- IP SLAs Overview
- Configuring Auto IP SLAs in IP SLAs Engine 3.0
- Configuring IP SLA - Percentile Support for Filtering Outliers
- Configuring IP SLAs Video Operations
- Configuring IP SLAs UDP Jitter Operations
- IP SLA - Support for OnDemand UDP Probes
- Configuring IP SLAs UDP Jitter Operations for VoIP
- IP SLAs Multicast Support
- Configuring IP SLAs LSP Health Monitor Operations
- Configuring IP SLAs for Metro-Ethernet
- Configuring Cisco IP SLAs ICMP Jitter Operations
- Configuring RTP-Based VoIP Operations
- Configuring VoIP Gatekeeper Registration Delay Operations
- Configuring VoIP Call Setup Monitoring
- Configuring IP SLAs UDP Echo Operations
- Configuring IP SLAs HTTP Operations
- Configuring IP SLAs TCP Connect Operations
- Configuring IP SLAs ICMP Echo Operations
- Configuring IP SLAs ICMP Path Echo Operations
- Configuring IP SLAs ICMP Path Jitter Operations
- Configuring IP SLAs FTP Operations
- Configuring IP SLAs DNS Operations
- Configuring IP SLAs DHCP Operations
- Configuring IP SLAs DLSw+ Operations
- Configuring an IP SLAs Multioperation Scheduler
- Configuring Proactive Threshold Monitoring for IP SLAs Operations
- IP SLAs TWAMP Responder
- Finding Feature Information
- Prerequisites for IP SLAs RTP-Based VoIP Operations
- Restrictions for IP SLAs RTP-Based VoIP Operations
- Information About IP SLAs RTP-Based VoIP Operations
- How to Configure IP SLAs RTP-Based VoIP Operations
Configuring RTP-Based VoIP Operations
This module describes how to configure an IP Service Level Agreements (SLAs) Real-Time Transport Protocol (RTP)-based Voice over IP (VoIP) Operation feature to set up and schedule a test call for using Voice gateway digital signal processors (DSPs) to gather network performance-related statistics for the call. Available statistical measurements for VoIP networks include jitter, frame loss, Mean Opinion Score for Conversational Quality (MOS-CQ), and Mean Opinion Score for Listening Quality (MOS-LQ).
- Finding Feature Information
- Prerequisites for IP SLAs RTP-Based VoIP Operations
- Restrictions for IP SLAs RTP-Based VoIP Operations
- Information About IP SLAs RTP-Based VoIP Operations
- How to Configure IP SLAs RTP-Based VoIP Operations
- Configuration Examples for IP SLAs RTP-Based VoIP Operations
- Additional References
- Feature Information for IP SLAs RTP-Based VoIP Operations
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for IP SLAs RTP-Based VoIP Operations
Both the source and destination routers must be running Cisco IOS Release 12.4(4)T or later releases.
Both the source and destination routers must be running a Cisco IOS image with the Cisco IOS IP Voice or higher grade feature package.
The source router must have a network module with a c5510 or c549 DSP. The destination router need not have a network module with a DSP.
The IP SLAs Responder must be enabled on the destination gateway.
Restrictions for IP SLAs RTP-Based VoIP Operations
The IP SLAs RTP-based VoIP operation gathers statistical information only from the DSP of the source router.
For source-to-destination measurements, the RTP-based VoIP operation does not obtain statistical information from DSPs.
Depending on the type of DSP, the statistics measured by the IP SLAs RTP-based VoIP operation will vary. For more information, see the “Statistics Measured by the IP SLAs RTP-Based VoIP Operation” section.
The voice port used by the IP SLAs RTP-based VoIP operation will not be available for other calls.
Information About IP SLAs RTP-Based VoIP Operations
- Benefits of the IP SLAs RTP-Based VoIP Operation
- Statistics Measured by the IP SLAs RTP-Based VoIP Operation
Benefits of the IP SLAs RTP-Based VoIP Operation
The IP SLAs RTP-Based VoIP Operation feature provides the following key benefits:
End-to-end performance measurements using DSPs for determining voice quality in VoIP networks.
Proactive threshold violation monitoring through Simple Network Management Protocol (SNMP) trap notifications and syslog messages.
Statistics Measured by the IP SLAs RTP-Based VoIP Operation
The IP SLAs RTP-based VoIP operation provides an enhanced capability to measure voice quality using DSP-based calculations to determine MOS scores. For customer scenarios where the destination gateway does not have DSP hardware, statistical information is gathered only from the DSP of the source gateway. In this case, the RTP data stream is looped back from the destination to the source gateway.
The statistics gathered by the IP SLAs RTP-based VoIP operation will vary depending on the type of DSP module (see the tables below).
Statistics |
Description |
---|---|
Interarrival jitter (destination-to-source and source-to-destination) |
Interarrival jitter is the mean deviation (smoothed absolute value) of the difference in packet spacing for a pair of packets. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. For more information about interarrival jitter, see RFC 3550 (RTP: A Transport Protocol for Real-Time Applications ). |
Estimated R factor (destination-to-source and source-to-destination) |
Estimated transmission rating factor R. This value is based on one-way transmission delay and standard default values. No values are obtained from the DSP to calculate the estimated transmission rating factor R. For more information about the estimated R factor, see International Telecommunication Union Telecommunication Standardization Sector (ITU-T) Recommendation G.107 (The E-model, a computational model for use in transmission planning ). |
MOS-CQ (destination-to-source and source-to-destination) |
Mean Opinion Score for Conversational Quality. This value is obtained by conversion of the estimated R factor to Mean Opinion Score (MOS) using ITU-T Recommendation G.107 conversion tables. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. |
Round-trip time (RTT) latency |
Round-trip time latency for an RTP packet to travel from the source to the destination and back to the source. |
Packet loss (destination-to-source and source-to-destination) |
Number of packets lost. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. |
Packets missing in action (source-to-destination) |
Number of missing packets. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. |
One-way latency (destination-to-source and source-to-destination) |
Average, minimum, and maximum latency values. These values are measured by sending RTP packets to IP SLAs Responder. The RTP data stream is then looped back from the destination to the source gateway. |
Statistics |
Description |
---|---|
Interarrival jitter (destination-to-source and source-to-destination) |
Interarrival jitter is the mean deviation (smoothed absolute value) of the difference in packet spacing for a pair of packets. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. For more information on how this value is calculated, see RFC 1889 (RTP: A Transport Protocol for Real-Time Applications ). |
Estimated R factor (destination-to-source and source-to-destination) |
Estimated transmission rating factor R. This value is based on one-way transmission delay and standard default values, as well as values obtained from the DSP. For more information about how to calculate the estimated R factor, see International Telecommunication Union Telecommunication Standardization Sector (ITU-T) Recommendation G.107 (The E-model, a computational model for use in transmission planning ). |
MOS-CQ (destination-to-source and source-to-destination) |
Mean Opinion Score for Conversational Quality. This value is obtained by conversion of the estimated R factor to Mean Opinion Score (MOS) using ITU-T Recommendation G.107 conversion tables. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. |
Round-trip time (RTT) latency |
Round-trip time latency for an RTP packet to travel from the source to the destination and back to the source. |
Packet loss (destination-to-source and source-to-destination) |
Number of packets lost. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. |
Packets missing in action (source-to-destination) |
Number of missing packets. The source-to-destination value is measured by sending RTP packets to the IP SLAs Responder. No values are obtained from the DSP for this measurement. |
One-way latency (destination-to-source and source-to-destination) |
Average, minimum, and maximum latency values. These values are measured by sending RTP packets to IP SLAs Responder. The RTP data stream is then looped back from the destination to the source gateway. |
Frame loss (destination-to-source) |
Number of DSP frame loss events. A frame loss can occur due to such events as packet loss, late packets, or a jitter buffer error. |
MOS-LQ (destination-to-source) |
Mean Opinion Score for Listening Quality. |
How to Configure IP SLAs RTP-Based VoIP Operations
Configuring and Scheduling an IP SLAs RTP-Based VoIP Operation
Perform this task to configure and schedule an IP SLAs RTP-based VoIP operation.
1.
enable
2.
configure
terminal
3.
ip
sla
operation-number
4.
voip
rtp
{destination-ip-address |
destination-hostname}
source-ip
{ip-address |
hostname}
source-voice-port
{slot
[/ subunit / port : ds0-group-number]}
[codec codec-type]
[duration seconds]
[advantage-factor value]
5.
frequency
seconds
6.
history
history-parameter
7.
owner
text
8.
tag
text
9.
threshold
milliseconds
10.
timeout
milliseconds
11.
exit
12.
ip
sla
reaction-configuration
operation-number
react
monitored-element
[action-type option]
[threshold-type {average
[number-of-measurements] |
consecutive
[occurrences] |
immediate |
never |
xofy [x-value y-value]}]
[threshold-value upper-threshold lower-threshold]
13.
ip
sla
schedule
operation-number
[life {forever |
seconds}]
[start-time
{hh : mm[: ss]
[month day |
day month] |
pending |
now |
after hh : mm : ss}]
[ageout seconds]
[recurring]
14.
exit
15.
show
ip
sla
configuration
[operation-number]
DETAILED STEPS
Troubleshooting Tips
If the IP SLAs operation is not running and not generating statistics, add the verify-data command to the configuration of the operation (while configuring in IP SLA configuration mode) to enable data verification. When data verification is enabled, each operation response is checked for corruption. Use the verify-data command with caution during normal operations because it generates unnecessary overhead.
Use the debug ip sla trace and debug ip sla error commands to help troubleshoot issues with an IP SLAs operation.
What to Do Next
To view and interpret the results of an IP SLAs operation use the show ip sla statistics and show ip sla statistics aggregatedcommands. Checking the output for fields that correspond to criteria in your service level agreement will help you determine whether the service metrics are acceptable.
Configuration Examples for IP SLAs RTP-Based VoIP Operations
Example Configuring an IP SLAs RTP-Based VoIP Operation
The following example shows how to configure an IP SLAs RTP-based VoIP operation:
ip sla 1 voip rtp 10.2.3.4 source-ip 10.5.6.7 source-voice-port 1/0:1 codec g711alaw duration 30 advantage-factor 5 ! ip sla reaction-configuration 1 react FrameLossDS action-type traponly threshold-type consecutive 3 ! ip sla schedule 1 start-time now life forever
Use the show ip sla statistics command in privileged EXEC mode to display the current operational status and statistics for an IP SLAs operation. Use the show ip sla statistics aggregated command in privileged EXEC mode to display the aggregated hourly status and statistics for an IP SLAs operation.
Additional References
The following sections provide references related to the IP SLAs RTP-Based VoIP Operation feature.
Related Documents
Related Topic |
Document Title |
---|---|
Cisco IOS IP SLAs UDP-based VoIP operations for VoIP networks |
Configuring UDP Jitter Operations for VoIP chapter of the Cisco IOS IP SLAs Configuration Guide |
Cisco IOS commands |
|
Cisco IOS IP SLAs commands |
Cisco IOS IP SLAs Command Reference |
Standards
Standard |
Title |
---|---|
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature. |
-- |
MIBs
MIB |
MIBs Link |
---|---|
CISCO-RTTMON-MIB |
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: |
RFCs
RFC |
Title |
---|---|
No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature. |
-- |
Technical Assistance
Description |
Link |
---|---|
The Cisco Technical Support & Documentation website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content. |
Feature Information for IP SLAs RTP-Based VoIP Operations
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Feature Name |
Releases |
Feature Information |
---|---|---|
IP SLAs RTP-Based VoIP Operation |
12.4(4)T |
The Cisco IOS IP Service Level Agreements (SLAs) Internet Control Message Protocol (ICMP) jitter operation provides the capability to generate a stream of ICMP packets to gather network performance-related statistics. Available statistical measurements for the IP SLAs ICMP jitter operation include latency, round-trip time, jitter (interpacket delay variance), and packet loss between a Cisco device (source) and any other IP device (destination). |
IP SLAs RTP-Based VoIP Operation Enhancements |
12.4(6)T |
New statistical measurement options for the source-to-destination data path were added. |