Frame Error Rate. IEEE 802.3bj Task Force. September 24-26, 2012, Geneva, Switzerland. Roy Cideciyan IBM

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1 Frame Error Rate IEEE 802.3bj Task Force Setember 24-26, 2012, Geneva, Switzerland Roy Cideciyan

2 Introduction This resentation addresses 802.3bj Draft 1.1 comments 159, 258, 261 and bj is required to suort a bit error rate of 1e-12 or better at MAC/PLS service interface 32-bit Ethernet CRC in MAC frames rovides a mechanism to measure frame error rate (FER) in MAC layer MAC frames can vary in size between 64 octets and 2000 octets encoding is mandatory for 100GBASE-CR4, 100GBASE-KR4 and 100GBASE-KP4 In brown_3bj_02_0912 the roblem of determining FER is studied assuming indeendent bit errors in MAC layer Questions that need to be studied How does FER measured in MAC layer deend on required bit error rate (BER) at the MAC/PLS service interface? How does FER deend on the code? How does FER deend on modes of decoder oeration? Here a methodology to comute MAC frame error rate is roosed for required BER at MAC/PLS service interface Frame Error Rate 2

frames can vary in size between 64 octets and 2000 octets encoding is mandatory for 100GBASE-CR4, 100GBASE-KR4 and 100GBASE-KP4 In brown_3bj_02_0912 the roblem of determining FER is studied assuming

3 Assumtions Three modes of Reed-Solomon () decoder oeration are considered in order to evaluate the MAC frame error rate for a required bit error rate at MAC/PLS service interface Mode 1: decoder erforms error correction -FEC sublayer latency ~90ns Mode 2: decoder erforms only error detection rior to releasing data -FEC sublayer latency ~50ns Mode 3: decoder erforms only error detection in trailing mode -FEC sublayer latency ~5ns 3x error multilication due to self-sync descrambler in hysical coding sublayer (PCS) Inverse transcoding does not have an imact on error rate Indeendent bit errors at decoder inut Frame Error Rate 3

data -FEC sublayer latency ~50ns Mode 3: decoder erforms only error detection in trailing mode -FEC sublayer latency ~5ns 3x error multilication due to

4 Methodology to Comute FER Mode 1 Mode 2 Mode 3 brown_3bj_02_0912 UCR PLS MAC FER? Ch s,ch Decoder Inverse Transcoder Self-sync Descrambler CRC Checker MAC 1e-12 PLS: Physical Layer Service MAC: Medium Access Control MAC : Bit error rate at PLS/MAC interface : Bit error rate at decoder outut Ch : Bit error rate at decoder inut s,ch : Symbol error rate at decoder inut UCR: Uncorrectable Codeword Ratio FER: Frame Error Rate CRC: Cyclic Redundancy Check Frame Error Rate 4

Medium Access Control MAC : Bit error rate at PLS/MAC interface : Bit error rate at decoder outut Ch : Bit error rate

5 Mode 1 NBF: Number of octets er MAC frame NBC: Number of octets er codeword (n,k) code with error correction caability t and symbol size m 100GBASE-KR4 and 100GBASE-CR4 emloy (528,514), t7 and m10 code 100GBASE-KP4 emloys (544,514), t15 and m10 code UCR FER 2 2 MAC m n 3 i t+ 1 m 1 1 UCR n i n i t i n i s, Ch n i ( 1 ) NBF NBC i s, Ch s, Ch ( 1 ) n i s, Ch n i s, Ch b, 3 Comute such that 1 12 e Relationshi between FER and UCR derived in brown_3bj_02_0912 Frame Error Rate 5

m10 code UCR FER 2 2 MAC m n 3 i t+ 1 m 1 1 UCR n i n i t+ 1 1 + i n i s, Ch n i ( 1 ) NBF NBC i s, Ch s, Ch ( 1 ) n i

6 Mode 2 and Mode 3 In Mode 2 errors in codeword can be detected rior to releasing data. MAC/PLS interface is aware of errors that have occurred. 3 UCR 1 MAC FER UCR ( 1 ) 1 + nm NBF NBC In Mode 3 errors in codeword can only be detected in trailing mode. MAC/PLS interface is not aware of errors that have occurred. FER 3 1 MAC 8 ( 1 ) NBF Frame Error Rate 6

3 UCR 1 MAC FER UCR ( 1 ) 1 + nm NBF NBC In Mode 3 errors in codeword can only be

7 Frame Error Rate Mode 1, NRZ Mode 2, NRZ Mode 3, NRZ Mode 1, PAM4 Mode 2, PAM4 Mode 3, PAM4 MAC 1e-12 Frame Error Rate 10-9 Yellow and green curves are on to of each other Number of octets er MAC frame Frame Error Rate 7

and green curves are on to of each other 10-10 10-11 0 200 400 600 800

8 Frame Error Rate for 800-Octet Frames NBF 800 FER NRZ PAM4 MAC 1e-12 Mode 1 1.3e-10 6e-11 Mode 2 4.5e-9 4.6e-9 Mode 3 2.1e-9 2.1e-9 Two extreme cases If bit errors at MAC/PLS interface are uncorrelated as assumed in brown_3bj_01_0912, then FER ( 1 1e 12 ) e e 9 If bit errors at MAC/PLS interface are highly correlated, i.e., bits in a frame are either all correct or all wrong, then FER 1e 12 Frame Error Rate 8

1e-9 Two extreme cases If bit errors at MAC/PLS interface are uncorrelated as assumed in brown_3bj_01_0912,

9 Summary Presented a methodology to comute frame error rate for required bit error rate at MAC/PLS service interface Frame error rate is a function of MAC frame size in octets Modes of decoder oeration Signaling scheme used For 800-octet MAC frames and a required bit error rate of 1e-12 at MAC/PLS service interface, the frame error rate varies between 6e-11 and 4.6e-9 Frame Error Rate 9

decoder oeration Signaling scheme used For 800-octet MAC frames and a required bit error rate of

10 Thank You Frame Error Rate 10

100GBASE-KP4 EEE synchronization and signaling. Comments #234 and #235

100GBASE-KP4 EEE synchronization and signaling Comments #234 and #235 IEEE P802.3bj July 2012, San Diego Matt Brown AppliedMicro Adee Ran Intel Kent Lusted -- Intel Introduction Addresses comments #234