Adtran, Inc. 2007 All rights reserved

Agenda Intro Basic IP/Ethernet Technology Review Advanced IP/Ethernet Technology QoS Services Migration Applications ATM to Ethernet Interworking Business Services Migration PPP, MLPPP, FR 2

Why Are We Here? Discuss the migration from Legacy (ATM, TDM) to Ethernet-based Aggregation Review basic IP/Ethernet technology Discuss more advanced IP/Ethernet technologies used in IP DSLAMS Discuss key features such as QoS and CoS that enable advanced services migration 3

Next Generation Networks Ethernet-based Access Network Fiber to the Node (FTTN) Fiber to the Premises (FTTP) Triple Play Services 20-80 Mbps per subscriber 4

Services Migration Goals Maximize product lifecycle of existing ATM DSLAMs Leverage already installed base Maximize return on investment Provide ubiquitous migration strategy to Next- Generation IP/Ethernet core Same for all vendors Low impact to existing network Edge aggregation and interworking Minimize impact on existing inter-office transport Allow higher speed service offerings 5

Private Line Market Stats Enterprise customers rely on Private Line services to support data, voice and video applications that require dedicated connectivity and predictable performance. Typical applications for Private Lines are private router intranets, private backbone networks, data center backup, PBX interconnection, video and high resolution imaging. For this analysis, a retail Private Line is defined as a dedicated "point-to-point" circuit purchased by an enterprise customer to support a secure wide area networking environment. Vertical's analysis shows that IP applications utilize 61% of U.S. customer Private Line bandwidth. Video is the second largest application based on bandwidth, followed by legacy Voice. Price, reliability and security are the primary customer purchase drivers for Private Lines. Service alternatives for point-to-point applications are Business DSL, Business Ethernet, and Business Cable Modem. For some applications, cost savings may be realized by the replacement of distance sensitive Private Lines with distance insensitive services like IP/MPLS VPNs. The Metro and Long Haul segments accounted for 24% and 76%, respectively, of the $10.4 billion U.S. private line market in 2008. Private lines are a substantial revenue source for providers. In the U.S., Private Line revenue is equivalent to the combined markets for Frame Relay plus Business Ethernet. Source: Vertical Systems Group, www.verticalsystems.com 6

Frame Relay Market Stats Customer migration from Frame Relay to IP/MPLS VPN services is ongoing. Conversions to IP VPNs are typically initiated by a "trigger", like VoIP or another new IP-based application. Hybrid network configurations using FR/IP connections are an interim step for some customers. Business Ethernet services are gaining traction as a network migration path for Frame Relay customers, particularly those with metro networks and high bandwidth requirements. Ethernet VPLS (Virtual Private LAN Service) offerings are positioned to address the requirements of Frame Relay customers seeking network scalability and improved connectivity. $8B FR services platforms consist of multi-layer network architectures, typically using a backbone IP/MPLS or ATM network, which enables QoS (Quality of Service) and SLA (Service Level Agreement) guarantees. For each port or Frame Relay UNI (User-Network Interface), the Service Provider provisions how the network handles user traffic via softwarebased Permanent Virtual Circuits (PVCs) and Classes of Service (CoS). IP is the dominant protocol on Frame Relay networks, accounting for 95% of U.S. bandwidth utilization. However, many Frame Relay customers rely on Frame Relay services to support legacy non-ip data protocols (e.g., SNA, etc.). Voice and video are niche applications for Frame Relay. Source: Vertical Systems Group, www.verticalsystems.com 7

TR-059 Architecture DSL Forum s TR-059 Architectural Model depicting an ATM connection from the Access Node (DSLAM) 8

TR-101 Architecture DSL Forum s TR-101 Architectural Model depicting an Ethernet connection from the Access Node (DSLAM) 9

Why IP over ATM? Higher bandwidth support Services requiring QoS, multicast, and high availability are prohibitive to deploy in pure ATM environments As a result of pushing the Access Nodes closer to the subscribers in order to increase bandwidth, the number of Access Nodes has significantly increased in SP networks. Technologies such as Gigabit Ethernet and GPON allow for easier delivery of large amounts of bandwidths to a highly distributed Access Node topology. 10

DSL Rate/Reach and IPTV Bandwidth Requirements 11

OSI Model Open System Interconnection ISO (International Organization for Standardization) standard Standard reference point for networking Composed of 7 layers Each layer talks to its adjacent layers Each layer talks to its corresponding layer on the receiving end 13

7 Layers of the OSI 14

Encapsulation 15

Application Layer 16

Transport Layer 17

Network Layer 18

Data Link Layer 19

Physical Layer 20

IEEE 802 Specification 21

The MAC Address 22

Ethernet Frame 23

VLAN Basics Same Broadcast Domain Security Logical Subnet Efficient Bandwidth Utilization Port-Based or Dynamic Problem Isolation 24

Without VLANs 25

With VLANs 26

Types of VLAN Ports Access Port Only a member of 1 VLAN Trunk Port Contains multiple VLANs 27

802.1q VLAN Tagging 28

IEEE 802.1q VLAN Tag Definitions TPID 2 bytes TCI 2 bytes User Priority 3 bits CFI 1 bit VLAN ID 12 bits TPID: Tag protocol Identifier always 0x8100 for IEEE 802.1q TCI: Tag control information User Priority: 3 bit field used for marking IEEE 802.1p priority CFI: Canonical format indicator VID: VLAN identifier that identifies traffic as a member of a specific VLAN 29

PPP Intro The Point-to-Point Protocol (PPP) originally emerged as an encapsulation protocol for transporting IP traffic over point-to-point links. PPP also established a standard for assigning and managing IP addresses, asynchronous and bitoriented synchronous encapsulation, network protocol multiplexing, link configuration, link quality testing, error detection, and option negotiation for added networking capabilities. PPP provides a method for transmitting datagrams over serial point-to-point links, which include the following three components: A method for encapsulating datagrams over serial links An extensible LCP to establish, configure, and test the connection A family of NCPs for establishing and configuring different network layer protocols PPP is capable of operating across any DTE/DCE interface. PPP does not impose any restriction regarding transmission rate other than those imposed by the particular DTE/DCE interface in use. Six fields make up the PPP frame. The PPP LCP provides a method of establishing, configuring, maintaining, and terminating the point-to-point connection. 30

U-Interface Protocol Stacks The U-Interface is located between the RG and the Access Node 31

802.1q-in-q / 802.1ad The 802.1ad standard allows a service provider to add an additional VLAN tag to the existing 802.1q tag. This method is also called stacked tags and 802.1q-in-q. Advantages: - Greater scalability - Security via isolation of customer traffic - Preservation of existing customer VLAN structures - Simplicity due to service provider not having to manage the CPE devices 32

802.1ad Terms C-VID VID value of some C-Tag C-VLAN The VLAN defined by some C-VID C-Tag The innermost VLAN tag S-VID VID Value of some S-Tag S-VLAN The VLAN defined by some S-VID S-Tag The outermost or single VLAN tag Priority Tags A priority-tagged frame is a tagged frame whose header carries priority information but carries no VLAN identification information 33

802.1q-in-q / 802.1ad Untagged, 802.1q-Tagged, and Double-Tagged Ethernet Frames 34

802.1q-in-q / 802.1ad Broadband Ethernet-based DSLAM Model of Q-in-Q VLANs 35

Service Mapping for Triple Play Networks 36

What is QoS? 38

QoS Terms Delay The time it takes for a packet to be sent from one network device to another. Total delay from start to finish is called latency. Jitter The variation in delay. Loss Packets being dropped without delivery. QoS is used to alleviate these conditions Note: Voice over IP has stringent jitter and latency requirements and relaxed loss requirement. Video over IP has a very stringent loss requirement and relatively relaxed jitter requirement. 39

Types of QoS Best Effort A network that simply forwards packets in the order they were received. No real QoS. Integrated Services (IntServ) Model Prearranges a path for priority data from source to destination before traffic is sent. Typically via the protocol RSVP. This method is not very scalable and difficult to maintain. Differentiated Services (DiffServ) Model Permits each network device to handle packets on an individual basis. QoS is implemented on a per-hop behavior so each router or switch performs their own QoS methods. 40

Layer 2 QoS Classification IEEE 802.1p enables layer 2 prioritization 3 priority bits used for CoS on 802.1p compliant devices 8 levels of priority (0-7) CoS of Seven is the highest priority 41

802.1p Priority Bits 42

Layer 3 QoS ToS Byte 43

Ethernet Port CoS Output Queues 44

Queuing Methods: Strict Priority 45

Adtran, Inc. 2008 All rights reserved 47 Goals Maximize product lifecycle of existing ATM DSLAMs Leverage already installed base Maximize return on investment Provide ubiquitous migration strategy to Next- Generation IP/Ethernet core Same for all vendors Low impact to existing network Edge aggregation and interworking Minimize impact on existing inter-office transport Allow higher speed service offerings

Adtran, Inc. 2008 All rights reserved ATM/Ethernet Migration No Impact to Existing Services 48 Provision Total Access 5000 N x GE to IP/Ethernet Core Carrier ISP subscribers N x DS3 or OC3 to ATM Core 3 rd Party ISP subscribers Does not impact current high speed internet service Provision VPI/VCI subscriber information Drawn from the existing provisioning database on a per DSLAM basis VPI/VCI assignments identify Carrier ISP & 3 rd Party ISP subscribers per DSLAM ATM DSLAMs BPON OLTs DS3 or OC3 Cross Connect ATM DS3 ATM or ATM Network OC3 ATM 3 rd Party ISP Subscribers 3 rd Party ISP Handoff ATM ATM Carrier ISP Router/Subscriber Termination IP Internet N x GE Carrier ISP Subscribers IP

Adtran, Inc. 2008 All rights reserved 49 Low Risk Efficient Strategy Transfer DS3 or OC3 cross connects from ATM network to Total Access 5000 Eliminates removing existing ATM DSLAMs out of service for long periods of time Eliminates costly common switch fabric replacements Minimizes migration risk by not changing ANYTHING on the existing ATM DSLAMs Transfer can be done during the maintenance window Low risk migration on a per system basis Allows large numbers of subscribers to be quickly and efficiently migrated ATM DSLAMs BPON OLTs DS3 or OC3 Cross Connect ATM DS3 ATM or ATM Network OC3 ATM 3 rd Party ISP Subscribers 3 rd Party ISP Handoff ATM ATM Carrier ISP Router/Subscriber Termination IP Internet N x GE Carrier ISP Subscribers IP

Adtran, Inc. 2008 All rights reserved ATM to Ethernet Interworking with 3 rd Party ISP Handoffs 50 Carrier ISP subscribers are provisioned for ATM to Ethernet Interworking per RFC 1483/2684 PPPoE or IPoE AAL5 traffic S tag per DSLAM, C tag per subscriber Uplink via integrated GE links on the Total Access 5000 Switch Module 3 rd Party ISP subscribers are not interworked PPPoA, PPPoE, IPoA or IPoE ATM over Ethernet tunnel across the backplane to an ATM Line Module Switched to the existing ATM network Preserves existing ATM OAM capabilities for 3 rd Party ISPs DS3 ATM or OC3 ATM VPI/VCI = Carrier ISP Subscriber VPI/VCI = Carrier ISP Subscriber VPI/VCI = Carrier ISP Subscriber VPI/VCI = Carrier ISP Subscriber VPI/VCI = Carrier 3 rd Party ISP Subscriber VPI/VCI = Carrier 3 rd Party ISP Subscriber ATM to Ethernet Interworking per RFC 1483/2684 ATM over Ethernet across Backplane VLAN = Carrier ISP Subscriber VLAN = Carrier ISP Subscriber VLAN = Carrier ISP Subscriber VLAN = Carrier ISP Subscriber VPI/VCI = Carrier 3 rd Party ISP Subscriber VPI/VCI = Carrier 3 rd Party ISP Subscriber N x GE via Switch Module Carrier ISP Subscribers DS3 ATM or OC3 ATM 3 rd Party ISP Subscribers

Adtran, Inc. 2008 All rights reserved Next Generation Core with IP DSLAM Access Growth 51 Maximize the investment in existing ATM DSLAMs Reduce core network costs by minimizing the need for legacy ATM Subscriber Authentication (BRAS) Provide a cost-effective strategy for DSL subscriber growth Scalable next-generation access and aggregation platform Up to 10 Gbps per slot with N x GE uplinks for increased subscriber bandwidth Multi-service capabilities over both copper and fiber ATM DSLAMs BPON OLTs DS3 or OC3 Cross Connect DS3 ATM or ATM Network OC3 ATM 3 rd Party ISP Subscribers 3 rd Party ISP Handoff ATM ATM Carrier ISP Router/Subscriber Termination IP Internet VDSL2 Growth N x GE Carrier ISP Subscribers IP

Business Service Migration Application - Total Access 5000 serving as a TDM aggregation hub to migrate these services to the IP infrastructure. Traditional business services Primarily targeted at existing full rate TDM services Migration of Point-to-Point (PPP) or Frame Relay circuits Edge interworking into more efficient Ethernet Total Access 5000 reduces embedded costs for legacy services Leverage TA5000 investment in customer networks Minimize DCS, SONET transport IOF and Router port CAPEX Restore capacity on SONET IOF network Maximize use of the emerging IP network 53

Business Service Migration Central Office Central Office Core Central Office DS1 SONET SONET DS1 over Channelized Optical Interface Customer router with DS1 interface DCS DCS DCS Channelized DS3 or OC3 GE Customer router with DS1 interface DS1 TA5000 GE IP Network WAN Service Router Direct termination of DS1 circuits from customers or Channelized DS3/OC3 from multiplexers or the DCS. Extraction of L3 packets from the DS1 with transport over Ethernet. Ethernet transport relieves SONET network congestion, reduces DCS cost and eliminates more costly legacy router port interfaces. 54

Basic Business Service Migration Business Service Migration Key Features Single shelf application Single customer per T1 EVPL type = PPP Unique S-Tag per customer Similar to EoCu DSCP to P-Bit mapping Supported mixed application with EoCu E.SHDSL and Bonding Protect Management EMS CLI, no Menus Voice, Data Up to 10Gbps PPP/MLPPP T1 CPE Router or IAD 55

A little more detail Link Control Protocol (LCP) establishes PPP link session. Link Quality Management (LQM) allows Customer Router to request PPP link quality reports from Access Module. Network Control Protocol (NCP) manages operation of PPP group. Internet Protocol Control Protocol (IPCP) defines how IP is encapsulated in PPP. 56

BSM Continued Business Service Migration Key Details No Oversubscription of GigE No 1:1 Redundancy Supports both R and NR LMIO Modules Single Shelf application Local Mgmt = CLI EMS B05SP2 More protocols (Future Releases) MLPPP Frame Relay IMA Voice, Data Up to 10Gbps PPP/MLPPP T1 CPE Router or IAD 57

Adtran, Inc. 2008 All rights reserved 58 Summary Right product at the right time Maturation of IP/Ethernet standards Convergence of services over packet Total Access 5000 solution brings a single platform capable of addressing multiple applications Ubiquitous ATM/Ethernet Interworking CO or RT based IP DSLAM with DSL Ethernet edge-aggregation of IP DSLAMs FTTP with GPON Innovative solutions to address carrier s network & services evolution