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Software Configuration Guide—Release 15.0(2)SG
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Chapter 60 Configuring Cisco IOS IP SLA Operations
About Cisco IOS IP SLA
options such as source and destination IP address, User Datagram Protocol (UDP)/TCP port numbers, a
type of service (ToS) byte (including Differentiated Services Code Point [DSCP] and IP Prefix bits),
Virtual Private Network (VPN) routing/forwarding instance (VRF), and URL web address.
Because Cisco IP SLAs is Layer 2 transport independent, you can configure end-to-end operations over
disparate networks to best reflect the metrics that an end user is likely to experience. IP SLAs collects a
unique subset of these performance metrics:
• Delay (both round-trip and one-way)
• Jitter (directional)
• Packet loss (directional)
• Packet sequencing (packet ordering)
• Path (per hop)
• Connectivity (directional)
• Server or website download time
Because Cisco IOS IP SLAs is SNMP-accessible, it can also be used by performance-monitoring
applications such as CiscoWorks Internetwork Performance Monitor (IPM) and other third-party Cisco
partner performance management products. You can find more details about network management
products that use Cisco IOS IP SLAs at this URL:
http://www.cisco.com/go/ipsla
Using IP SLAs can provide these benefits:
• Service-level agreement monitoring, measurement, and verification.
• Network performance monitoring
–
Measures the jitter, latency, or packet loss in the network.
–
Provides continuous, reliable, and predictable measurements.
• IP service network health assessment to verify that the existing QoS is sufficient for new IP services.
• Edge-to-edge network availability monitoring for proactive verification and connectivity testing of
network resources (for example, shows the network availability of an NFS server used to store
business critical data from a remote site).
• Troubleshooting of network operation by providing consistent, reliable measurement that
immediately identifies problems and saves troubleshooting time.
This section includes this information about IP SLAs functionality:
• Using Cisco IOS IP SLAs to Measure Network Performance, page 60-3
• IP SLAs Responder and IP SLAs Control Protocol, page 60-4
• Response Time Computation for IP SLAs, page 60-5
• IP SLAs Operation Scheduling, page 60-6
• IP SLAs Operation Threshold Monitoring, page 60-6
Using Cisco IOS IP SLAs to Measure Network Performance
You can use IP SLAs to monitor the performance between any area in the network—core, distribution,
and edge—without deploying a physical probe. It uses generated traffic to measure network performance
between two networking devices. Figure 60-1 shows how IP SLAs begins when the source device sends
a generated packet to the destination device. After the destination device receives the packet, depending
