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All packaged together to ensure you pass your audit first time and every time. Invest the right way and reap the rewards! ![]() Please contact us on 1. RFC 68 Applicability November 2012 For example, the RFC 2544 Throughput Test attempts to characterize a maximum reliable load; thus, there will be testing above the maximum that causes packet/frame loss. Browse and Read Rfc 2544 Testing Guide Rfc 2544 Testing Guide Title Type rfc 2544 testing guide PDF sunbeam 2544 user guide PDF sunbeam 2543 2544 hepa air cleaner user guide PDF testing interview questions for experienced in. JDSU T-BERD 6000A RFC-2544 Ethernet Testing Guide Version 1.0 December 19, 2011. RFC-2544 Test Procedures. The T-BERD 6000A is a portable test tools for Ethernet testing. ![]() ITU- T Y. 1. 56. 4 - Wikipedia, the free encyclopedia. ITU- T Y. 1. 56. 4 is an Ethernet service activation test methodology, which is the new ITU- T standard for turning up, installing and troubleshooting Ethernet- based services. It is the only standard test methodology that allows for complete validation of Ethernet service- level agreements (SLAs) in a single test. Purposes. The test methodology applies to point- to- point and point- to- multipoint connectivity in the Ethernet layer and to the network portions that provide, or contribute to, the provisioning of such services. This recommendation does not define Ethernet network architectures or services, but rather defines a methodology to test Ethernet- based services at the service activation stage. This request for comments (RFC) was created in 1. The RFC 2. 54. 4 describes six subtests. This measurement translates into the available bandwidth of the Ethernet virtual connection. Back- to- back or burstability: Measures the longest burst of frames at maximum throughput or minimum legal separation between frames that the device or network under test will handle without any loss of frames. This measurement is a good indication of the buffering capacity of a DUT. Frame loss: Defines the percentage of frames that should have been forwarded by a network device under steady state (constant) loads that were not forwarded due to lack of resources. This measurement can be used for reporting the performance of a network device in an overloaded state, as it can be a useful indication of how a device would perform under pathological network conditions such as broadcast storms. Latency: Measures the round- trip time taken by a test frame to travel through a network device or across the network and back to the test port. Latency is the time interval that begins when the last bit of the input frame reaches the input port and ends when the first bit of the output frame is seen on the output port. It is the time taken by a bit to go through the network and back. Latency variability can be a problem. With protocols like voice over Internet protocol (Vo. IP), a variable or long latency can cause degradation in voice quality. System reset: Measures the speed at which a DUT recovers from a hardware or software reset. This subtest is performed by measuring the interruption of a continuous stream of frames during the reset process. System recovery: Measures the speed at which a DUT recovers from an overload or oversubscription condition. This subtest is performed by temporarily oversubscribing the device under test and then reducing the throughput at normal or low load while measuring frame delay in these two conditions. The different between delay at overloaded condition and the delay and low load conditions represent the recovery time. Networks must support multiple services from multiple customers, and each service has its own performance requirements that must be met even under full load conditions and with all services being processed simultaneously. RFC 2. 54. 4 was designed as a performance tool with a focus on a single stream to measure maximum performance of a DUT or network under test and was never intended for multiservice testing. RFC 2. 54. 4 test cycles can easily require a few hours of testing. This is not an issue for lab testing or benchmarking, but becomes a serious issue for network operators with short service maintenance windows. Network operators that performed service testing with RFC 2. RFC 2. 54. 4 as this KPI was not defined or measured by the RFC. In today's multiservice environments, traffic is going to experience all KPIs at the same time, although throughput might be good, it can also be accompanied by very high latency due to buffering. Designed as a performance assessment tool, RFC 2. KPI individually through its subtest and therefore cannot immediately associate a very high latency with a good throughput, which should be cause for concern. These services are defined at the UNI level with different frame and bandwidth profile such as the service's maximum transmission unit (MTU) or frame size, committed information rate (CIR), and excess information rate (EIR). A single Test Flow is also able to consist of up to 5 different frame sizes called an EMIX (Ethernet Mix). This flexibility allows the engineer to configure a Test Flow very close to real world traffic. These objectives are typically defined and enforced via SLAs. EIR defines the maximum transmission rate above the committed information rate considered as excess traffic. This excess traffic is forwarded as capacity allows and is not subject to meeting any guaranteed performance objectives (best effort forwarding). Overshoot rate defines a testing transmission rate above CIR or EIR and is used to ensure that the DUT or network under test does not forward more traffic than specified by the CIR or EIR of the service. Service configuration test. 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. With only one traffic class, there is no prioritization performed by the network devices since there is only one set of KPIs. As the number of traffic flows increase, prioritization is necessary and performance failures may occur. Services are generated at the CIR, where performance is guaranteed, and pass/fail assessment is performed on the KPI values for each service according to its SLA. The service performance test is designed to soak the network under full committed load for all services and measure performance over medium and long test time. The time frame to complete this section of the test is recommended to follow ITU- T M. Typically this is a round- trip measurement, meaning that the calculation measures both the near- end to far- end and far- end to near- end direction simultaneously. Frame delay variations (FDV): Also known as packet jitter, this is a measurement of the variations in the time delay between packet deliveries. As packets travel through a network to their destination, they are often queued and sent in bursts to the next hop. There may be prioritization at random moments also resulting in packets being sent at random rates. Packets are therefore received at irregular intervals. The direct consequence of this jitter is stress on the receiving buffers of the end nodes where buffers can be overused or underused when there are large swings of jitter. Frame loss ratio (FLR): Typically expressed as a ratio, this is a measurement of the number of packets lost over 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 loss ratio with reference to the SAC: Typically expressed as a Pass / Fail indication. SAC (Service Acceptance Criteria) is the part of the network operators SLA which references the FLR requirement for the network path under test. Availability (AVAIL): Typically expressed as a % of up time for link under test for example does the network pass the 5.
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