© Copyright 2007 Turin Networks, Inc. All rights reserved. 1 Carrier Ethernet-Based Converged Services Infrastructure using Ethernet over PDH Enables new capabilities over ubiquitous T1/E1 Access Networks October 15, 2007 Ralph Santitoro Director of Carrier Ethernet Solutions

© Copyright 2007 Turin Networks, Inc. All rights reserved. 2 Market Opportunity for Ethernet over Copper PDH Access Networks Over 86% of businesses do not have access to Fiber These businesses typically have 1 to 2 DS1s used for: Internet Access, VoIP and IP VPN Bandwidth is growing but sub-10Mbps appears to be the “sweet spot” These business locations often part of a multi-site enterprise Source: Vertical Systems Group

© Copyright 2007 Turin Networks, Inc. All rights reserved. 3 What is Ethernet over PDH (EoPDH)? PDH (Plesiochronous Digital Hierarchy) Term to collectively refer to DS1/DS3 and E1/E3 circuits The ‘copper’ electrical circuits in the digital hierarchy Leverages benefits of Ethernet to deliver converged services over PDH access network (DIY or Managed Service) Site-to-site and multi-site ‘hub and spoke’ Layer 2 VPNs Frame Relay migration and replacement Ethernet Access to IP services Internet Access, IP VPNs, IP Telephony (VoIP) Service Bandwidth Options (technology dependent) Up to 12Mbps (8 bonded DS1s) or 24Mbps (16 bonded DS1s) Up to 16Mbps (8 bonded E1s) or 32Mbps (16 bonded E1s) Up to 32Mbps (1 E3) Up to 45Mbps (1 DS3) Ethernet over PDH (EoPDH) also referred to as Ethernet over TDM (EoTDM) or Ethernet over Serial

© Copyright 2007 Turin Networks, Inc. All rights reserved. 4 Two technologies used to deliver EoPDH PPP/MLPPP/BCP-based EoPDH (RFC1990 / RFC3518) for encapsulation, bonding and bridging GFP/VCAT/LCAS-based EoPDH (ITU-T G.8040) GFP (G.7040) for encapsulation, VCAT (G.7041) and LCAS (G.7042) for bonding Device support EoPDH Aggregation Devices MLPPP/BCP-based EoPDH aggregation supported by: PDH interface and protocol processor add-in cards for routers New EoPDH edge aggregation devices GFP-based EoPDH aggregation supported by: EoPDH add-in cards for Multiservice Provisioning Platforms (MSPPs) CPE Devices MLPPP/BCP-based EoPDH supported on most CPE WAN routers and IADs GFP-based EoPDH supported on new types of CPE devices

© Copyright 2007 Turin Networks, Inc. All rights reserved. 5 How is EoPDH Deployed ? Ethernet Frames enter EoPDH CLE device and encapsulated Into PPP/MLPPP for transport over PDH network LEC multiplexes DS1s into channelized DS3 circuits or Microwave Backhaul provider transports DS1 circuit data DS1s or channelized DS3 circuits terminated on EoPDH Aggregator DS1s extracted from chDS3s, MLPPP terminated and Ethernet Frames reconstructed EoPDH preserves original Ethernet 802.1Q tagged frame, adds IEEE 802.1ad S-VLAN tag (QinQ) and passes to Ethernet Transport or IP/MPLS Network LEC EoPDH CLE EoPDH Aggregator Untagged or C-VLAN-tagged Ethernet Frame ETH IP IEEE 802.1ad S-VLAN Tagged Ethernet Frame ETH IP Microwave Backhaul Provider Enterprise or Cell Site RAN Ethernet Transport Network Channelized DS3s IP ETH PPP T1, Bonded T1s or T3 IP ETH PPP

© Copyright 2007 Turin Networks, Inc. All rights reserved. 6 Why Ethernet over PDH ? Enables new Ethernet-based services Over existing Copper PDH Access Network Facilities with no speed or distance limitations T1s are the most widely deployed access network technology for businesses data networking in North America Fits within Provider’s existing network/business operations In many cases, can use existing CLE devices Fits within existing T1 Internet access service infrastructure & NOC Simplifies Access/Aggregation Networks Terminates TDM PDH circuits as close to subscriber as possible Subscriber IP traffic is “backhauled” over Ethernet transport network Layer 2 VPN switching performed locally as needed Deploy fewer, larger routers at the IP service edge Lower cost (CapEx) Ethernet switching and transport used at Central Offices or Co-location Facilities Resulting in a Simplified Network Architecture

© Copyright 2007 Turin Networks, Inc. All rights reserved. 7 Which EoPDH approach and why? MLPPP/BCP-based EoPDH Solution Used for Retail Service Delivery of Ethernet and IP services Service providers have widely deployed base of CLE WAN routers and IADs that use MLPPP that can support BCP They just enable BCP via configuration change on the device Used for Wholesale Service Delivery Backhaul of CDMA IP RAN equipment over DS1s/E1s WCDMA / UMTS R5 & R6 and CDMA 1xEVDO use MLPPP GFP/VCAT/LCAS-based EoPDH Solution Used for Wholesale Service Delivery Backhaul of IP-based RAN equipment with Ethernet output Bonds up to 16 DS1s/E1s addressing higher BW requirements Enables a common protocol suite to be used across an Ethernet over SONET/SDH transport network Both approaches provide different benefits and depend upon the application to be supported

© Copyright 2007 Turin Networks, Inc. All rights reserved. 8 Ethernet over PDH Solution Summary - North American Example EoPDH for Aggregation of Retail Ethernet and IP Service Delivery DS1s LEC Router, IAD or EoPDH CPE IP Service Networks EoPDH Aggregation chDS3s Enterprise DS1s or DS3 Central Office or Co-location facility Internet, VoIP, IP VPN Ethernet Transport Network DS1 EoPDH for Aggregation and Backhaul of Mobile IP RANs DS1s LEC EoPDH CPE EoPDH Aggregation chDS3s DS1s or DS3 Wireless Hub Site Mobile Switching Center Ethernet Transport Network CDMA IP RANs with PDH output Microwave Backhaul of PDH Circuits DS1s IP RAN with Ethernet output