Testing Considerations for Beyond 10Gigabit Ethernet. Erin Hallett

Transcription

1 Testing Considerations for Beyond 10Gigabit Ethernet Erin Hallett JDSU

2 Agenda Intro Need for Speed Growth of IP traffic Fiber vs. Copper Fiber Tightening requirements Testing considerations and practices Copper: past, present, and dfuture 10GBASE-T Cabling standards TR 42.7 update Field test requirements and challenges Conclusion Pro-active testing/certification t cat

3 INTRODUCTION Key Points: IP Traffic continues to grow exponentially Enterprise networks keeping up with demand Copper vs. Fiber: Is that the question?

4 Traffic Milestones and Generators

5 Enterprise Network Now and Future WAN/Internet Core Switching/Routing ti LAN 1/10/40GbE 1/10/40GbE Access Switching 1/10/40/100GbE Distribution/Aggregation Switching/Routing 100/1000M/10GbE 1/10/40GbE Access Switching 1/10/40/100 GbE WLAN Workspace Devices Servers Which links will be electrical? Which links will be optical? SAN SAN Switches 4/8/16M Fibrechannel Storage

6 Ethernet Electrical vs. Optical Timelines Fiber Copper

7 Copper vs. Fiber what is the path forward? Will fiber replace copper to the desktop? Will copper replace fiber for short runs in the DC? Copper Fiber Known and understood Newer/less understood Easy to install/terminate Easy for MACs PoE Backwards compatible to lower speeds Harder to install/terminate Port/conduit density Secure Longer runs Heat? Power?

8 FIBER Key Points: Key Points: Loss requirements are getting tighter Connector loss is critical and controllable Best practices for testing/certifying fiber are fairly well established

9 Application Specific Performance Requirements Cable Type Wavelength 1GbE 10GbE 40 /100GbE Loss (db) Length (m) Loss (db) Length (m) Loss (db) OM n/a n/a n/a n/a OM OM n/a n/a OM n/a n/a 1.5 n/a Length (m) n/a n/a 150 n/a Note: Ethernet standards limit 1GbE to 550 m and 10GbE to 300m. Some vendors allow greater distances

10 Generic Fiber Performance Requirements Slope Cable Type 850 nm 1300 nm 1310 nm 1550 nm OM1 3.5 db/km 1.5 db/km n/a n/a OM2 3.5 db/km 1.5 db/km n/a n/a OM3 35dB/km dB/km 1.5 n/a n/a OM4 3.5 db/km 1/5 db/km n/a n/a OS1 LAN n/a n/a 1.0 db/km 1.0dB/km OSP n/a n/a 0.5 db/km.05 db/km Max allowed loss per connector/splice.75 db per connector.3 db per splice How many connectors get you to db of loss?

11 Multi-Fiber Push-on/Pull-off (MPO) Used with breakout cassette Two connectors in short distance Or used direct (for 40/100G) Only 8 of 12 fibers used for 40G on 12 strand MPO Migration path in DC to 40/100G

12 Typical Enterprise Fiber Installation Duplex Fiber Patch Cord Fiber Pair between DC and TR Typically multiple pairs Duplex Fiber Patch Cord Router in Data Center Optical Patch Panel Optical Patch Panel Switch in Telecom Room Things to Consider: Application loss requirements are for the channel not the PL Use of MPO cassettes adds connections (and associated loss)

13 Fiber End-Face Condition Poor end-face condition creates excessive loss at connectors TIA-568 Annex E (new) calls on IEC IEC provides PASS/FAIL requirements for connector endface quality

14 Fiber End-Face Condition MPO cassettes add connections and associated loss One connector, multiple fiber end-faces troubleshooting nightmare in live network

15 Tier 1 Fiber Certification Length and Loss TIA generic limits provide basic pass/fail Increasing need to know what applications are supported Application-based pass/fail Length and overall loss

16 Tier 1 Fiber Certification Referencing Improper referencing leads to incorrect results What is the condition of the test jumpers? What is the right number of fibers to use when referencing? Never disconnect the TX after reference! Dealing with connector mis-matches (SC/LC) One Fiber Two Fiber Three Fiber Light Source Power Meter Fiber plant under Test Test Jumpers Test Jumpers Power Meter Light Source Connections included in results due to reference method

17 Tier 1 Fiber Certification Overall loss is more accurate than OTDR If done correctly! Testing MPO cables requires fan-out cable (today) Launch Conditions into MM CPR and Mandrels (yesterday) Encircled Flux (tomorrow) EF NOT OK EF Modal Controller EF Compliant Set-Up

18 Tier 2 Fiber Certification OTDR trace: shows the loss per event (connectors, etc) and overall slope loss. Pass/Fail per event. Event Loss Max 0.75dB Fiber Loss Slope 850 nm: 3.5 db/km 1300 nm: 1.5 db/km 1310/1550 nm : 1.0 db/km Event Loss Max 0.3dB

19 Tier 2 Fiber Certification Launch and Tail Launch cable needed to see first connector Launch cable length a function of attenuation dead zone, which is a function of pulsewidth Non-reflective tail needed to see last connector For MM, use a PC-APC jumper Condition of launch and tail jumper critical

20 Tier 2 Fiber Certification Condition of OTDR connector critical Two connectors close together may not both be seen (think MPO cassette)

21 COPPER: PAST, PRESENT, AND FUTURE Key Points: 10GBASE-T is finally taking off Cabling standards continue to evolve to support higher speeds Field testing must evolve to support new cabling standards

22 Evolution of Copper Cabling and Ethernet 40GBASE-T Soon? (Cat-7A)/Class FA 2009 Cat-6A/Class EA (Cat-7)/Class F Cat-6/Class E 10GBASE-T BASE-T 1999 Cat-5e BASE-TX Mhz 250Mhz 500Mhz 600Mhz 1000Mhz Level IIe Level III Level IIIe Level IV Tester Accuracy

23 Why Does Anyone Want 10GBASE-T? Backwards compatible with other BASE-T technologies Auto-negotiate Migration path vs. forklift upgrade Potentially cheaper than fiber Installation Maintenance Uses a well-known and understood media Category 6 UTP (55 meters) Category 6A UTP (100 meters) Power over Ethernet Wireless Access Points

24 Barriers to 10GBASE-T Adoption Introduced in 2006 it has been slow to catch on Power requirements Availability of network equipment and servers that support Field testing Recession did not help

25 Where is 10GBASE-T Today? Power budgets have gone from 10W to 4W and are expected to hit 2.5W in the next months Major network equipment vendors have added 10GBASE-T ports to their offerings Server adapters readily available and lower cost Energy efficient Ethernet has significantly lowered to power requirements and allowed a low-power mode In the data center 10GBASE-T will grow from only 4% of media in 2010 to 44% in 2013

26 Cabling Standards Today TIA-568 Category ISO Class Frequency Max Ethernet Speed Tester Accuracy Level Category 5e Class D 100 MHz 1000BASE-T Level IIe Category 6 Class E 250 MHz 10GBASE-T (1) Level III Category 6A Class EA 500 MHz 10GBASE-T Level IIIe Class F 600 MHz???? Level IV Class FA 1000 MHz???????? Note (1) Limited Distance

27 TIA TR 42.7 Next Gen Cabling February 2011: Approved Project to develop next gen cabling for copper data rates beyond 10G Expected to create a new category of cabling (twisted pair) including field test requirements Data center focus shorter runs for end-of-row environment Backwards compatible with RJ45 allows migration path from 1/10GbE Early view is such cabling would need to support 2000MHz of bandwidth!

28 Field Testing Bandwidth for 40G Over Copper 2400 Freq (M Hz) CAT5e CAT6 CAT6A CLASS F (CAT7) CLASS FA (CAT7A) Highest Test Frequency (MHz) today Possible Highest Test Freq (40G) Field testing bandwidth will be stretched more than two-folds!!

29 Key Technical Issues for 40G Over Copper Issue Data rate stretches Shannon Capacity of available cabling types Mitigation - Use higher bandwidth - Current discussions at TIA, ISO, and IEEE range from 1600 to 2000 MHz

30 Key Technical Issues for 40G Over Copper Issue PHY devices in the network cards become too hot trying to remove impairments in signal Mitigation Higher category cabling systems have far less impairments These cables may relieve some work of PHY devices and let them remain cooler

31 Key Technical Issues for 40G Over Copper Issue Insertion Loss at high frequencies degrade signal too much Mitigation This may require standards to specify shorter lengths than 100m Not a big issue for data centers because large proportions of links already less than 50m

32 Tester Bandwidth Challenge Field testing has been limited to lower frequencies BALUN raises noise floor, frequency limitation, poor temperature performance, required regular referencing Clock jitter Sampling rate limitations Unavailability of precision low cost wideband sources Newer designs have solved these problems Some field testers available today have the ability to test proposed frequencies

33 CONCLUSION Key Points: Pro-active testing ti is more critical than ever before Fiber end-face inspection is critical for fiber Field testing copper beyond 1GHz will be required

34 Pro-Active Testing of Infrastructure The need for speed continues unabated. Data centers and enterprise networks need to keep pace Now more than ever the physical media needs to be pro-actively tested t and certified Fiber end-face condition is the leading cause of excessive loss End-face inspection is critical MPO connectors are particularly critical Copper cables will soon exceed 1GHz field testing must keep up

35 Q&A