LTS Gigabit Ethernet Is it a disruptive technology

LTS Gigabit Ethernet: Is it a disruptive technology? Ronald Skoog Telcordia Technologies 732 -758 -2406 rskoog@research. telcordia. com An SAIC Company. Slide 1

Outline Background: – The Metro Network Environment and the Technology Choices Ethernet and Gb/10 Gb Ethernet Technology Background Gb/10 Gb Ethernet Capabilities and Deficiencies Related Standards and Industry Forum Activities and Service Providers Conclusions and Summary LTS ©Telcordia Technologies, Inc. Slide 2

Metro Network Environment Residential LAN MAN SSP BOTTLENECK!! • SONET-based TDM networks • Inefficient for data traffic • stranded capacity, • no statistical gain • Long provisioning times ISP POP Internet ISP backbone POP ASP Business Services/Apps – Access to Internet, ASPs, SSPs, etc. – LAN-LAN, VLANs, VPNs – Flexible, granular bandwidth choices – Quick and efficient service provisioning – Voice and video Residential Services/Apps x. DSL, Cable, ETTH HDTV Video Games Voice LTS ©Telcordia Technologies, Inc. Slide 3

New Alternatives to SONET Residential MAN LAN ne e ttl o B LAN ck ! -n. DS 0, T 1, T 3 Leased line - TDM-based SONET New Solutions ISP Internet ISP POP backbone POP MAN LAN Next Generation MAN ATM VP Ring MSPP NG SONET (VC, GFP) RPR DPT i. PT WDM ©Telcordia Technologies, Inc. Gigabit Ethernet LTS Slide 4

Ethernet Protocol Structure Logical Link Control (LLC) Layer 7 Application Layer 6 Presentation Layer 5 Session Layer 4 Transport Layer 3 Network Layer 2 Data Link Layer 1 Physical MAC Bridging 802. 2 802. 1 D 802. 1 Q 802. 1 p Media Access Control (MAC) Physical Signaling Ethernet-Specific 802. 3 Media OSI Model Major IEEE Sublayers 1518 Bytes Length 64 Bytes 64 bits 48 bits Preamble Destination MAC Address Source MAC Address 16 bits Length/ Type 46 to 1500 Bytes Data/LLC 32 bits Frame Check Sequence Ethernet Frame Structure ©Telcordia Technologies, Inc. LTS Slide 5

Evolution from Shared-Media, Half-Duplex to Dedicated-Media, Full-Duplex Collision (CSMA/CD resolution) 10 BASE 2 or 10 BASE 5 (Coax Cable, Bus Topology, 1985) Repeater Dedicated Media Collision (CSMA/CD resolution) UTP UTP Half-Duplex 10 BASE-T (Star Topology, UTP cable, 1990) Bridge/Switch UTP Collision-Free Full Duplex 10/100 BASE-T (1992/1993) ©Telcordia Technologies, Inc. The Critical Development • LAN backbone and NIC speeds are independent • Networking is now possible LTS Slide 6

Switched Gb. E Network Architecture Gb. E Architecture Multi-Tenant Unit Building (MTU) LAN 1 LAN 2 ISPs Access Gb. E Switch • • • LAN n Gb. E IP Backbone Providers Core Gb. E Switched Network Gb. E L 2/3 Switch Multi-tenant Building Gb. E ASPs Gb. E L 2 Switch Multi-tenant Building Access Gb. E Switch Multi-tenant Building Server Farm Optical Ethernet Service Categories • Internet access • LAN-LAN Interconnection (Ethernet PL) • Metro Transport (Transparent LAN Service) ©Telcordia Technologies, Inc. Slide 7 LTS

Gb. E and SONET Network Architectures Gb. E Architecture Multi-Tenant Unit Building (MTU) LAN 1 ISPs Access Gb. E Switch LAN 2 Multi-tenant Building Access Gb. E Switch • • • Core Gb. E Switched Network Gb. E LAN n IP Backbone Providers Multi-tenant Building Gb. E Multi-tenant Building ASPs Gb. E L 2 Switch Office RFT RFT DS 0 -DS 3 Gb. E L 2/3 Switch SONET Architecture OC 12 OC 48 TM OC 3 OC 12 Server Farm ADM OC 12 OC 48 DCS ADM (hub) OC 3 -OC 12 IXC DCS OC 48 Collector Ring ©Telcordia Technologies, Inc. ADM Core Ring ATM ISP LTS Slide 8

10 Gigabit Ethernet Layer Architecture 802. 3 Media Access Control Reconciliation 64 B/66 B coding for Serial PMDs 8 B/10 B coding for WWDM PMD XGMII SONET framer PCS PHY WIS PMA PMD 850 nm Serial (MMF) 1310 nm Serial (SMF) 1550 nm Serial (SMF) 1310 WWDM Parallel (MMF, SMF) PMA PMD MDI WAN PHY LAN PHY Medium (Optical Fiber) • At Layer 2, 10 Gb. E is mostly unchanged, except NO SHARED MEDIA • Two Physical (PHY) Layers: LAN PHY and WAN PHY • Multiple Physical Media Dependent (PMD) layers: – MMF and SMF – Minimum distance requirements from 65 m to 40 km ©Telcordia Technologies, Inc. LTS Slide 9

10 Gb. E Applications Long Haul Network ELTE* DWDM Long Haul Links WAN PHY 10 Gb. E Metro Network 10 Gb. E 10 Gb. E WIS Path Core Routers 10 Gb. E Edge Routers 10 Gb. E Regional/Metro Edge/Core Routers 10 Gb. E Access Routers * ELTE Core Routers 10 Gb. E • • • • 10 Gb. E = Ethernet Line Terminating Equipment Access Routers Server Farm Connectivity LTS ©Telcordia Technologies, Inc. Slide 10

Gb/10 Gb Ethernet Capabilities Full duplex point-to-point links with long reach to 40 -70 km Big port cost advantage over SONET and ATM (~8: 1 in port costs) ‘Plug-and-play’ VLAN capability (802. 1 Q) Spanning tree routing (802. 1 D) at layer 2 Aggregate link capability (802. 3 ad) Priority capability (aggregate flow Qo. S) provided by 802. 1 p at Layer 2 and Diff. Serv at layer 3 Policy based Qo. S Traffic policing, shaping and monitoring at customer interface Optical Ethernet has a significant arsenal of Networking Capabilities LTS ©Telcordia Technologies, Inc. Slide 11

Gb/10 Gb Ethernet Deficiencies Protection/restoration times are on the order of 1 second compared to SONET 50 ms capability Qo. S is in a similar state as IP Qo. S – over-provisioning needed to provide delay/jitter sensitive apps. – Qo. S provided for traffic aggregates, not individual flows – Routing protocols don’t balance load very well on link capacity Performance monitoring and fault management are not as good as SONET and ATM. – Ethernet provides no overhead for performance monitoring, alarms, protection signaling, etc. 10 Gb. E WAN PHY has some of this capability Not clear how well Gb. E OA&M will scale (e. g. , service provisioning, loopbacks, single-ended maintenance) LTS ©Telcordia Technologies, Inc. Slide 12

Missing OAMP Functionality in Ethernet Fault Detection, Sectionalization, and Alarming Protection and Restoration (SONET: 50 msec) Secure Single-Ended Maintenance PHY-Layer Link Quality Monitoring (BER) Loopbacks LTS ©Telcordia Technologies, Inc. Slide 13

Why is Ethernet Cheaper? Simple Technology Backwards Compatibility Strict Standardization and Interoperability Customer Familiarity and Acceptance Large Volumes OPTICS: High-Volume, Mass Assembly Plastic Packaging ELECTRONICS: Byte-oriented Line coding (e. g, 8 B 10 B) Simple frame delineation Relaxed timing and Jitter ©Telcordia Technologies, Inc. Source: Martin Nuss, Internet Photonix LTS Slide 14

Spanning Tree Capability (802. 1 D) Routing in layer 2 switched networks uses the spanning tree algorithm – spanning tree routing is prone to traffic concentrating on a small number of links and switches; – spanning tree reconfiguration is relatively slow (30 -50 seconds required); • An improved algorithm is being developed (P 802. 1 w) that will converge in < 1 sec. (maybe in 10 s of ms) • Multiple spanning tree capability is being developed in P 802. 1 s LAN L 2 Switch L 2 Switch LAN Spanning Tree Links L 2 Switch LAN SWITCHES LEARN TOPOLOGY BY EXCHANGE OF CONFIGURATION MESSAGES ©Telcordia Technologies, Inc. LTS Slide 15

Virtual LAN (VLAN) Capability Virtual LAN and priority capabilities are provided by 802. 1 Q/p: – a VLAN tag is provided by 802. 1 Q to identify VLAN membership Limited to 4096 VLANs – this is a potential scalability issue – the VLAN tag has a 3 -bit priority field that allows 8 possible service classes (matches Diff. Serv’s 8 possible classes) Why VLANS? – LAN scalability: limits broadcast domains (limits broadcast storms); also limits multicast, chatty protocols, etc. , reducing overall network traffic. – Network efficiencies: traffic flows from different VLANS can be segregated – Allows non-physical grouping of nodes that share similar resources – Allows easy changing of LAN membership – Reduces the amount of level 3 (IP) routing – Security: limits snooping; authentication required (via GVRP) to join VLAN LTS ©Telcordia Technologies, Inc. Slide 16

VLANs and MPLS-Based Transparent LAN LER Services A Architecture based on Martini IETF Draft LSR CPE LER A LSR A CPE LER B B CPE VC LSP VLAN VC LSP Ethernet Tunnel LSP DA SA Etype Tunnel VC 0 x 8847 Label Ethernet 64 bits Outer Ethernet Header Label Stack Original Ethernet Frame 48 bits 16 bits 46 to 1500 Bytes Dest Source Length/ Preamble MAC TPID TCI Type Address User Priority (3) ©Telcordia Technologies, Inc. CFI (1) Data/LLC VLAN ID (12) 32 bits Frame Check Sequence LTS Slide 17

Related Standards and Industry Forum Activities Resilient Packet Ring (RPR) – IEEE 802. 17 – Data efficient ring (distributed switch) using spatial reuse, 50 ms protection, and bandwidth management (allocation and fairness) Ethernet in the First Mile (EFM) Study Group – IEEE 802. 3 ah – Remote management of customer terminal for testing (loopbacks) – Link OAM overhead for BER monitoring, alarm indication, etc. ITU Study Group 13 (Multi-Protocol and IP-based Networks &. . . ) – Link OAM and end-to-end OAM – Leverage link OAM from EFM Metro Ethernet Forum (Industry Alliance) – Ethernet service definitions, technical specifications, and interoperability – MPLS protection mechanisms to 50 ms protection – OAM&P is on the agenda (leverage EFM link OAM work) LTS ©Telcordia Technologies, Inc. Slide 18

Service Providers with Ethernet Services/Plans Source: RHK Inc. LTS ©Telcordia Technologies, Inc. Slide 19

Is Gigabit Ethernet a Disruptive Technology? We believe that Gb. E is likely to be a Disruptive Technology It has a huge cost advantage – ~8 -to-1 in port costs, less in provisioning and operations Currently serving niche markets – Internet access at 20%– 30% equivalent SONET $/bps prices – IP-based (i. SCSI) SAN or data backup solution for smaller sites giving them Fibre Channel like performance No ‘killer’ issues have been identified There will always be gaps in capabilities, – but they are getting smaller, and – closing the gap may not be worth the price LTS ©Telcordia Technologies, Inc. Slide 20

Conclusions There is a Race going on at the Optical Edge The main contenders are Gb/10 Gb Ethernet, MSPP technologies and RPR technology. – The MSPPs and RPRs may become more Ethernet-based – The SONET-based MSPPs and RPRs may have more competitive cost structures It is not clear which technology direction will prevail – Is multi-service/Multi-protocol capability needed, or will Ethernet become the ubiquitous layer 2 standard? There is no one answer for all networks – Options need to be carefully considered for each carrier and service provider But, Gb. E Technology will be a Major Player LTS ©Telcordia Technologies, Inc. Slide 21