Y.1564 is an Ethernet
service activation test methodology and is the standard for turning up,
installing, and troubleshooting Ethernet and IP based services. Y.1564 is the
only standard test methodology that allows a complete validation of Ethernet
service-level agreements (SLAs) in a single test.
testing (SAT) is designed to measure the ability of a Device Under Test (DUT)
or a network under test to properly forward traffic in different states.
Effective with Cisco IOS XE Everest Release 16.5.1, 10 Gigabit
(10G) SAT session is supported on Cisco RSP2 and Cisco RSP3
Modules. Any SAT session with a rate-step greater than or equal to 1 Gbps
is considered as 10G SAT session.
of ITU-T Y.1564 has three key objectives:
The following Key
Performance Indicators (KPI) metrics are collected to ensure that the
configured SLAs are met for the service or stream. These are service acceptance
- To serve as a network SLA
validation tool, ensuring that a service meets its guaranteed performance
settings in a controlled test time.
- To ensure that all services
carried by the network meet their SLA objectives at their maximum committed
rate, thus proving that under maximum load, network devices and paths can
support all traffic as designed.
- To perform medium-term and
long-term service testing, confirming that network elements can properly carry
all services while under stress during a soaking period.
- Information Rate (IR) or
throughput—Measures the maximum rate at which none of the offered frames are
dropped by the device under test (DUT). This measurement translates into the
available bandwidth of the Ethernet virtual connection (EVC).
- Frame Transfer Delay (FTD) or
latency—Measures the round-trip time (RTT) taken by a test frame to travel
through a network device, or across the network and back to the test port.
FTD is not
supported on Cisco RSP3 Module.
- Frame Loss Ratio
(FLR)—Measures the number of packets lost from the total number of packets
sent. Frame loss can be due to a number of issues such as network congestion or
errors during transmissions.
- Frame Delay Variation (FDV)
or jitter—Measures the variations in the time delays between packet deliveries.
FLR is not
supported on Cisco RSP3 Module.
interconnect segments, forwarding devices (switches and routers) and network
interface units are the basis of any network. If a service is not correctly
configured on any one of these devices within the end-to-end path, network
performance can be greatly affected, leading to potential service outages and
network-wide issues such as congestion and link failures. Service performance
testing is designed to measure the ability of DUT or network under test, to
correctly forward traffic in different states. The Cisco implementation of
ITU-T Y.1564 includes the following service performance tests:
supports four operational modes: two-way statistics collection, one-way
statistics collection, passive measurement mode, and traffic generator mode.
Statistics are calculated, collected, and reported to the IP SLAs module. The
statistics database stores historical statistics pertaining to the operations
that have been executed.
- One-way statistics
collection—Both the passive measurement mode and the traffic generator mode are
used in conjunction with each other. One device sends traffic as the generator
and another device receives traffic in the passive mode and records the
statistics. The passive mode is distinct from the two-way mode, where the
remote device records statistics instead of looping back the traffic and the
sending device records only the transmit statistics.
- Two-way statistics
collection—All the measurements are collected by the sender. The remote target
must be in the loopback mode for the two-way statistics to work. Loopback mode
enables the traffic from the sender to reach the target and be returned to the
- Passive measurement mode—This
mode is enabled by excluding a configured traffic profile. A passive
measurement operation does not generate live traffic. The operation collects
only statistics for the target configured for the operation.
- Traffic generator mode—This
mode records transmit statistics for the number of packets and bytes sent.