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Physical Infrastructure trends and evolving certification requirements for Datacenters Ravi Doddavaram www.psiberdata.com
Physical Infrastructure trends and evolving certification
requirements for Datacenters
Ravi Doddavaram
www.psiberdata.com
Agenda
• Market Trend and business case for higher speeds
• Benefits and Challenges in migration to new standards
• Limits on Physical infrastructure • Certification challenges for the new physical
layer infrastructure
• Market Trend and business case for higher speeds • Benefits and Challenges in migration to new
standards • Limits on Physical infrastructure • Certification challenges for the new physical layer
infrastructure
Market Trend and business case for higher speeds
Benefits and Challenges in migration to new standards
Limits on Physical infrastructure Certification challenges for the new physical
layer infrastructure
Moving towards Higher Speeds
Source: Psiber Data Pte Ltd
Demand Increased Users
Broadband, NBN penetration
Increased Access rates Multiple Access schemes, Wi Fi, FTTH, LTE
Increased Services Social Media explosion,
Content on Internet Massive data requirements due
to video traffic
Broadband, NBN penetration
Increased Access rates Multiple Access schemes Wi Fi
How are we getting there
Adoption Change in Data Center Topology LOM Integration of 10G, Cost benefits Upgrading existing standards IEEE 802.3 AD The TIA 942-A Standard Physical layer infrastructure upgrades tion Change in Data Center Topology LOM Integration of 10G, Cost benefits Upgrading existing standards IEEE 802.3 AD The TIA 942-A Standard Physical layer infrastructure upgrades
Access Topologies before 2010
Not Interesting
>1G (multiple standards)
<100 Mbps Gbps
Access Topologies
Still Not Interesting
40 Gbps (LOM) or LAG
10 Gbps(LOM)
Virtual NICs push bandwidth requirements on Servers/Access
Other Topologies (Fabrics)
Source: Jonathan Jew, J&M consultants
Why not existing standards?
IEEE 802.3 Ad (LAG) Supports L2 Link aggregation 4 x 10 Gbps links Independently managed channels Scalable Widely used ( due to unavailability of
alternative)
Disadvantages over IEEE 802.3ba (40Gbps) Slower networks, high latency
Especially for LAN/SAN convergence Higher cost of management due to port count Higher cost per port ( No LOM option) Load balancing is inefficient
Source: HSSG, IEEE 802.3 ba
TIA 942-A Standards update
Parameter TIA 942 TIA 942-A ISO/IEC 24764
Cabling (back bone and horizontal cabling)
CAT 3 to CAT6a OM1, OM2…OM4
CAT6, CAT6a OM3, OM4
ISO Class Ea OM3(min. requirement)
Length (HC) 100m for copper 300 m w/o HDA on Fiber
100m for copper Application specific length requirement (TIA 568 C.0)
100m for copper Channel restrictions OF-300 300m OF-500 500m
Connectors No requirement LC, MPO LC, MPO
Topology MDA->HDA->EDA MDA->IDA->HDA->EDA
MD->ZD->LDP
Source: Psiber Data Pte Ltd
Physical Layer Infrastructure
Fiber or Copper: Depends of the datacenter layout
End of Row (Cost efficient, SCS) Top of the Rack (Scalable Design, Large
Scale Datacenters)
Declining Cost of 10G BASE-T Depends on equipment connected
to Access layer Connected to PCs, other CPEs, Wi-Fi Connected to Servers
Flexible connections upto 4 connectors in a channel
Source: The Siemon Company
Physical Layer Infrastructure
Achieving 40 Gbps on Fiber Use of Parallel Optics through QSFP connectors and MPO arrays IEEE 40G BASE-SR4 Mostly Multi-mode preferred for Datacenter applications
TIA 942-A requires use of OM3 Fiber Needs 8 ports of the MPO array
Certification Issues in MPO
Polarity Issues Three types of MPO cords in the market Type A, Type B, Type C
Certifying to TIA/ISO 11801 standard puts a limit on number of connectors Insertion Loss/Connector specification Maximum permissible loss of 1.9 dB
Loss of 0.75 dB per connector makes only two connectors per link possible
The new IEC 14763-3 Ed 2.0 (2012) (yet to be ratified) Specifies 3 jumper reference as the default test method One jumper method only applicable for Permanent Links
Certification for Multimode (OM3) Fiber
Limiting Factors of OM3, OM4 Fiber Differential Modal Delay
Attenuation over long distances Attenuation still the primary certification metric OTDR is mostly for OSP (Outside Plant applications)
Encircled Flux Compliance
Required by ISO 11801- AMD2 document Requirement on Light source for Multimode certification Similar function as a mandrel but more precise using a
Mode-Conditioner Now TIA is also adopting it
What is Encircled Flux? Measurement of light coupled to a MM Fiber as a function
of offset from the core Measurement Sources need to fall into the EF template
Copper Infrastructure for High Speed
Achieving 40Gbps in copper Distance For < 7m Standard exists (CR4) (used within Racks) Evolving “CAT8” Standard.(>50m, capable of EoR)
2000 MHz
Bandwidth
Field Testing feasibility, is accuracy enough?
Upcoming CAT8 Standard Highlights of the standard Likely to be available by 2015 Will most likely use an RJ45 connector Supports 40m of 40GBASE-T Specified till 2GHz Primarily targeted at Datacenter markets with smaller channel length requirement Channel limits are already defined
RL about 6 dB at 2GHz Insertion Loss 54.4 dB at 2GHz NEXT (To be defined)
Please note that this is for information only, the standard is not ratified yet.
Certification Requirements
Frequency of Testing Should be capable of certifying cables up to 2GHz (at least)
Accuracy of Field Testing Accuracy should be specified till 2GHz Current document of IEC 61935-2 specifies 600 MHz
Draft of 1000 MHz in progress and to be ratified by 2014
Strong Correlation of all parameters like NEXT, RL with Lab. Instruments (such Testers are already available in the market)
Certification Requirements
Typical Return Loss measurement for 2GHz
Certification Requirements
Typical NEXT measurement for 2GHz
Field testing till 2GHz possible today Demonstrated accuracy with laboratory grade equipment
