Telecom and Cable MSO networks are comprised of a myriad of geographically diverse network elements connected together with fiber optic cabling, copper twisted pairs of wires, coax cables, and radio links. Each network element, such as customer premise equipment, network switches, routers, radios are each controlled by an Element Management System that in turn feeds into and are controlled by a computer-based network and software called the Operating Support System (OSS).
Telecom testing, measuring, monitoring and service assurance is an additional and vital operations aspect of building, operating, and especially troubleshooting telecom networks.
AimValley works with some of the world’s largest and best providers of test units and systems and in addition, AimValley offers some specific Smart SFPs to support Service Assurance network monitoring systems.
Primarily these are SFP-based loop back and packet reflectors. AimValley refers to these devices as OAM devices.
Here are some examples of how AimValley is helping telecom testing, measuring and monitoring companies.
Ultra High-Speed Ethernet Packet Generation
As packet transport rates continue to rise, AimValley works with leading providers of test solutions, designing boards and modules for the generation of packet data streams. With historical solutions in 1GigE, 10GigE, and 100GigE and now solutions that run at 400 GigE, 800GigE, and soon Terabit Ethernet, AimValley provides cutting edge technology for the next generation of high-speed testing.
Bit Error Rate & Performance Testing
There are two methods in determining the proper performance of a telecom service. Live traffic & frames can be observed, measured, and possibly captured for analysis, or alternatively artificial traffic can be synthesized and injected into the telecom service (or network element) in place of live packet streams.
Typically, the latter is used to perform a turn-up and test of the initial service and it is more common for monitoring of live traffic to be applied once the service is up and running. In the case of performance testing, a very lengthy but highly predictable bitstream is transmitted into the service being tested. Then, at another location that same injected pattern is recovered into the test and measurement equipment, and an assessment of the parameters and attributes of the received data, and therefore, an evaluation of performance is made.
AimValley’s expertise in FPGA design is paramount in the company’s ability to serve its Telecom test, measure, and service assurance customers as FPGA technology is adept at processing and evaluating very high bitstreams on a bit by bit basis with no uncertainty.
Timing & Synchronization Measurements
AimValley has tremendous experience in synchronization, time stamping, and clock recovery. All of these are vital parameters of today’s complex networks. This expertise is available to be leveraged by companies working on applications to monitor and measure such attributes of a network. One thing is for sure, Test & Measurement companies need to avoid introducing errors into otherwise error-free bit and packet streams. Managing clocks and synchronization is often vital in telecom test equipment.
Algorithms
Not all testing is as straightforward as a bit error.
In many cases the evaluation required is based on much more of a “somewhat” error-tolerant data stream or the parameters may require the evaluation of signals that are fundamentally analog in nature. For example, the human ear can tolerate some clicks, pops, noise, delay, echo, and dropouts but not too much and not for too long. Likewise, streaming video can use buffers and artificially introduced delay in order to repair or replace damaged packets, but there are limits to such techniques after which the end user’s service quality is adversely affected.
AimValley has worked on many algorithms that are helpful in telecom including those that enable DSL vectoring and bonding. VoIP and Streaming Video.
Smart SFP for OAM
AimValley has developed and continues to develop stand-alone box-based Network Interface Devices (NIDs), however, it is becoming more commonplace for network service providers to build intelligent loopback capabilities and the testing and monitoring functionalities of TWAMP, Y.1731, and Y.1564 into SFP pluggable devices. AimValley is a world leader in GigE and now 10 GigE Smart SFPs that provide intelligent endpoint capabilities. AimValley provides these to Service Assurance providers and Telecom NEMs in support of their offered solutions. As is the case with all AimValley SmartSFPs they can be pre-configured, plug and play, remotely configured, or managed using AimValley’s Titan software that is designed to be integrated into Network Elements.
International Telecommunications Unit (ITU)
AimValley develops its telecoms solutions according to various ITU standards.
ITU-T Y.1731
The Y.1731 standard is used to implement end-to-end connectivity detection, loopback detection, and link trace on Metro Ethernets. It also provides test diagnosis and performance monitoring functions such as frame loss measurement, frame delay measurement, frame jitter measurement, and throughput measurement.
Ethernet in the First Mile and Connectivity Fault Management is used to detect link faults for carriers. Y.1731, an enhancement of CFM, can be configured to monitor service performance.
Hierarchical Ethernet operation, administration, and maintenance (OAM) need to be provided based on the network architecture, as shown in the below figure.
ITU-T Y.1564
This standard is designed to serve as a network service level agreement validation method 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 pre-defined SLA objectives at their maximum committed rate, and to perform medium- and long-term service testing, confirming that network elements can properly carry all services while under stress during a soaking period.
ITU-T Y.1564 defines an out-of-service test methodology to assess the proper configuration and performance of an Ethernet service prior to customer notification and delivery. 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.
Protocols
Telecom networks and the services offered feature a large variety of data rates, packetization schemes, multiplexing techniques, aggregations, and channelization. The test, measurement, and monitoring objective may not be to measure the performance of the entire data stream but rather a channel, tributary, or fraction of the service.
In fact, the stacked and complex mixtures of formats and protocols can themselves be sources of the issues to be uncovered, evaluated, and optimized.
This is an area where AimValley really excels as we have a long history of building network gear that performs such packetizations, aggregations, and multiplexing. Our capabilities include TDM (T1, E1, DS-3), all rates of SONET / SDH, OTN, High-Speed Ethernet, with attributes and protocols including MPLS, CPRI, VLAN, DHCP, IPv4, IPv6, CES, Pseudowires, Tunneling and many, many more.
In the Test & Measurement domain, we have the technical knowledge to drill down into channels, streams, and encoded streams to provide the measurements required.
AimValley Test & Measurement Expertise
- High-Speed generation.
- Injected impairments and monitoring of Ethernet packets.
- Algorithms for high-speed transport.
- Optical physical layer measurements.
- Complex protocol analysis.
AimValley proven track record
AimValley’s OAM Smart SFPs are offered to service assurance solutions providers and NEMs to support;
- intelligent loopbacks
- in-service performance monitoring, incl. TWAMP
- round-trip delay
- Y.1731, Y.1564 functions.
