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SC441 Computer Networks – Independent Study Boston University. Metropolitan Ethernet Networks Estella Kang Matt Powers. Metro Ethernet Networks. Typically covers several hundred miles of concentrated metropolitan areas
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SC441 Computer Networks – Independent Study Boston University Metropolitan Ethernet Networks Estella Kang Matt Powers
Metro Ethernet Networks • Typically covers several hundred miles of concentrated metropolitan areas • Explosion of Internet traffic and IP services demand for rapid scalability and dynamic functionality
Metro Ethernet Networks • Service and operational cost reduced • Scalable – up to 100Gbps • Simple – fewer protocol conversion
Services Provided by MEN • Full suite of carrier-class Ethernet services • Ethernet switching • Statistical multiplexing functionality • Bandwidth-on-demand service
Metro Ethernet Network Advantages • Service and management • Scalability • Network Reliability • Co-existence with existing infrastructure • Topological flexibility • Reduction in operational and network costs
L2/L3 Metro Ethernet • A Metro Ethernet is a computer network based on the Ethernet standard and which covers a metropolitan area. It is commonly used as a metropolitan access network to connect subscribers and businesses to a Wide Area Network, such as the Internet. Large businesses can also use Metro Ethernet to connect branch offices to their Intranet. • A typical service provider Metro Ethernet network is a collection of Layer 2 or 3 switches or routers connected through optical fiber. The topology could be a ring, hub-and-spoke (star), or full or partial mesh. The network will also have a hierarchy: core, distribution and access. The core in most cases is an existing IP/MPLS backbone, but may migrate to newer forms of Ethernet Transport in the form of 10G or 100G speeds. • Ethernet on the MAN can be used as • pure Ethernet, • Ethernet over SDH, • Ethernet over MPLS or • Ethernet over DWDM SM341073 Pengenalan Teknologi dan Jasa Telekomunikasi Semester Ganjil Tahun Ajaran 2009 - 2010
L2/L3 Metro Ethernet • The main advantages of an MPLS-based Metro Ethernet against a pure Ethernet are: • Scalability: pure Ethernet MAN are limited to a maximum of 4,096 VLANs for the whole network, when using MPLS, Ethernet VLANs have local meaning only (like Frame Relay PVC). • Resiliency: pure Ethernet network resiliency relies on STP or RSTP (30 to 1 sec convergence) while MPLS-based MANs use MPLS-based mechanism • Multiprotocolconvergence: with the maturity on pseudowires standards (ATM VLL, FR VLL, etc.) an MPLS-based Metro Ethernet can backhaul not only IP/Ethernet traffic but virtually any type of traffic coming from customer networks or other access networks (i.e. ATM aggregation for UMTS). • End to End OAM: MPLS-based MAN offers a wider set of troubleshooting • The Metro Ethernet Forum (MEF) has defined two types of services that can be delivered through Metro Ethernet: • E-Line also known as Virtual Leased Line and Point-to-Point. • E-LAN also known as Virtual Private LAN Services, Transparent LAN Services and MultiPoint-to-MultiPoint. SM341073 Pengenalan Teknologi dan Jasa Telekomunikasi Semester GanjilTahunAjaran 2009 - 2010
Example Service using E-Line Service Type • Ethernet Private Line • Dedicated UNIs for Point-to-Point connections Storage SP Dedicated TDM circuits Point-to-Point EVCs (dedicated BW) Storage SP Ethernet UNI OC-3 Ethernet UNI DS1 CE CE MEN MEN CE ISP POP CE ISP POP DS3 Ethernet UNI Internet Internet CE CE OC-3 Ethernet UNI Ethernet Private Line using E-Line Service type Private Line Analogy to E-Line Service
Example Service using E-Line Service Type • Ethernet Virtual Private Line • Supports Service Multiplexed UNI • Point-to-Point VPN for site interconnectivity Point-to-Point EVCs Point-to-Point FR PVCs Ethernet UNI Service Multiplexed Ethernet UNI FR UNI FR UNI CE FR CPE MEN MEN CE FR CPE FR CPE CE Ethernet UNI FR UNI Ethernet Virtual Private Line using E-Line Service type Frame Relay Analogy to E-Line Service
SONET/SDH Implementation • Metro core and metro access ring topology • ADM • DACS • TDM
SONET/SDH Constraints • Complex, multi-tiered, hierarchical network • Limited Scalability • Expensive
Multi-Protocol Label Switching (MPLS) • Label switching to forward data by mapping VLAN tags to label switched paths (LSPs) • Load sharing by switching path around bottlenecks to less congested links • Dedicated backup LSP and fast reroute when a connection failure occurs
LogikaBerfikirnya Backbone Operator • Pada kecepatan tinggi IP terlalu komplek. • Pada kecepatan tinggi IP terlalu memakan resource CPU. • Operator perlu teknologi yang effisien.
LogikaBerfikirPelanggan • Tujuan direct hanya terbatas. • Misalnya Lampung --> Jakarta, Medan, Surabata dan Internet. • Sangat terbatas, tidak banyak tujuan kecuali Internet. • Aplikasi pelanggan juga terbatas. • E-mail, web, sekali-sekali video conference. • Perlu customisasi per pelanggan yang mudah.
Inti-nya .. • Label Switch – jauh lebih sederhana & effisien. • TCP/IP – kompleks & tidak effisien. • Label Switch – jauh lebih baik untuk backbone daripada IP.
TopologiJaringan MPLS • LIB = Label Information Base • LSR = Label Switched Router
BeberapaIstilah • LSR, Label Switched Router – router yang mampu melakukan switching dengan label. • LIB, Label Information Base – kira-kira tabel routing label tempat melihat outbound Interface & label yang digunakan utk mengirim paket.