Next generation transport network - Carrier Ethernet Mobile Backhaul / Consumer Broadband / Enterprise Services

Transcription

1 Next generation transport network - Carrier Ethernet Mobile Backhaul / Consumer Broadband / Enterprise Services Ramakrishnan Subramanian Cisco Systems

2 Agenda Evolution and Trends in Mobile s Mobile Backhaul with Unified MPLS Unified MPLS introduction and architectures 2G/3G, LTE Backhaul Services Synchronization Fast Convergence Consumer Broadband Services Enterprise Services Summary

3 Backhaul Challenges Support of Multi-Technology over Transport. Mobile (2G, 3G, LTE), Enterprise, Consumer Services SDH based network is having lack of scalability for growing BW needs with low Capex. High Cost of backhaul Large Scale Fast Convergence Quality of Service Frequency Synchronization and Phase Synchronization Backhaul capacity is limiting the growth/expansion 2011 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 3

4 Service Category Bandwidth per 2G BTS Larger Cities 2-4 E1. Smaller Town: 1 2 E1 3G NB Voice: 1 E1 Data: 42MB in Large City 14-20MB in smaller Town 4G / LTE enb 100Mbps SP Wifi AP 4MB Consumer Broadband Enterprise Service Microwave DSLAM / OLT WiMax Hybrid Backhaul 1G / 10G 7MB Per Sector. No. of Sector: 3 to 4 Per Location Vary from 25 or 50 or 400Mbps

5 Mobile Backhaul with Unified MPLS

6 Unified MPLS classical MPLS with a few additions Classical MPLS IGP/LDP Domain isolation RFC 3107 BGP filtering Flex L2/IGP/BGP/MPLS- TP/LDP DoD LFA R-LFA BGP PIC E2E OAM Unified MPLS Architecture Scalability Security Simplification Multi-Service

7 Routing + MPLS Design Divide & Conquer Game Plan Disconnect & Isolate IGP domains No more end-to-end IGP view Leverage BGP for infrastructure (i.e. PE) routes Also for infrastructure (i.e. PE) labels (e.g. RFC3107) BGP for Services (e.g. L2, L3) BGP for Infrastructure Prefixes Isolated IGP & LDP Isolated IGP & LDP Isolated IGP & LDP Aggregation Region1. Backbone Region 2 Aggregation PE11 ISIS Level 1 Or OSPF Area Y. PE21 BGP (+Label) ISIS Level 2 Or OSPF Area 0 BGP (+Label).. ISIS Level 1 Or OSPF Area X PE21 R PE31

8 Unified MPLS Architecture (RFC 3107) IGP/LDP Label BGP3107 Label Service Label U-MPLS Classical MPLS Pre-Aggregation ibgp/ebgp Aggregation Aggregation EPC Gateway Core Centralised RR IGP/LDP IGP/LDP IGP/LDP

9 Sample E2E Unified MPLS Architecture Routing Isolation and Label Stack for LSP between Pre-Agg. Loopbacks L2 IGP/LDP Label Pre-Agg. Push Aggregation Agg. ISIS Level 1/OSPF x Agg. Core MPC Gateway ISIS Level 2/OSPF 0 Centralised RR Swap Pop Push Swap Pop Aggregation Agg. ISIS Level 1/OSPF x Agg. Pre-Agg. L2 BGP3107 Label Push Swap Swap Swap Pop Service Label LDP LSP LDP LSP LDP LSP BGP LSP No IGP route is propagated from Aggregation to the Core. IGP area has routes for that area only plus routes to core ABRs. Only the core ABR s are propagated from L2 to L1 LDP labels are used to traverse each domain and reach core ABRs BGP labels are used by Labeled BGP PEs & ABRs to reach Labeled BGP PEs in remote areas Service (e.g. PW) labels are used by Label BGP PEs

10 Unified MPLS Model 1 MPLS support in the Core, Aggregation with TDM, uwave or L2 in the access Pre-Agg. Aggregation Agg. Core MPC Gateway Aggregation Agg. Pre-Agg. L2 Agg. Centralised RR Agg. L2/TDM/uWave LDP LSP LDP LSP ibgp Hierarchical LSP LDP LSP L2/TDM/uWave The Mobile Core and Aggregation s enable Unified MPLS Transport The Core and Aggregation s are organized as independent IGP/LDP domains The network domains are interconnected with hierarchical LSPs based on RFC 3107, BGP IPv4+labels. Intra domain connectivity is based on LDP LSPs The Aggregation enable Mobile and Wire line Services. The Mobile RAN is based on TDM, Packet Microwave or pt-to-pt L2 connectivity

11 Unified MPLS Model 2 MPLS support in the Core, Aggregation and Pre-Agg. Aggregation Agg. Core MPC Gateway Aggregation Agg. Pre-Agg. LDP LSP Agg. LDP LSP Centralised RR LDP LSP Agg. LDP LSP LDP LSP ibgp Hierarchical LSP The Mobile Core, Aggregation, enable Unified MPLS Transport The Core, Aggregation, are organized as independent IGP/LDP domains The network domains are interconnected with hierarchical LSPs based on RFC 3107, BGP IPv4+labels. Intra domain connectivity is based on LDP LSPs The s learn only the required labelled BGP FECs, with selective distribution of the MPC and potentially neighbouring RAN labelled BGP communities

12 Unified MPLS Model 3 MPLS in the Core, Aggregation with IGP/LDP in the access Pre-Agg. Redistribute MPC ibgp community into RAN IGP Aggregation Agg. Core MPC Gateway Aggregation Agg. Pre-Agg. Redistribute CSN Loopbacks into ibgp LDP LSP Agg. LDP LSP Centralised RR LDP LSP ibgp Hierarchical LSP Agg. LDP LSP LDP LSP The Core and Aggregation are organized as distinct IGP/LDP domains Inter domain hierarchical LSPs based on RFC 3107, BGP IPv4+labels which are extended out to the Preaggregation Intra domain LSPs based on LDP The inter domain Core/Aggregation LSPs are extended in the s by distributing the RAN IGP into the inter domain ibgp and distribute the necessary labelled ibgp prefixes (MPC gateway) into RAN IGP (via BGP communities)

13 Unified MPLS Service Infrastructure

14

15 LTE MPLS VPN Service Scale Control for S1 and X2 communication LTE Export: RAN W RT, Common RT Import RAN W RT, MPC RT Core Domain Export: RAN Y RT, Common RT Import RAN Y RT, MPC RT Aggregation Domain MME Aggregation Domain LTE Transport MPLS VPNv4/v6 MTG MTG SGW/PGW SGW/PGW MTG Export: RAN X RT, Common RT Import RAN X RT, MPC RT Export: MPC RT Import: MPC RT, Common RT Export: RAN Z RT, Common RT Import RAN Z RT, MPC RT Unified MPLS transport with a common MPLS VPN for LTE S1 from all CSGs and X2 per LTE region Mobile Transport GWs import all RAN & MPC Route Targets, and export prefixes with MPC Route Target CSGs (and Pre-Aggregation ) in a RAN region import the MPC and neighboring RAN Route Targets: Enables S1 control and user plane with any MPC locations in the core Enables X2 across CSGs in the RAN region

16 Unified MPLS with Microwave Integration with Microwave Adaptive Code Modulation (ACM) Aggregation The IP/MPLS adapts intelligently to the Microwave Capacity drops Microwave Adaptive Code Modulation changes due to fading events are signaled through an Y.1731 VSM to the MPLS IP/MPLS interface Aggregation Policy Logic that updates the IGP metric on the IP/MPLS interface Microwave Fading Y.1731 VSM Signals the Microwave link speed The MPLS adapts the IGP metric of the link to the new capacity, triggering optimized SPFs that account for the capacity drops Degraded Link Cost = [n +1- n*cb/nb] * Original Link Cost Where: CB = Current BW, NB = Nominal BW, n = nodes in the ring In addition the can change the Hierarchical QOS policy on the interface with the microwave system allowing EF traffic to survive despite of the capacity drop.

17 Synchronization

18 Synchronization Needs for different applications Technology GSM WCDMA (and LTE) FDD WCDMA TDD TD-SCDMA LTE TDD CDMA2K WiMAX Mobile LTE-Advanced Services Macro BS: ±50 ppb Pico BS: ±100 ppb Frequency Read: better than WideArea BS: ±50 ppb Medium/LocalArea BS: ±100 ppb Home BS: ±250 ppb OBSAI: ±16 ppb WideArea BS: ±50 ppb LocalArea BS: ±100 ppb WideArea BS: ±50 ppb LocalArea BS: ±100 ppb WideArea BS: ±50 ppb LocalArea BS: ±100 ppb Macro Cell BS: ±50 ppb Pico Cell BS and Femto Cell: ±100 ppb Up to ± 1 ppb Average target : ± 15 ppb ±5 ppb (CoMP) Multi-Media Bcast SFN Service ± 50ppb ± 1 µs N/A N/A Phase or Time Synchronization Read: less than ± 2.5 µs between base stations ± 3 µs between base stations ± 3 µs between base stations May range from ±0.5µs to ±50µs ToD (UTC) sync should be less than 3 μs and shall be less than 10 μs Usual values between ± 0.5µs and ± 5µs CoMP, relaying function, carrier aggregation ± 0.5 µs [± 1 µs] DVB SFN Up to ± 1 ppb General agreement : ± 1 µs TDM transmission G.823/G.824/G.8261 N/A Monitoring N/A ± 1 to 100 µs ToD synchronization for 10 µs to 1 ms measurement accuracy 18

19 Synchronisation Requirements Clocking Mechanisms Comparison Clocking Mechanism Advantages Disadvantages GPS PRC/BITS SyncE/ESMC NTPv4 Reliable PRC Relatively cheap Frequency and phase Reliable PRC Generally Available Packet Based (Frequency and Phase) Physical layer (Frequency) Packet Based (Frequency and Phase) Antenna required US Govt owned No Phase Need to maintain TDM in all Ethernet deployment Requires Master w/ PRC Performance influenced by network Undefined Profiles in SP environments No Phase Every node in chain needs to support Not as robust as Open standard Some proprietary implementations

20 UMMT Synchronization Distribution Non-SyncE aware SyncE, ESMC TDM(SDH) BSC, ATM RNC TDM(SDH) SyncE 1588 PTP PRC/PR S Ethernet Fiber 1588 BC IP/MPLS Transport 1588 Phase External Synchronization Interface (Frequency) External Synchronization Interface (ToD and Phase) Global Navigation Satellite System (e.g. GPS, GLONASS, GALILEO)- PRTC, Primary Mobile Reference Packet Core Time Clock 1588 PMC Packet Master Clock Phase Mobile IP/MPLS Transport Cell Site Gateway (CSG) ASR-901, 2941 Fiber or uwave Link, Ring Aggregation Pre-Aggregation IP/MPLS Transport ME-3800X, 3600X, ASR-903 Aggregation ASR-9000 DWDM, Fiber Rings, H&S, Hierarchical Topology Core CRS-3, ASR-9000 Core Mobile Transport Gateway (MTG) ASR IP/MPLS Transport Core CRS-3, ASR-9000 DWDM, Fiber Rings, Mesh Topology

21 A 4 2 C E B 1 D F A1 Backbone A2 C1 E1 C5 C2 TE-FRR Backup tunnel NH protection C4 A1 A2 C3 C1 C5 Region Remote-LFA tunnel to PQ node C2 C4 C3 RFC-5286 defines the baseline LFA-FRR Simple, Minimum Configuration No need for additional protocols overhead like (RSVP TE) Simpler for capacity planning then TE-FRR

22 Remote LFA FRR - Protection C2 s LIB C1 s label for FEC A1 = 20 C3 s label for FEC C5 = 99 C5 s label for FEC A1 = 21 On failure, C2 sends A1-destined traffic onto an LSP destined to C5 Swap per-prefix label 20 with 21 that is expected by C5 for that prefix, and push label 99 When C5 receives the traffic, the top label 21 is the one that it expects for that prefix and hence it forwards it onto the destination using the shortest-path avoiding the link C1-C2. C1 C A1 20 Backbone C3 A2 Directed LDP session 21 Region 21 X E1 C5 C4 21

23 LoC (ms) What Is PIC or BGP FRR? Core PIC no PIC msec Prefix k PIC 250k no PIC 500k PIC 500k no PIC Prefix

24 Wholesale Consumer Broadband and Enterprise Services

25 Consumer Broadband Services Centralized BNG Distributed BNG Subscriber Aggregation Core Residential Cable/CMTS Corporate DSL/DSLAM Agg Switch Agg Switch Edge Router MPLS/IP Fiber / OLT MPLS/IP Wireless Ethernet Agg Switch Agg Switch Edge Router Cell Phones Mobility Internet Dynamic/Controlled/Accounting Stability/Performance 25

26 Enterprise VPN and Internet Service (Option-1) Subscriber Aggregation Core Residential Corporate Cable/CMTS DSL/DSLAM Agg Switch Agg Switch Enterprise Edge Router MPLS/IP Fiber / OLT MPLS/IP Wireless Ethernet Cell Phones Mobility Agg Switch Agg Switch Enterprise Edge Router Internet Pseudo-wire 802.1Q L2/L3 VLAN

27 CE PE (A-PE) e.g.: DSLAM, OLT, U-PE Service PE (S-PE) e.g: PW-HE-L3-PE PW-HE-BNG Internet Peering Aggregation LDP domain Business L3 VPNs LDP Core / Internet Core L3PE CE Pseudo-wire Headend Architecture benefits: Supports Seamless MPLS end-to-end Architecture: Flexible Edge placement Simpler resiliency between L3 PE and aggregating network Easy-to-operate service High-Availability through MPLS based network convergence Eliminates operationally cumbersome VLAN hand-off

28 Summary Metro Ethernet requirements fundamentally change with LTE/LTE-A and Converged Backhaul. One & Many Services Mobile (2G/3G/LTE), Enterprise and consumer Large Scale Can support 100K+ Devices Fast Convergence IGP FC: Simple, sub-second, always required in all areas LFA FRR and Remote LFA FRR: simple <50ms Link and BGP PIC : innovation enabling BGP to scale the IGP with simplicity

29