Cover Ethernet.1AN: Cover Ethernet.1AN 5/7/07 10:13 AM Page 3 Ethernet Reference Guide Your everyday Ethernet testing reference tool Cover Ethernet.1AN: Cover Ethernet.1AN 5/7/07 10:13 AM Page 4 This guide provides a detailed overview of Ethernet technology. It presents common Ethernet implementations in service- provider networks, the testing requirements to ensure reliable service, as well as installation and maintenance techniques. Following its introduction in the early 1970s, the Ethernet protocol for data networking has been characterized by ever-increasing popularity and adaptation. In recent years, Ethernet has become the predominant network access protocol, now used in over 95% of all local-area networks. With the advent of Gigabit Ethernet and 10 Gigabit Ethernet, this technology has matured and made its way from local-area networks to metropolitan-area networks, and now wide-area networks, challenging traditional transport protocols such as SONET/SDH and ATM. www.exfo.com Guide Ethernet.1-ang: Guide Ethernet.1AN 5/7/07 10:06 AM Page 1 Table of Contents 2.7 Ethernet Frame Tag ..............................................................................23 2.8 VLAN Tagging........................................................................................23 Symbols Used in Illustrations................................................3 2.9 Traffic Priority ........................................................................................25 2.10 Frame Bursting ......................................................................................26 1. Introduction ............................................................................................5 2.11 Jumbo Frames........................................................................................26 1.1 What is Ethernet? ..................................................................................5 2.12 Ethernet Media Access Control........................................................26 1.2 Some History............................................................................................6 2.12.1 Half-Duplex Ethernet and CSMA/CD ............................26 1.3 Ethernet in Carrier Networks................................................................7 2.12.2 Carrier Sense........................................................................27 1.4 Ethernet Naming and Standards ........................................................8 2.12.3 Multiple Access ....................................................................27 1.4.1 802.3 Naming Convention ..................................................8 2.12.4 Collision Detection ..............................................................27 1.4.2 Evolution of Ethernet Standards ........................................9 2.13 CSMA/CD Transmission Flow ..........................................................28 2.13.1 Full-Duplex Ethernet ............................................................28 2. Ethernet Nuts and Bolts ......................................................13 2.13.2 Flow Control..........................................................................28 2.1 Ethernet Logical Specifications ........................................................13 2.13.3 Pause Frame Format ..........................................................29 2.2 Basic Ethernet 2 Frame ......................................................................14 2.13.4 Auto-Negotiation ..................................................................29 2.2.1 Ethernet vs. 802.3 Frame Format ....................................15 2.13.5 Link Aggregation..................................................................30 2.2.2 Preamble and Start-of-Frame............................................15 2.14 10 Gigabit Ethernet..............................................................................31 2.2.3 Destination and Source Addresses ................................16 2.14.1 Physical-Layer Specifications............................................31 2.2.4 Type/Length ..........................................................................18 2.2.5 802.3 Logical Link Control Header ................................19 3. Ethernet Applications..................................................................36 2.2.6 Snap Header ........................................................................20 3.1 Ethernet in Local-Area Networks (LANs)........................................36 2.3 Data Field................................................................................................21 3.2 Ethernet in Access Networks ............................................................39 2.3.1 Ethernet ..................................................................................21 3.3 Ethernet in Metro Networks ..............................................................41 2.3.2 IEEE 802.3............................................................................21 3.4 Ethernet in Wide-Area or Long-Haul Networks ............................41 2.4 Frame Check Sequence ....................................................................22 3.5 Ethernet Service Types........................................................................41 2.5 Interframe Gap ......................................................................................22 3.5.1 E-Line Variants......................................................................44 2.6 Ethernet Frame Format Extensions ..................................................22 3.5.2 E-LAN Variants......................................................................45 www.exfo.com Ethernet Reference Guide EXFO 1 Guide Ethernet.1-ang: Guide Ethernet.1AN 5/7/07 10:06 AM Page 2 3.6 Ethernet Infrastructures ......................................................................45 6. Monitoring Ethernet Networks....................................71 3.6.1 Native Ethernet ....................................................................46 6.1 Ethernet Quality-of-Service Assurance............................................71 3.6.2 SONET/SDH........................................................................46 6.1.1 Performances and Traffic Monitoring ..............................71 3.6.3 Native Ethernet vs. SONET/SDH: Pros and Cons ........46 6.2 Remote Testing for Ethernet in the First Mile Deployments ..........72 3.6.4 Resilient Packet Ring (RPR) ............................................47 6.2.1 Access Line Management 3.6.5 ATM ........................................................................................48 Using the 802.3ah Standard ............................................73 3.6.6 IP/MPLS ................................................................................48 6.2.2 Demarcation Devices ..........................................................74 6.2.3 Ethernet Test-Heads ............................................................74 4. Introduction to 6.2.4 Management Software........................................................76 Installation and Provisioning............................................52 ..................................................................................................78 4.1 Quality and Performance ....................................................................52 7. Glossary 4.2 Ethernet Performance Verification ....................................................52 8. Acronyms Index ..............................................................................92 4.2.1 Test Configurations..............................................................53 4.2.2 RFC 2544 tests ..................................................................55 4.3 Fiber Characterization..........................................................................61 4.4 BERT over Ethernet ............................................................................62 4.4.1 GigE and 10 GigE BERT over Dark Fiber and PONs ......63 4.4.2 GigE and 10 GigE BERT over a DWDM Network ......63 4.5 Ethernet Service Acceptance Testing ............................................64 5. Commissioning Ethernet for Voice-over-IP and Video-over-IP Deployment ................................66 5.1 Essential Testing Techniques ............................................................66 5.2 Simulating the Customer’s Network ................................................66 5.3 Simulating Real-World Traffic Patterns............................................67 5.4 Performing Unidirectional Testing ....................................................68 2 Ethernet Reference Guide EXFO www.exfo.com Guide Ethernet.1-ang: Guide Ethernet.1AN 5/7/07 10:06 AM Page 3 Symbols Used in Illustrations Router DWDM Filter ATM or Ethernet Switch Multilayer Switch Workgroup Switch Metro DWDM Add/Drop Multiplexer SONET/SDH Add-Drop Multiplexer (ADM) DWDM Ring or Multiservice Provisioning Platform (MSPP) www.exfo.com Ethernet Reference Guide EXFO 3 Guide Ethernet.1-ang: Guide Ethernet.1AN 5/7/07 10:06 AM Page 4 Introduction Guide Ethernet.1-ang: Guide Ethernet.1AN 5/7/07 10:06 AM Page 5 Central Office Home 1. Introduction Point of Presence (POP) 1.1 What is Ethernet? Since its invention in the 1970s, Ethernet has gradually become the world’s most widely used network technology. In local-area networks (LANs), Ethernet has largely replaced all other LAN standards such as Token Ring, Business LAN ARCNET (Attached Resource Computer network), and FDDI (Fiber WAN MAN Access Distributed Data Interface). More recently,