AUTOMOTIVE ETHERNET WHITE PAPER. Xena test solutions can verify quality, functionality and performance of BroadR-Reach Ethernet equipment.

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1 WHITE PAPER AUTOMOTIVE ETHERNET OVERVIEW The autmtive industry is evlving rapidly. The newest mdels have features that represent unparalleled innvatin - cars that can cmmunicate with each ther, the rad-side infrastructure, the Internet, plus highly advanced in-car inftainment systems. Cars are als being equipped with sensr-based safety systems that can dramatically imprve traffic safety by virtually eliminating crashes. And we are nearing a pint where fully autmated vehicles that can handle all driving tasks will sn be cmmercially available. Mst f these new features and applicatins rely n bandwidth hungry electrnics which require cstly and cmplex cabling. This is a key factr increasing the price and weight f the cars. T cunter this, the newly apprved BradR-Reach 100 Mbit/s Autmtive Ethernet specificatin seeks t ptimize in-car cabling, based n 100 Mbit/s Ethernet running ver a single unshielded twisted pair cpper wire. A netwrk based n the BradR-Reach specificatin fr in-car cmmunicatin will significantly reduce bth cst and weight f the required cabling. Xena test slutins can verify quality, functinality and perfrmance f BradR-Reach Ethernet equipment. Testing BradR-Reach Ethernet equipment is essential fr verifying its quality, functinality and perfrmance. The Xena M6SFP 6-prt 1Gbps test mdule prvides pwerful testing capabilities fr testing and verifying BradR-Reach autmtive Ethernet slutins.

2 Autmtive Ethernet Cntents OVERVIEW... 1 Intrductin... 3 BradR-Reach 100 Mbit/s Autmtive Ethernet... 4 Legacy Autmtive Netwrks... 5 Autmtive Ethernet Standardizatin... 6 Prtcl Stack... 6 BradR-Reach capable switches... 8 BradR-Reach media cnverters Base-T1 media cnverters... 8 Autmtive Ethernet Test Requirements... 8 Xena Netwrks Autmtive Ethernet Slutins... 9 Testing up t Layer Testing frm 10 Megabit/s t 1 Gigabit/s Test Autmatin CONCLUSION... 11

3 Intrductin Mdern cars are laded with sphisticated applicatins and functins that imprve traffic safety, fuel cnsumptin and user cnvenience. These include: 1. In-car applicatins: Examples are Advanced Driver Assistance Systems (ADAS) like: Adaptive cruise cntrl (ACC), autmatic parking, blind spt mnitring, cllisin avidance systems, driver drwsiness detectin, hill descent cntrl, lane departure warning systems, lane change assistance, parking sensrs, pedestrian prtectin systems, rain sensrs, surrund view systems, traffic sign recgnitin, & wrng-way driving warnings. Figure 1: Vehicle t X cmmunicatin (V2X) 2. V2X: They als cver inftainment systems that require Internet access knwn as V2X (Vehicle t X where the X can by just abut any clud-based cmmunicatin service).

4 3. V2V: Vehicle t Vehicle cmmunicatin (V2V) cvers cars that can cmmunicate with each ther. Figure 2: Vehicle t Vehicle cmmunicatin (V2V) In additin t the new features and applicatin als legacy mechanical r hydraulic systems are mving t electrnically cntrlled systems (x by wire). This is implemented with a number f Electrnic Cntrl Units (ECUs), which are embedded systems cntrlling ne r mre f the electrical system in a car. All f these electrnic systems require a large and cmplex electrical cabling t the extent where this is nw the car s third heaviest cmpnent after the chassis (first) and the engine (secnd). BradR-Reach 100 Mbit/s Autmtive Ethernet The purpse f the BradR-Reach 100 Mbit/s Autmtive Ethernet standard seeks t address this issue t reduce cnnectivity csts and cabling weight by allwing multiple in-vehicle systems t simultaneusly access infrmatin ver unshielded single twisted pair cable.

5 The OPEN Alliance BradR-Reach (OABR) specificatin defines a single Twisted Pair 100 Mbit/s interface. OABR will reduce cst and weight f in-car netwrks as nly a single wire pair will be used. Signals are sent bidirectinal n the wire pair. There are ther 100 Mbit/s Autmtive Ethernet slutins than BradR-Reach and the develpment will nt stp at this speed. 1 Gigabit Autmtive Ethernet will be next step implemented as Reduced Twisted Pair Gigabit Ethernet (RTPGE) Gbps RTPGE 100 Mbps ther 100 Mbps OABR Figure 3: Autmtive Ethernet prt frecast (number f prts in cnsumer vehicles prduced) Surce: Gartner 2014 Legacy Autmtive Netwrks Autmtive netwrks have been used in cars fr many years. Sme examples are: CAN (Cntrller Area Netwrk) Serial bus, data rates up t 1 Mbit/s Shared medium with CSMA/CR Widely spread, develped by Rbert Bsch GmbH Standardized in ISO FlexRay Serial bus (single r dual channel), data rates up t 10 Mbit/s Shared medium with TDMA Develped by the FlexRay Cnsrtium Designed t be faster and mre reliable than CAN is als mre expensive Standardized in ISO LIN (Lcal Intercnnect Netwrk) Serial netwrk with 16 ndes (ne master, up t 15 slaves), data rates up t 20 kbit/s Lwer cst and lwer bandwidth than CAN Develped by the LIN Cnsrtium MOST (Media Oriented Systems Transprt) Shared ring with up t 64 devices, data rates up t 150 Mbit/s Fr cntrl and streaming inftainment data Prprietary slutins 100 Mbit/s Ethernet (100BASE-TX)

6 Diagnstics and firmware upgrades during car service Nrmally nt used while cars perate due t EMC issues Standardized in ISO :2011 Autmtive Ethernet Standardizatin Ethernet is tday used fr all kinds f cmmunicatin as it is cst effective and relatively simple. When car manufacturers wanted t ptimize cst and weight f in-car cpper cabling it was bvius t lk fr a cmmunicatin slutin based n Ethernet. Legacy 100 Mbit/s Ethernet n cpper wires (100BASE-TX) was nt an ptin due t EMC issues. Furthermre the gal was t use bi-directinal cmmunicatin ver a single balanced twisted pair cable (with a length up t 15 m) - 100BASE-TX uses tw twisted pairs. In Nvember 2011 the OPEN (One-Pair EtherNet) Alliance Special Interest Grup (SIG) (OPEN Alliance SIG) was frmed. The fllwing mnth the Alliance fficially released the BradR-Reach autmtive Ethernet specificatin, which was riginally develped by Bradcm. By the end f 2016 the Alliance had mre than 300 members including car manufacturers, semicnductr manufacturers and many thers. The bjectives fr the BradR-Reach specificatin are: Prvide a PHY that supprts full duplex peratin at 100 Mbit/s ver ne pair unshielded twisted pair (UTP) r better cable. Prvide cmpatibility with the MII (IEEE Clause 22) and IEEE MAC perating at 100 Mb/s. Bit Errr Rate f less than r equal t 1e-10 ver a nminal channel (ver a ne pair UTP cable). The IEEE equivalent t the BradR-Reach specificatin was standardized as 100BASE-T1 in IEEE 802.3bw-2015 Clause 96 in Octber IEEE has als wrked n higher speed Autmtive Ethernet in the IEEE P802.3bp 1000BASE-T1 PHY Task Frce. The task frce defined 1 Gigabit Autmtive Ethernet implemented as Reduced Twisted Pair Gigabit Ethernet (RTPGE) and has nw cmpleted the IEEE 802.3bp standard fr 1 Gigabit/s peratin ver a single twisted pair cpper cable. IEEE 802.3bp was apprved June 2016 and is als knwn as 1000Base-T1. Prtcl Stack The Ethernet prtcl stack is based n the seven-layer OSI mdel f cmputer netwrking. The BradR-Reach specificatin and the 100BASE-T1 standard address Layer 1 f the OSI mdel which cntains the fllwing sublayers:

7 Sublayers Functins PCS (Physical Cding Sublayer) determine that a functinal link has been established (Link Training) scrambling/descrambling cding PMA (Physical Medium Attachment Sublayer) framing ctet synchrnizatin/detectin PMD (Physical Medium Dependent Sublayer) Table 1: Layer 1 sublayers the transceiver fr the physical medium Aut-negtiatin is nt used in the BradR-Reach Layer 1 as the aut-negtiatin latency (which culd be up t a few secnds) may exceed the start-up time requirements f autmtive netwrks. FORCE mde is used instead. The BradR-Reach specificatin is based n the IEEE Gigabit Ethernet (1000BASE-T) and the Fast Ethernet (100BASE-TX) standards. There are hwever differences as shwn in table 2. BradR-Reach 1000Base-T 100Base-TX Duplex mde Full Duplex Full Duplex Dual Simplex Wires Single twisted pair Fur twisted pairs Tw twisted pairs Mdulatin PAM-3 PAM-5 MLT-3 Signaling levels Symbl rate 66.7 Msps 125 Msps 125 Msps Bandwidth 33.3 MHz MHz MHz Decisin feedback Equalizatin Ech cancellatin Decisin feedback Equalizatin Ech and crsstalk cancellatin Partial respnse transmit filter Additinal level fr errr crrectin cding Decisin feedback Equalizatin Table 2 Differences between BradR-Reach, 1000BASE-T and 100BASE-TX

8 As shwn in table 3 the BradR-Reach bandwidth requirement is less than half the 100BASE-TX bandwidth requirement, which means that BradR-Reach can perate ver cables with lwer cst and quality. In additin the PAM-3 mdulatin will reduce EMI and allw a mre aggressive EMC filtering. BradR-Reach capable switches Several vendrs ffer switches with BradR-Reach capabilities. Sme examples are: Bradcm BCM integrated BradR-Reach PHYs + 2 uplink prts NXP SJA1105 E cmpliant 5-prt autmtive Ethernet switch TTTech DE Switch Hermes 3/1 BRR with 3 BradR-Reach physical layer interfaces and 1 x 1 Gbit/s prt BradR-Reach media cnverters BradR-Reach (100Base-T1) media cnverters are available frm: RAD-Mn Media Cnverter Technica Engineering Bradcm Media Cnverter Technica Engineering NXP Media Cnverter 1000Base-T1 media cnverters 1000Base-T1 media cnverters are available frm: Technica Engineering 1000Base-T1 Cnverter Autmtive Ethernet Test Requirements Testing Ethernet systems is required t ensure the prper functining and quality. This f curse als applies t BradR-Reach Autmtive Ethernet slutins as they are develped and deplyed. The BradR-Reach slutins include chips, sub-systems like ECUs and autmtive switches and eventually the fully assembled car. The testing will include functinal Ethernet testing and Ethernet perfrmance testing. Functinal Ethernet testing can cver many items and depends n the Device Under Test (DUT) and the applicatin. When the DUT is an autmtive switch the functinal Ethernet lab-testing during develpment and QA verificatin typically includes: Testing with unicast, multicast and bradcast frames. Test f MAC address learning VLAN capability verificatin: Testing with untagged frames, with frames with ne VLAN tag and with duble tagged frames. Testing with different VLAN pririties Stress testing: Testing with high traffic lad Testing with different frame sizes including undersized and versized frames. Testing with different IFG settings.

9 Fundamental Ethernet perfrmance testing f a DUT during develpment and QA verificatin includes verificatin f: Thrughput maximum data rate that can be transferred thrugh the DUT Latency time it takes t transfer data thrugh the DUT (als knwn as Frame Transfer Delay) Frame lss data frames lst during the transfer f data thrugh the DUT Jitter the variatin in delay f transferred data packets (als knwn as Frame Delay Variatin) Testing is in typically dne in accrdance with the IETF (Internet Engineering Task Frce) RFC 2544 Benchmarking Methdlgy fr Netwrk Intercnnect Devices, which specifies thrughput, latency and frame lss testing. Mst Ethernet testers als include jitter testing in their RFC 2544 test suite. Autmtive Ethernet netwrks include Layer 2 switches. T verify the crrect functining f these switches IETF has defined the RFC 2889 Benchmarking Methdlgy fr LAN Switching Devices in additin t RFC RFC 2889 prvides a methdlgy fr benchmarking switching devices, frwarding perfrmance, cngestin cntrl, latency plus address handling and filtering. Uplink prts n Autmtive Ethernet switches with BradR-Reach capabilities are typically implemented as 1 Gigabit/s Ethernet ptical r electrical prts. These prts als need t be tested t fully verify the functining f the switches. Xena Netwrks Autmtive Ethernet Slutins The Xena M6SFP 6-prt 1Gbps test mdule prvides pwerful testing capabilities t test and verify BradR-Reach autmtive Ethernet slutins. Figure 4: The pwerful and versatile Xena M6SFP 6-prt 1Gbps test mdule Testing up t Layer 3 Based n Xena s advanced architecture, the M6SFP is a prven slutin fr Ethernet testing at layers 2 and 3 up t 1 Gigabit/s. Advanced test scenaris can be perfrmed using the free test applicatins fr the M6SFP: XenaManager-2G test sftware is used t cnfigure and generate streams f Ethernet traffic between Xena test equipment and Devices Under Test (DUTs) and analyze the results.

10 Traffic generatin at line rate Flexible MAC address generatin Generatin f unicast, multicast and bradcast frames Generatin f frames withut VLAN tags, with ne VLAN tag and duble tagged frames Cnfigurable VLAN pririty Frame sizes frm 56 bytes (undersized) t bytes (versized) Adjustable Inter Frame Gap (IFG): Cnfigurable frm 16 t 56 bytes Xena2544 ffers full supprt fr the 4 test types specified in RFC 2544: Thrughput Latency Frame lss Back-t-back frames Jitter (Frame Delay Variatin) is als supprted Xena2889 is an applicatin fr benchmarking the perfrmance f Layer 2 LAN switches. The fllwing RFC 2889 test types are supprted: All Thrughput and Frwarding rate tests (bth Fully and Partially meshed) Cngestin Cntrl Address Caching Capacity Address Learning Rate Bradcast Frame Frwarding and Latency Frward Pressure and Maximum Frwarding Rate Xena3918 makes it easy t create, edit and execute all test types specified in RFC RFC 3918 describes tests fr measuring and reprting the thrughput, frwarding, latency and Internet Grup Management Prtcl (IGMP) grup membership characteristics f devices that supprt IP multicast prtcls. Xena1564 prvides full supprt fr bth the cnfiguratin and perfrmance test types described in Y.1564 fr cmplete validatin f Ethernet Service Level Agreements (SLAs) in a single test. The M6SFP can test up t 6 prts simultaneusly and in a 12 slt XenaBay chassis fully equipped with M6SFPs 72 prts are available fr testing. Testing frm 10 Megabit/s t 1 Gigabit/s The M6SFP supprts 10 Mbit/s, 100 Mbit/s and 1000 Mbit/s Ethernet testing n electrical interfaces and 100 Mbit/s and 1000 Mbit/s Ethernet testing n ptical interfaces depending n installed SFP mdules. This means that bth 100 Mbit/s prts and the uplink prts in Autmtive Ethernet switches can be tested with the M6SFP. The pwerful capability f Ethernet testing up t layer 3 at 100 Mbit/s and 1 Gigabit/s makes the M6SFP a versatile slutin fr perfrmance and functinal testing f Autmtive Ethernet BradR-Reach capable equipment.

11 Test Autmatin Autmtive Ethernet prducts require testing during develpment and prductin. In bth cases test scenaris are executed repeatedly t verify the quality and stability f the prducts. This is nrmally autmated t ensure unifrmity and reduce labr cst. XenaScripting is a pwerful and easy-t-use cmmand-line-interface (CLI) scripting API that makes test autmatin easier fr test engineers: Ideal fr test autmatin f e.g. prductin envirnments Cntrls XenaBay and XenaCmpact chassis with installed test mdules Pwerful CLI apprach frm any TCP/IP capable tl envirnment Unified syntax fr CLI- and GUI-generated test prt cnfiguratins makes it easy t learn Script examples f Tcl, Perl, Java, Ruby, BASH and Pythn available Intelligent cnsle tl bundled free with XenaManager-2G The XenaBay and XenaCmpact chassis are typically cntrlled using XenaManager-2G, the free GUI applicatin prvided by Xena Netwrks. Everything yu can d with XenaManager-2G can als be dne via XenaScripting, using simple CLI text cmmands. RFC 2544 and RFC 2889 testing can als be executed with CLI text cmmands. CONCLUSION The BradR-Reach 100 Mbit/s Autmtive Ethernet is a reality tday and grwing rapidly driven by the need fr ptimizatin f in-car cabling. BradR-Reach is based n 100 Mbit/s Ethernet running ver a single unshielded twisted pair cpper wire, which significantly reduces bth cst and weight f the cabling. Test f Autmtive Ethernet prducts is required t ensure the prper functining and quality. This includes testing in accrdance with RFC 2544 and RFC Fr develpment and prductin autmated tests are required t ensure unifrmity and reduce labr cst. With the Xena M6SFP 6-prt 1Gbps test mdule the user gets pwerful and versatile autmtive Ethernet test capabilities up t Layer 3 including RFC 2544 and RFC 2883 t test and verify BradR-Reach 100 Mbit/s autmtive Ethernet prducts. Bth 100 Mbit/s prts and uplink 1 Gigabit/s Ethernet prts in Autmtive Ethernet switches can be tested with the M6SFP. Cntrlling tests with XenaScripting adds repeated testing f the autmtive Ethernet prducts required in develpment and prductin.