be needed. For more information, see the Cisco IOS Release 12.0 Voice, Video, and Home Applications Configuration Guide. | ||
| Router(config-voice-port)# exit | Exit voice-port configuration mode. |
This example shows the Busyout Monitor feature used on a digital voice interface. The feature instructs the voice gateway to busy out the voice port (all channels defined in the corresponding DS0 Group) if serial 2/1 fails. When the specified LAN/WAN interface becomes available again, the voice port is put back into service for handling VoIP calls.
hostname RTR-A ! voice-card 1 ! controller T1 1/0 framing esf linecoding b8zs clock source line ds0-group 1 timeslots 1-24 type e&m-wink ! voice-port 1/0:1 busyout monitor interface serial 2/1 ! interface serial 2/1 encapsulation ppp bandwidth 1544 ip address 10.168.100.1 255.255.255.0 ! interface ethernet 0/0 ip address 10.168.102.1 255.255.255.0 ! dial-peer voice 1 voip destination-pattern 5.... codec g711u dtmf-relay h245-alphanumeric session target ipv4:10.168.100.2 ! dial-peer voice 2 pots destination-pattern 4.... prefix 4 port 1/0:1 | hostname RTR-B ! voice-card 1 ! controller T1 1/0 framing esf linecoding b8zs clock source line ds0-group 1 timeslots 1-24 type e&m-wink ! voice-port 1/0:1 busyout monitor interface serial 2/0 ! interface serial 2/0 encapsulation ppp bandwidth 1544 ip address 10.168.100.2 255.255.255.0 ! interface ethernet 0/0 ip address 10.168.101.1 255.255.255.0 ! dial-peer voice 1 voip destination-pattern 4.... codec g711u dtmf-relay h245-alphanumeric session target ipv4:10.168.100.1 ! dial-peer voice 2 pots destination-pattern 5.... prefix 5 port 1/0:1 |
This section documents a new command. All other commands used with this feature are documented in the Cisco IOS Release 12.0 command references.
To place a voice port into a busyout monitor state, use the busyout-monitor interface voice-port configuration command. To remove the busyout monitor state on the voice port, use the no form of this command.
busyout-monitor interface interface number
interface | The name of the associated interface or subinterface that will be monitored to trigger a voice-port busyout, for example serial, atm, or ethernet. |
number | The slot and port position of the interface or subinterface, for example, 0/1, 1/1.0, and so on. |
The voice port is not in busyout monitor state.
Voice-port configuration
| Release | Modification |
|---|---|
12.0(3)T | This command was introduced for the Cisco MC3810. |
12.0(5)XK and 12.0(7)T | The command was modified for the Cisco 2600 and 3600 series. |
When you place a voice port in a busyout monitor state, the voice port monitors the specified interface and enters the busyout state when the interface is down. This forces rerouting of calls when an interface is down.
If you specify more than one monitored interface for a voice port, all the monitored interfaces must be down in order to trigger a busyout on the voice port.
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, virtual interfaces, and subinterfaces.
The following example configures the voice port to monitor two serial interfaces and an Ethernet interface. When all these interfaces are down, the voice port is busied out. When at least one interface is operating, the voice port is put back into a normal state.
voice-port 3/0:0 busyout monitor interface Ethernet0/0 busyout monitor interface Serial1/0 busyout monitor interface Serial2/0
CAC---call admission control. The ability to provide packet voice services based on the status of the data network.
PBX---private branch exchange. Digital or analog telephone switchboard located on the subscriber premises and used to connect private and public telephone networks.
PSTN---Public Switched Telephone Network. General term referring to the variety of telephone networks and services in place worldwide.
Posted: Tue Jan 25 15:29:20 PST 2000
Copyright 1989 - 2000©Cisco Systems Inc.