Core Network Evolution and IPoDWDM: 40G 100G and Beyond Stefan Kollar Consulting Systems Engineer CCIE #10668

Transcription

1 Core Network Evolution and IPoDWDM: 40G 100G and Beyond Stefan Kollar Consulting Systems Engineer CCIE # Cisco and/or its affiliates. All rights reserved. 1

2 OTN Technical Foundation OTN Properties and Impact on IP Layer MPLS-TP Technical Foundation MPLS-TP Forwarding and OAM MPLS-TP Deployments 40G/100G Design Considerations 40G/100G Deployment Considerations in 10G Optical Networks 100G - and beyond 2010 Cisco and/or its affiliates. All rights reserved. 2

3 Global IP Traffic Growth IP traffic will increase fivefold from IP packets will Dominate 87% Consumer Traffic Video IP Routed Services L2 Packet Services Other Services SONET/SDH Data Centre Private Line 2010 Cisco and/or its affiliates. All rights reserved. Source: Cisco Visual Networking Index Forecast,

4 OTN Technical Foundation Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 4

5 OTN defined a fixed hierarchy of payloads: from OTU1 (2.5G) to OTU3 (40G). Now ODU0 (1G) and OTU4 (100G) are being added OTN started as a pure wrapper around WDM client signals to improve reach and manageability Recently it has developed into a complex multiplexing structure that enables a service layer as well as TDM bandwidth mgmt Frame ODU0 (coming) OTU1 OTU2 OTU3 OTU4 (coming) Payload (OPU) 1,238,954 kbit/s 2,488,320 kbit/s 9,995,276 kbit/s 40,150,519 kbit/s 104,355,975 kbit/s 2010 Cisco and/or its affiliates. All rights reserved. 5

6 2010 Cisco and/or its affiliates. All rights reserved. 6

7 The OTN Multiplexing Hierarchy OTN Hierarchy ODU0: ~1.22Gbps : GE ODU1: ~ 2.7Gbps : STM-16 ODU2 : ~10.7Gbps : STM-64 ODU3 : ~43Gbps : STM-256 ODU4: ~112Gbps : 100GE ODU2e:~11.1Gbps : 10GE LAN PHY ODU3e:~40Gbps : 10GE onto 40G ODU-FLEX Similar concept to VCATs in SONET/SDH but uses OTN containers Increments are variable (10Gbps, 1Gbps) but only one increment size per link 1.25Gbps increments is the most commonly discussed ODU-FLEX service. ODU-FLEX Switch TS TS TS TS ODU-FLEX Switch Client Classifier GFP GFP GFP GFP + idles ODU-FLEX GMP TS TS TS TS TS TS GMP ODU-FLEX GMP TS TS TS TS TS TS ODU-FLEX GMP GFP GFP GFP GFP + idles Client HO ODU HO ODU HO ODU HO ODU 2010 Cisco and/or its affiliates. All rights reserved. GMP stands for the Generic Mapping Procedure that is currently under definition in Q11 7

8 Sub-lambda HO interfaces (SONET, OTN, Ethernet, ESCON) OTN HO Electrical Cross Connect Grooming and aggregation Ethernet Switching Fabric G.709 formatted signal, OTUm Ethernet interfaces (e.g. OC-3/STM-1) OADM / Mesh DWDM node Multi-degree ROADM Cross Connecting Lambdas Dropping full lambdas Supported Ethernet Service Types per G.8011.x Point-to-Point Ethernet Private Line (EPL) Type 1 Ethernet Private Line (EPL) Type 2 Ethernet Private Line (EPL) Type 2 timing transparent Ethernet Virtual Private Line (EVPL) Type 1, 2, 3 Supported Ethernet Service Types per G.8011.x Point-to-Multipoint Ethernet Private Tree (EPT) Ethernet Private LAN (EPLAN) Ethernet Virtual Private Tree (EVPT), Type 1, 2, 3 Ethernet Virtual Private LAN (EVPLAN), Type 1, 2, Cisco and/or its affiliates. All rights reserved. 8

9 OTN Properties and Impact on IP Layer Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 9

10 OTN OEO OTN OOO OTN OEO Encapsulation and OAM&P over optical spans (G.709 transponders) OTN OEO OTN OOO OTN OEO Point to Point Multiplexing (G.709 muxponders) OTN OEO OTN OOO OTN OEO OTN OEO OTN Grooming and Switching (OEO Cross Connects) OTN OEO 2010 Cisco and/or its affiliates. All rights reserved. 10

11 Individual IFs Works Cost Channelized POS/OTN No chotn Cost Ethernet w/ VLANs Shaping Metrics 2010 Cisco and/or its affiliates. All rights reserved. 11

12 Primary Optical Path Back Optical Path Primary Path failure Characteristics Optical level over-provisioning : 100% IP level over-provisioning : 0% Overall over-provisioning : 100% Complexity : High need hold timers Complete IP level protection: No Span Failure IP working : Yes Primary Optical Path Patch Cord, transponder or router card failure IP working : No Back Optical Path 2010 Cisco and/or its affiliates. All rights reserved. 12

13 The Contrasting Topologies Hierarchical Solution Physical and Logical Topology the same Video and Internet cache IP/TV Head End Internet Internet End User Business Data Centre L3 Routing Nodes Bypass Solution Video and Internet cache IP/TV Head End Business Data Centre Internet Internet End User Business Data Centre 2010 Cisco and/or its affiliates. All rights reserved. OTN ODU-FLEX switch Business Data 13 Centre

14 What s the Impact at the Network Level? Links and Over Provisioning 1Gbps Initial Demand 10Gbps increments Link Level Over provisioning 1Gbps Initial Demand 1Gbps increments Link Level Over Provisioning Network Efficiency and provisioning needs to account for total number of links, traffic growth, provisioning efficiency and upgrade frequency. OTN Technical Foundation Network Wide Implications 100 Node network Worse over-provisioning : Links * b/w increment Network wide link upgrades = Links * Link upgrades Worse case over-provisioning =200 * 10Gbps = 2000Gbps Number network wide physical link upgrades = 200 * 0 = Cisco and/or its affiliates. All rights reserved. Network Wide Implications 100 Node network Worse over-provisioning : Links * b/w increment Network wide link upgrades = Links * Link upgrades Worse case over-provisioning =5000 * 1Gbps = 5000Gbps Number network wide logical link upgrades = 5000 * 7 = Note : This does not take into account physical link upgrades 14

15 Photonics Bypass Client to OEO with SR optics Transport OTN OEO Approach Client with SR Optics Photonic Client with Integrated Optics Optical Approach Major IP demands are very large often the driving force behind DWDM upgrades Full interfaces directly to the photonic layer of NG/ROADM Intelligent DWDM system Cut-through / bypass at the photonics layer 2010 Cisco and/or its affiliates. All rights reserved. Transponder Short Reach Eliminates expensive high bandwidth opti-electrical components Optical More pronounced and in particular with 40Gbps and IPoDWDM 100Gbps is the most cost effective high b/w inter router connection 15

16 MPLS-TP Technical Foundation Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 16

17 Evolution of SONET/SDH transport networks to packet switching driven by Growth in packet-based services (L2/L3 VPN, IPTV, VoIP, etc) Desire for bandwidth/qos flexibility New packet transport networks need to retain same operational model An MPLS transport profile being defined at IETF (in collaboration with ITU-T) 2010 Cisco and/or its affiliates. All rights reserved. 17

18 IETF and ITU-T agreed to work together and bring transport requirements into the IETF and extend IETF MPLS forwarding, OAM, survivability, network management, and control plane protocols to meet those requirements through the IETF Standards Process.[RFC5317] 1 ITU-T withdrawal of T-MPLS draft G.8114 in Jan Definition of MPLS Transport Profile (MPLS-TP) protocols, based on ITU-T requirements Note: IETF decided to support single MPLS-TP OAM solution. IETF Chair stated at IETF 79 (11/2010) and IETF 80 (3/2011) Derive packet transport requirements Integration of IETF MPLS-TP definition into transport network recommendations 1: [RFC 5317]: Joint Working Team (JWT) Report on MPLS Architectural Considerations for a Transport Profile, Feb Cisco and/or its affiliates. All rights reserved

19 MPLS Solution Space ECMP MP2Pt LDP, IP MPLS-TP Solution Space PHP default disabled MPLS-TP Only Solution Space MPLS-TP is proper subset of MPLS proper So far, no MPLS-TP only functionality standardized 2010 Cisco and/or its affiliates. All rights reserved. 19

20 Connection-oriented packet switching model No modifications to MPLS data plane Interoperates/interworks with existing MPLS and pseudowire control and data planes No LSP merging or PHP LSPs may be point to point (unidirectional, co-routed bidirectional or associated bidirectional) LSPs may be point to multipoint (unidirectional) Networks created and maintained using static provisioning or a dynamic control plane: LDP for PWs and RSVP-TE (GMPLS) for LSPs In-band OAM (fate sharing) Protection options: 1:1, 1+1 and 1:N Network operation similar to existing transport networks See RFC Cisco and/or its affiliates. All rights reserved. 20

21 MPLS-TP Forwarding Plane Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 21

22 Static Bidirectional Co-routed (same forward and reverse paths) In-band Generic Associated Channel (G-ACh) Ultimate hop popping (no explicit/implicit null) No ECMP Contained within a tunnel G-ACh MPLS-TP LSP MPLS-TP Tunnel 2010 Cisco and/or its affiliates. All rights reserved. 22

23 No IP routing required in control and forwarding planes MPLS-TP Node will still source/terminate IP packets (e.g. SNMP, NTP) Link numbers required on each MPLS-TP interface Two interface configuration models IP-enabled (uses ARP) IP-less (no ARP) IP-enabled requires interface configuration for Local IPv4 address Remote IPv4 (next-hop) address IP-less requires configuration of Destination MAC address Same OAM messages for IP-enabled and IP-less interface configurations 2010 Cisco and/or its affiliates. All rights reserved. 23

24 MPLS-TP tunnels abstracted as Tunnel-tp interface Tunnel holds a working LSP and a protected LSP Working Protect (optional) Tunnel may be configured with a bandwidth allocation Tunnel operationally UP if at least one LSP operationally UP (and not locked out) Working LSP Protect LSP MPLS-TP Tunnel LSP operationally UP if OAM (Continuity Check) session operationally UP G-ACh G-ACh LSP requires static configuration of LSP label imposition (output label and output link) LSP requires static configuration of LSP label disposition (input label) LSP must be co-routed (no embedded check) 2010 Cisco and/or its affiliates. All rights reserved. 24

25 Same OAM functions for LSPs, pseudowires and sections In-band OAM packets (fate sharing) OAM functions can operate on an MPLS-TP network without a control plane Extensible framework with current standardization focus on fault and performance management Independent of underlying technology Independent of PW emulated service 2010 Cisco and/or its affiliates. All rights reserved. 25

26 IETF Label PW Label ACH OAM Payload Version Reserved Channel Type RFC 5085 PW Associated Channel Header (ACH) G-ACh PW G-ACh LSP Label GAL ACH OAM Payload RFC 5586 Generic Associated Channel Label (GAL) Associated Channel Header OAM capabilities extended using a generic associated channel (G-ACh) based on RFC 5085 (VCCV) A G-ACh Label (GAL) acts as exception mechanism to identify maintenance packets GAL not required for pseudowires (first nibble as exception mechanism) G-ACh used to implement FCAPS (OAM, automatic protection switching (APS), signaling communication channel, management communication channel, etc) 2010 Cisco and/or its affiliates. All rights reserved. 26

27 Before Failure Working LSP (Up, Active) PE1 Protect LSP (Up, Standby) During Failure Working LSP (Down, Standby) PE1 Protect LSP (Up, Active) P1 P2 P1 P2 Working LSP (Up, Active) PE2 Protect LSP (Up, Standby) Working LSP (Down, Standby) PE2 Protect LSP (Up, Active) Relies on a disjoint working and a disjoint protect path between two nodes Provides 1:1 protection (only one active LSP) in revertive mode Functionally similar to path protection in IP/MPLS Protection switching can be triggered by Detected defect condition (AIS/LDI, LKR) Administrative action (lockout) Far end request (lockout) Server layer defect indication (LOS) Revertive timer (wait-to-restore) 2010 Cisco and/or its affiliates. All rights reserved. 27

28 IETF Function Description Tool Continuity Check Checks ability to receive traffic BFD Connectivity Verification Verifies that a packet reaches expected node BFD (proactive) LSP Ping (on-demand) Diagnostic Tests General diagnostic tests (e.g. looping traffic) New Route Tracing Discovery of intermediate and end points LSP Ping Lock Instruct Instruct remote MEPs to lock path (only test/oam traffic allowed) New Lock Reporting Report a server-layer lock to a client-layer MEP New Alarm Reporting Report a server-layer fault to a client-layer MEP New Remote Defect Indication Client Failure Indication Packet Loss Measurement Packet Delay Measurement Report fault to remote MEP Client failure notification between MEPs Ratio of packets not received to packets sent One-way / two-way delay (first bit sent to last bit received) BFD PW Status New New 2010 Cisco and/or its affiliates. All rights reserved. 28

29 MPLS-TP deployements Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 29

30 Flexible Edge and Services Architecture Static MPLS-TP Access Aggregation! Edge! Multiservice Core! Core! Ethernet Access IP/MPLS Access (L2 and CE only) IP/MPLS + Dynamic MPLS-TP IP/MPLS IP/MPLS Pseudo-Wire Switching MPLS-TP IP/MPLS L3 IP Edge and Service Placement Circuit Emulation + Ethernet Flexible IP Edge and Service Placement Agg, Edge or Core IP/MPLS in Core / Edge / Aggregation Use MPLS-TP toolbox to enhance dynamic IP/MPLS domain Variety of Access options static MPLS-TP, Ethernet, IP/MPLS Common protocols and control plane aggregation to aggregation 2010 Cisco and/or its affiliates. All rights reserved. 30

31 Centralised Edge and Transport Architecture MPLS-TP Access Aggregation! Edge! Multiservice Core! Core! Ethernet Access IP/MPLS Access (L2 and CE only) IP/MPLS (L2 and CE only) IP/MPLS IP/MPLS Circuit Emulation + Ethernet L3 IP + Services Placement Centralised IP Edge and Service placement : Edge, Core IP/MPLS in Core / Edge / Aggregation Variety of Access options static MPLS-TP, Ethernet, IP/MPLS Common protocols and control plane aggregation to aggregation Ethernet Access / IP/MPLS L2 Aggregation : Widely deployed model 2010 Cisco and/or its affiliates. All rights reserved. 31

32 Centralised Edge and Transport Architecture Static MPLS-TP Access Aggregation! Edge! Core! Ethernet Access Static MPLS-TP IP/MPLS IP/MPLS Circuit Emulation + Ethernet L3 IP + Services Placement Centralised IP Edge and Service placement - Edge, Core IP/MPLS in Core / Edge Static MPLS-TP in Aggregation Variety of Access options : Ethernet / Static MPLS-TP Common forwarding protocols aggregation to aggregation End to end transport operations using pseudo-wire switching 2010 Cisco and/or its affiliates. All rights reserved. 32

33 40G/100G Design Considerations Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 33

34 Solutions for Implementing 100G DWDM 100G lambda 100G SR 100G lambdas OTN OTN 10G lambda 10G and 100G DWDM Coexistence 10G and 100G lambdas co-exist on same fibre Packet uses 100G, everything else 10G 10G SR OTN Multiplexing All lambdas upgraded to 100Gbps Sub-100G services provided by OTN OEO Advantages Only high demand clients upgraded to 100G Protects existing 10G DWDM investment Lowest cost per bit (100G TXPs>10 x10g TXPs) Advantages All lambdas on a fibre are 100G Disadvantages Need a guard band between 10G and 100G frequencies Not appealing in ULH environments Disadvantages 100TXP investment upfront Need an additional OTN OEO All 10G TXPs are obsolete 2010 Cisco and/or its affiliates. All rights reserved. 34

35 40 Gig and above rates must meet minimum requirements: Target 10 Gig distances 1500 Km reach Not simply a Greenfield technology, but plug and play over existing 10Gig networks Must be as open as possible, operate over third party DWDM networks Must operate over both 100GHz as well as 50GHz spacings Power and footprint must be reasonable, can not redesign Router/ transport shelf due to blade To achieve must leverage/control: 1. Optical Impairments 2. Modulations schemes 2010 Cisco and/or its affiliates. All rights reserved. 35

36 Attenuation Loss of signal strength Limits transmission distance Chromatic Dispersion (CD) Distortion of pulses Limits transmission distance Proportional to bit rate Optical Signal to Noise Ratio (OSNR) Effect of noise in transmission Caused by amplifier Limits number of amplifier 2010 Cisco and/or its affiliates. All rights reserved. 36

37 Polarization Mode Dispersion (PMD) Caused by nonlinearity of fiber geometry Effective for higher bit rates (10G) Spreaded Pulse as It Leaves the Fiber Four Wave Mixing (FWM) Effects in multichannel systems Effects for higher bit rates Self/Cross Phase Modulation (SPM, XPM) Effected by high channel power Effected by neighbor channels 2010 Cisco and/or its affiliates. All rights reserved. 37

38 Cisco expects 100G Deployments to: Target 10G distances Km reach Plug-and-play over existing 10Gig networks Must be spectrally efficient- 50GHz Grid Power / density / cost / performance trade off As Bit Rate increases the above becomes more challenging Simplify deployment of 100Gig into 10Gig Systems 2010 Cisco and/or its affiliates. All rights reserved. 38

39 Transmitter Decrease Speed reduce $$ Increase Modulation - Increase spectral efficiency Increase Optical efficiency Increase spectral efficiency Receiver Move from Direct Detection to Coherent detection Compensate for Optical impairments in Electrical Domain(DSP) reduce $$ Forward Error Correction (FEC) Move to Higher coding gain FECs Increase reach 100Gig was our first challenge overcame with PM-QPSK and new FECs 2010 Cisco and/or its affiliates. All rights reserved. 39

40 Need to go slower Optical impairments are directly related to signaling rates Need to increase modulation efficiency Signaling speed decreases & Information Rate increases NRZ to ODB to (D)PSK to (D)QPSK Need to increase optical efficiency Split signal over two polarizations (PM Mod Scheme) 1 bit/symbol 1 bit/symbol 2 bits/symbol NRZ PSK QPSK 2010 Cisco and/or its affiliates. All rights reserved. 40

41 RX Laser behaves as Local Oscillator to provide a Polarization reference 90 Hybrid: Converts Phase modulation in Amplitude modulation Signal Processor: Recovers Polarization Compensates CD and PMD electronically 2010 Cisco and/or its affiliates. All rights reserved. 41

42 100G PM-QPSK At and / or exceeds 10Gig System Performance Utilizing Cisco s advanced Optics and FEC Distances up to 2000Km and beyond Operates over existing Infrastructure at both 50 / 100GHz PM-QPSK allows 100G operation over existing and greenfield networks at 10Gig distances 2010 Cisco and/or its affiliates. All rights reserved. 42

43 40G/100G Deployment Considerations in 10G Optical Networks Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 43

44 3 rd PARTY DWDM SYSTEM MUST SUPPORT ALIEN WAVELENGTHS! Alien/foreign wavelength is any 3rd party ITU wavelength operating over an existing DWDM infrastructure. G698.2 Standard for Alien/Foreign waves defines: properties for signal sources and sinks properties for DWDM links for black links (i.e. alien wavelengths) 2010 Cisco and/or its affiliates. All rights reserved. 44

45 Design Considerations Noise and Impairment Limits 40G receiver differs from 10G Launch Powers 40G IPoDWDM Transponder (DPSK+) 10G Transponder 0 dbm 0 dbm Rx Windows 5 to 18 dbm 0 to 23 dbm OSNR (.1nm) ~ 14.5 db ~ 15 db CD +/- 750ps/nm +/- 2000ps/nm PMD 2.5ps 10ps 2010 Cisco and/or its affiliates. All rights reserved. 45

46 One of the biggest challengers in Poland (~350k broadband users) Implemented XR12000 core 1.5 year ago (one of the first XR12000 production networks in the world) BB explosion has made their traffic grow quicker than expected => need to upgrade main nodes Customer A expected big CapEx/OpEx savings 2010 Cisco and/or its affiliates. All rights reserved. 46

47 IPoDWDM CapEx/OpEx reduction Eliminates Transponder Shelf 4:1 Capacity Savings Conducted successful tests on 40G IPoDWDM on Warsaw -> Poznań link (614 km) link designed for 10G optical 2010 Cisco and/or its affiliates. All rights reserved. 47

48 100G Where are we today? Presentation_ID 2010 Cisco and/or its affiliates. All rights reserved. Cisco Public 48

49 IEEE 802.3ba: 40Gb/s and 100Gb/s Ethernet Task Force 40G and 100G Ethernet Physical interfaces for Backplane, Copper, Fiber PMDs IEEE 802.3bg: 40Gb/s SMF Ethernet Task Force 40G Serial PMD optimized for carrier applications ITU Study Group 15: Optical and Transport Networks OTU4 frame format Ratified Ratified Ratified Single mapping for 40GE/100GE into OTU3/OTU4 OTL protocol enabling OTU3/4 over multi-lane (low cost) optics OIF: 100G Long-distance DWDM Transmission Ratified Industry consolidation around a single 100G DWDM solution 2010 Cisco and/or its affiliates. All rights reserved. 49

50 Customer demands are driving the need for 100Gig and beyond Video HD / 3D Video Conferencing HD / 3D Gaming HD / 3D Packet will dominate 28% of population connected 14% of population broadband 100Gig is deploying NOW Content Providers Tier One SPs and MSOs Mass deployments 2 nd Half 2012 early 2013 Question is not When 100Gig? but rather What is after 100Gig? 2010 Cisco and/or its affiliates. All rights reserved. 50

51 Higher data rates 200Gig, 400Gig, 1T? Need to investigate other modulation techniques PM-16QAM, PM-64QAM,. or CO-OFDM? Need deeper look at FEC Advanced FEC What other algorithms are there Need of intelligent DWDM layer Flex spectrum Control plane Advanced operations, troubleshooting and protection mechanisms Must a channel really fit into 50GHz spacing? Or should it be gridless? 2010 Cisco and/or its affiliates. All rights reserved. 51

52 Information distributed over a few Sub-Carriers spaced as closely as possible forming a 1,000Gbps Super-Channel Each Sub-Carrier transporting a lower Bit Rate, compatible with current ADCs and DSPs Sch(f) 2 Super-Channel #1 Super-Channel #2 Super-Channel # f [GHz] 10x 100Gbit/s Sub- Carriers close-to-baud-rate spaced 2010 Cisco and/or its affiliates. All rights reserved. 52

53 Sub-Carrier spacing: 1.2 times the Baud Rate Different approaches for 1,000Gb/s: CP-QPSK: 10 Sub-Carriers at 111 Gbit/s each back-to-back sensitivity 12 db CP-8QAM: 8 Sub-Carriers at Gbit/ s each back-to-back sensitivity 16.1 db CP-16QAQM: 5 Sub-Carriers at 222 Gbit/s each back-to-back sensitivity 19.1 db System Configuration: Span of 90km each (ITU-T G.652) Span Insertion Loss: 25dB CP-QPSK CP-8QAM with subcarrier spacings 1.12 CP-16QAM Cisco and/or its affiliates. All rights reserved. 53

54 Thank you.