EtherSAM: the new standard in Ethernet testing
ITU-T Y.1564 is the new standard for turning up and troubleshooting Carrier Ethernet services. This 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. ITU-T Y.1564 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 service configuration test and the service performance test.
Service configuration test
The service 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. A ramp test and a burst test are performed to verify the committed information rare (CIR), excess information rate (EIR), committed burst size (CBS) and excess burst size (EBS).
Service performance Test
Once the configuration of each individual service is validated, the service performance 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.1564 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 FTB-8510B Packet Blazer can perform the RFC 2544 test suite for 10/100/1000M 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 Packet Blazer allows bidirectional testing, providing independent RFC 2544 test results for each direction (local to remote and remote to local) simultaneously. 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 Packet Blazer supports automated RFC 2544 testing, including throughput, latency, burst (back-to-back) and frame loss. 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 Packet Blazer 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), e-mail 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 Packet Blazer™ offers Ethernet service providers the capability of measuring and validating that the services offered to their customers support the TCP traffic performance they expect.
MPLS, MPLS-TP and PBB-TE: 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.
Ethernet tunneling technologies such as Provider Backbone Bridge-Traffic Engineering or PBB-TE (also referred to as PBT) and transport MPLS address these requirements. These 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 FTB-8510B Packet Blazer 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 FTB-8510B 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. Additionally, the FTB-8510B supports a traffic scan feature that allows quick identification and monitoring of VLAN and MPLS flows on the network. This can help clearly identify top bandwidth users.
The FTB-8510B 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 FTB-8510B, 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 portable 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 combination of the portable FTB-500 platform and the FTB-8510B Packet Blazer with the 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 FTB-8510B Packet Blazer IPTV option, please refer to the IPTV Test Option specification sheet.
* The MDI feature of the IPTV software option is not available in the USA.
EtherBERT™
Ethernet is increasingly 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 FTB-8510B Packet Blazer 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 profile s t o 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 FTB-8510B Packet Blazer module also supports comprehensive Fibre Channel testing.
Interfaces
This module supports the following Fibre Channel interfaces:
| Interface |
Rate (Gbit/s) |
| 1x |
1.0625 |
| 2x |
2.125 |
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. EXFO’s FTB-8510B 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 FTB-8510B module is capable of estimating buffer-to-buffer credit values with respect to latency by calculating the distance according to the round-trip latency time.
Latency
Transmission of frames in a network is not instantaneous and is subject to multiple delays caused by the propagation delay in the fiber and by processing time inside each piece of network equipment. Latency is the total accumulation of delays between two endpoints. Some applications such as VoIP, video and storage area networks are very sensitive to excess latency. It is therefore critical for service providers to properly characterize network latency when offering Fibre Channel services. From the latency measurement that they perform, the FTB-8510B Packet Blazer estimates buffer-to-buffer credit value requirements.
