Assessing the Performance of Ethernet Services
EXFO’s RTU-310 IP Services Test Head enables carriers to ensure the reliability and performance of their Ethernet-based services. Its wide range of test functionalities provide all the necessary measurement tools for service turn-up, troubleshooting as well as verifying service-level agreements (SLAs) between service providers and their customers. This carrier-class 1U rack-mounted, central office (CO)-based device, combined with its portable counterparts, EXFO’s award winning FTB-8510B Packet Blazer Ethernet Test Module or the AXS-200/850 Ethernet Test Set, simplify and accelerate the deployment of Ethernet services. In fact, the RTU-310 is the functional equivalent of the FTB-8510B and supports all the test features found in the portable version.
Flexible End-to-End Testing from a Centralized Point
With the RTU-310 IP Services Test Head, a single technician can perform end-to-end testing through control of the remote unit—either an FTB-8510B Packet Blazer or another RTU-310 via the LAN connection under test. This unique approach gives service providers access to test results for each direction of test, which is essential to fully qualify Ethernet services. It is also possible to perform end-to-end testing by using the Smart Loopback mode where the remote unit will return traffic to the local unit by swapping packet overhead up to layer 4 of the OSI stack.
The RTU-310 tests connectivity in its native format: 10/100/1000Base-T, 100Base-FX, 100Base-LX, 1000Base-SX, 1000Base-LX and 1000Base-ZX for LAN-to-LAN services delivered via next-generation SONET/SDH, SONET/SDH hybrid multiplexers, switched Ethernet, VLANs, dark fiber, WDM, FTTx systems or other means.
Key Features
- Complete EtherSAM™ (ITU-T Y.156sam) test suite allowing full validation of today’s Ethernet services (bidirectional results through dual test set)
- Throughput, back-to-back, latency and frame loss measurements as per RFC 2544 (bidirectional results through dual test set)
- Multistream generation and analysis, providing per-stream measurements for throughput, latency, frame loss and packet jitter
- True wire-speed and stateful TCP throughput testing
- PBB-TE and MPLS support for carrier Ethernet
- IPTV testing and analysis
- Packet jitter measurement (IP packet-delay variation as per RFC 3393) to qualify Ethernet transport networks for transmission of delay-sensitive traffic such as voice-over-IP (VoIP) and video
- Internet protocol version 6 (IPv6) testing
- Q-in-Q capability for up to three layers of stacked VLANs
- Dual port capability for simultaneous traffic generation and reception at 100 % wire speed for 10/100/1000Base-T, 100Base-FX, 100Base-LX, 1000Base-SX, 1000Base-LX or 1000Base-ZX full-duplex networks at all packet sizes
- Ethernet in the First Mile 802.3ah testing
- Fibre Channel 1x and 2x test suite
- Expert mode capability to set test thresholds for clear pass/fail test results
- Configurable advanced filters for in-depth network troubleshooting
- Service disruption time measurement
- Ethernet Through mode
- Remote control capability through EX-Vu or VNC software
- Easy-to-use smart user interface (SUI) for configurable screens, customization of test suites, as well as real-time and historical performance reporting
- Up to 1 Gbit/s full-line-rate data capture and decode
EtherSAM: The New Standard in Ethernet Testing
ITU-T Y.156sam is the newly introduced draft standard for turning-up and troubleshooting carrier Ethernet services. This new methodology is completely adapted to today’s Ethernet services especially mobile backhaul and commercial services. Up to now, RFC 2544 has been the most widely used methodology. However, it was designed for network device testing in the lab, not for services testing in the field. Y.156sam is the first testing standard developed for the field. It has a number of advantages over the RFC 2544 including validation of critical SLA criteria such as packet jitter and QoS measurements. This methodology is also significantly faster, therefore saving time and resources while optimizing QoS.
Contrary to other methodologies, EtherSAM supports new multiservice offerings. It can simulate all types of services that will run on the network and simultaneously qualify all key SLA parameters for each of these services. Moreover, it validates the QoS mechanisms provisioned in the network to prioritize the different service types, resulting in more accurate validation and much faster deployment and troubleshooting. EtherSAM is comprised of two phases, the Network Configuration Test and the Service Test.
Network Configuration Test
The Network Configuration Test consists in sequentially testing each service. It validates that the service is properly provisioned and that all specific KPIs or SLA parameters are met.
Service Test
Once the configuration of each individual service is validated, the Service Test simultaneously validates the quality of all the services over time.
EtherSAM Bidirectional Results
EXFO’s EtherSAM approach proves even more powerful as it executes the complete ITU-T Y.156sam test with bidirectional measurements. Key SLA parameters are measured independently in each test direction, thus providing 100 % first-time-right service activation—that is the highest level of confidence in service testing.
RFC 2544 Test Suite
The RTU-310 IP Services Test Head can perform the RFC 2544 test suite for 10/100/1000Base-T, optical 100 Mbit/s and GigE interfaces at all frame sizes and at full line rate, allowing the provider to certify that the circuit is efficient and error-free at 100 % utilization. More importantly, when in Dual Test Set mode, the RTU-310 allows bidirectional testing, providing independent RFC 2544 test results for both directions (local to remote and remote to local). This is especially important when testing Ethernet services as traffic from each direction often takes different paths in the network. Performance results can therefore vary depending on the direction. The RTU-310 supports automated RFC 2544 testing, which helps ensure repeatable results.
Automation also provides ease of use for field technicians by enabling accurate, efficient measurements and results through a clear and simple pass/fail indication. In addition, the RTU-310 generates reports that can be given to customers for future reference related to their specific SLAs.
Efficient Testing Leads to Reliable Performance
TCP Throughput
The Internet protocol (IP) and transmission control protocol (TCP) together form the essence of TCP/IP networking. While IP deals with the delivery of packets, TCP provides the integrity and assurance that the data packets transmitted by one host are reliably received at the destination. Applications such as hypertext transfer protocol (HTTP), email or file transfer protocol (FTP) depend on TCP as their delivery assurance mechanism within networks. Customers deploying such applications expect not only physical and link-level SLAs from their service providers, but assurance that their TCP traffic requirements will be supported across the network. The TCP throughput feature on the RTU-310 offers Ethernet service providers the capability of measuring and validating that the services offered to their customers support the TCP traffic performance they expect.
PBB-TE and MPLS: Carrier Ethernet Transport Solution Testing
As technologically sophisticated business and residential consumers continue to drive demand for premium, high-bandwidth data services such as voice and video, service providers worldwide are evolving their transport infrastructures to support these bandwidth and quality-intensive services. No longer is an all-IP core sufficient—providers must now expand their IP convergence to the edge/metro network in a cost-effective, quality-assured manner. Ethernet has long been accepted as an inexpensive, scalable, data-networking solution in LAN environments. The stringent QoS expectations require solutions that tap into the cost-effectiveness of Ethernet without sacrificing the benefits of connection-oriented (albeit it costly) TDM solutions such as SONET/SDH.
Two Ethernet tunneling technologies address these requirements: provider backbone bridge-traffic engineering or PBB-TE (also referred to as PBT) and transport multiprotocol label switching (MPLS). These two technologies enable connection-oriented Ethernet, providing carriers with a means of offering scalable, reliable and resilient Ethernet services. The PBB-TE and MPLS options on the RTU-310 IP Services Test Head offer service providers a comprehensive field tool to efficiently qualify Ethernet services from end-to-end, validating metro and core tunneling technologies.
Ethernet Advanced Troubleshooting
The RTU-310 provides a number of advanced features essential for in-depth troubleshooting in the event of network failures or impairments.
The advanced filtering option allows the user to configure up to ten filters each with up to four operands, which will be applied to the received Ethernet traffic. Detailed statistics are available for each configured filter, providing the user with critical information required to pinpoint specific problems. Other advanced troubleshooting tools include advanced auto-negotiation, flow control capabilities as well as Ethernet in the First Mile 802.3ah support.
The RTU-310 also supports full-line-rate data capture and decode. This key troubleshooting tool enables field technicians to easily identify complex network issues. The comprehensive capture feature includes the capability to configure capture filters and triggers to quickly zero-in on network events.
IPTV Testing and Analysis
The IPTV software option available on the RTU-310 leverages the current frame-analysis engine, delivering high-performing measurement capabilities and providing users with over 45 different IPTV metrics and statistics in a powerful fixed IPTV test platform. The key features and capabilities provided with this software option include RFC 4445 media delivery index (MDI), TR 101 290 priority 1 metrics, in addition to program clock reference jitter, IGMP support, stream rate and bandwidth utilization on 100 simultaneous MPEG-2, MPEG-4 or VC-1 streams. Usability features include user-configurable alarm thresholds for MDI and other selected metrics, enabling customizable test sequences as well as an auto-stream detection capability that automatically discovers valid IPTV streams within the Ethernet layer.
Additionally, stream IP addresses can be linked to a user-definable stream name through an alias table typically containing the name of the broadcast channel.
The RTU-310 with its IPTV software option offers service providers the most effective tool to quickly and efficiently test and monitor IPTV streams over their network. For more information on the RTU-310 IP Services Test Head IPTV option, refer to the FTB-8510B specification sheet.
EtherBERT™
Ethernet is increasingly being carried across a variety of layer 1 media over longer distances. This creates a growing need for the certification of Ethernet transport on a bit-per-bit basis, which can be done using bit-error-rate testing (BERT). BERT uses a pseudo-random binary sequence (PRBS) encapsulated into an Ethernet frame, making it possible to go from a frame-based error measurement to a bit-error-rate measurement. This provides the bit-per-bit error count accuracy required for acceptance testing of physical-medium transport systems. BERT-over-Ethernet should usually be used when Ethernet is carried transparently over layer 1 media, in cases such as Ethernet over DWDM, CWDM or dark fiber.
Ethernet QoS Measurements
Data services are making a significant shift toward supporting a variety of applications on the same network. Multiservice offerings such as triple-play services have fuelled the need for QoS testing to ensure the condition and reliability of each service and fully qualify SLA parameters. The RTU-310 allows service providers to simultaneously simulate and qualify different applications through its multistream application. The user has the capability to configure up to ten streams with different Ethernet and IP QoS parameters such as VLAN ID (802.1Q), VLAN Priority (802.1p), VLAN stacking (802.1ad Q-in-Q), ToS and DSCP. Specific stream profiles to transmit VoIP, video and data can be selected for each stream. Throughput, latency, frame loss and packet jitter (RFC 3393) measurements are also available simultaneously for each stream, allowing fast and in-depth qualification of all SLA criteria.
Fibre Channel Network Integrity Testing
EXFO’s RTU-310 IP Services Test Head also supports comprehensive Fibre Channel testing.
Interfaces
This head supports the following Fibre Channel interfaces:
Applications
Since most storage area networks cover large distances and Fibre Channel has stringent performance attributes that must be respected, testing at each phase of network deployment is imperative to ensure appropriate service levels. The RTU-310’s Fibre Channel option provides full wire-speed traffic generation at FC-0, FC-1 and FC-2 logical layers, allowing BER testing for link integrity measurements. Latency, buffer-to-buffer credit measurements for optimization and login capabilities are also supported.
Buffer-to-Buffer Credit Estimation
Buffer-to-buffer credits are part of the flow control engine for Fibre Channel connections. This is a crucial configuration parameter for optimal network performance. Usually, network administrators calculate the value by taking the traveled distance and the data rate into consideration. However, since latency issues are not considered, poor accuracy is to be expected. The RTU-310 is capable of estimating buffer-to-buffer credit values with respect to latency by calculating the distance according to the round-trip latency time.
Command and Control
Remote Management
The user interface for the RTU-310 IP Services Test Head is accessible via EX-Vu remote management software. It enables a remote connection to the instrument, as well as providing the graphical user interface (GUI) for test setup and device management. The EX-Vu application is supported on any Windows based workstation and allows for simplified remote testing and data analysis, as well as remote monitoring. Up to five simultaneous EX-Vu sessions can be supported via a standard Ethernet connection to the platform.
Automated Test Scripting
The RTU-310 supports .NET programming environment for users who prefer to build their automation test routines. The unit comes with a built-in macro-recorder, which allows users to easily record their test actions and automatically create test scripts; this also enables them to build standard test routines that can easily be accessed and run by technicians with little or no manual intervention. Scripts from the macro-recorder can be used as the basis for larger automation routines, which can be created or edited in any .NET environment.
Test Logger and Reporting
The RTU-310 supports a detailed test logger and test reporting tools, enabling users to view any errors/alarms that occurred during the test interval, which can then be used for post-processing of results or SLA conformance validation.
Test Control Through BrixWorx™
RTU-310 is an integral part of EXFO’s BrixNGN Service Assurance solution for Ethernet services. BrixNGN enables providers to continuously collect, correlate, analyze, and visualize critical QoS and QoE data for the Ethernet services they are selling to their customers. This solution enables capacity planning and service turn-up verification, as well as identification, diagnosis and quickly resolving network and service issues before customers are affected—thereby guaranteeing performance and quality.
As part of the BrixNGN solution, the RTU-310 is managed and test configurations are all performed via the BrixWorx software engine. The RTU-310 can be used for service turn-up, troubleshooting or ongoing 24/7 SLA monitoring. At service turn-up time, providers can run a series of tests that enable them to benchmark the service they are making available to their customers. This data can be used as a baseline for the performance of the service and can be used to produce birth certificates for the service. If a particular service shows quality problems, the RTU-310 platform can be used to launch diagnostic tests for that service to identify and isolate the source of the problem. Finally, the RTU-310 can be used for ongoing monitoring of services as part of an SLA agreement. Periodic tests are automatically launched that enable a provider to collect data about each of their services; this data, along with data reported by other test systems, is collected and stored in the BrixWorx central data storage. The data is then aggregated and analyzed to generate service-level alarms when thresholds are violated, as well as to provide executives and operations with historical reports of the service performance.