1 1 1 Wide Area Networks (WAN) - Synchronous Digital Hierarchy (SDH) AAU Jens H. Sørensen 20 Oktober 2005

2 2 Table of Contents Objectives Introduction to WANs Typical WAN Technologies SDH Protocol SDH Equipment SDH Networks SDH Network Management SDH Services (partly 2nd part) WDM/OTN (2nd part) Network availability, restoration and automatic protection (2nd part) Next/new Generation SDH and relations to IP, ATM, WDM, Ethernet … (2nd part) Network Synchronisation (2nd part)

3 3 Objectives Discussion of LAN versus WAN, scaleability issues WAN technologies, overview Typical WANs, examples, SDH Relations to networks based on Ethernet/IP/ATM/DSL … Upcoming WAN networks

4 4 What is a WAN? Definition of "WAN" according to Webopedia: A computer network that spans a relatively large geographical area.computernetwork Typically, a WAN consists of two or more local- area networks (LANs).WANlocal- area networks (LANs) Computers connected to a wide-area network are often connected through public networks, such as the telephone system. They can also be connected through leased lines or satellites. Computersnetworknetworksleased lines The largest WAN in existence is the Internet.Internet

5 5 Introduction to WANs

6 6 Introduction to WANs Example High Capacity Links

7 7 Introduction to WANs Example Physical and logical Links

8 8 Introduction to WANs - scaleability Can Ethernet based LANs be connected nationwide supporting millions of users? Scaleability issues (Ethernet) –no. of MAC addresses, VLANs, broadcast domains (ARP), STP convergence, performance of MAC and CSMA/CD under high load, QoS etc.. –Creation of hierarchical networks –Long distance optical systems Scaleability issues (IP) –routing tables/IP-address aggregation, rearrangement of fixed IP-addresses, QoS Other technologies are currently used…

9 9 Introduction to WANs Ethernet: MAC, LLC TCP, UDP IP SDH, PDH, DXC 1/0 radio links, satellite, fiber, copper, WLAN …. ATM MPLS 10/100/1000 BASET, TX, SX, LX, FX…

10 Typical WAN Technologies

11 WAN Technologies WAN capacity levels: –0: 64 kbit/s –1: 2 Mbit/s (PDH) –2: 8 Mbit/s (PDH) –3: 34 Mbit/s/ 45Mbit/s (PDH) –4: 140/155 Mbit/s (PDH/SDH STM-1, SONET OC-3) –5: 622 Mbit/s (SDH STM-4, SONET OC-12) –6: 2,5 Gbit/s (SDH STM-16, SONET OC-48) –…….

12 WAN Technologies DXC 1/0 Plesiochronous Digital Hierarchy (PDH) Synchronous Digital Hierarchy (SDH, SONET) ATM, Frame Relay PSTN, ISDN Radio Links Satellite + IP Ethernet …..

13 WAN Technologies Why not only concentrate on IP/ethernet networks? –Scaleability issues –SDH, PDH … are essential parts of all incumbent operators WAN networks including many new service providers –2M and STM-N is widely used as leased lines including ATM/IP/DSL backbone networks

14 SDH Protocol

15 SDH Protocol - Multiplexing Multiplexing PDH signals –Plesiochronous multiplexing using bit stuffing Multiplexing SDH signals –Synchronous Multiplexing using Pointer Processing

16 SDH ramme, hastigheder og funktionalitet Time Division Multiplexing (TDM) SDH på 5 min

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18 SDH Protocol - Multiplexing Multiplexing PDH signals –Plesiochronous multiplexing using bit stuffing Multiplexing SDH signals –Synchronous Multiplexing using Pointer Processing

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21 SDH Protocol AU-4 Pointer Adjustment

22 SDH Protocol - Multiplexing Multiplexing PDH signals –Plesiochronous multiplexing using bit stuffing Multiplexing SDH signals –Synchronous Multiplexing using Pointer Processing Multiplexing Structure –Adaptation of PDH and other signals

23 SDH protocol - Multiplexing Structure

24 SDH mapping scheme Initial mappingMore MultiplexingContiguous Concatenation 24 C-4-64c C-4-256c C-4-16c C-4-4cAU-4-4cVC-4-4c AU-4-16cVC-4-16c AU-4-64cVC-4-64c AU-4-256cVC-4-256c x 1 AUG-64 AUG-256 AUG-16 AUG-4 STM-256 STM-64 STM-16 STM-4 x 1 x 4 C-4 C-3 C-2 C-12 C-11VC-11 VC-12 VC-2 VC-3 TUG-2TU-2 STM-0 AUG-1 VC-3 TUG-3 VC-4 AU-3 TU-11 TU-3 AU-4STM-1 x 1 x4 x 3 x 7 pointer processing multiplexing aligning mapping x 3 TU-12

25 SDH Equipment

26 SDH Equipment DXC 4/1 Interfaces: 2M, 34M, 45M, 140M, STM-1, (STM-4/16) XC matrix scaleable up to 32/128/256 STM-1 equivalent, non- blocking ADM 4/1 Aggregate Tributary Aggr. Interfaces: STM-1/4/(16) Trib. interfaces: 2M, 34M, 45M, 140M, STM-1/(4) ADM 4/4 Aggregate Tributary Aggr. Interfaces: STM-4/16/64 Trib. interfaces: STM-1/4/16 No access to lower order signals SDH på 5 min Regenerator function REG

27 ADM 4/1 STM-4 example

28 ADM 4/4 STM-64 example

29 SDH Networks

30 SDH Networks Hierarchical example

31 Network Structures - Pros and Cons StructureProsCons ChainFiber effective Simple nodes Low start cost Low connectivity No redundancy P2P upgrade costly RingFiber effective Simple nodes Redundancy Low connectivity P2P upgrade very costly MeshHigh connectivity Redundancy Cost efficient P2P upgrade Fiber consuming Complex nodes

32 SDH Networks - example, Routing in a hierarchical Network

33 SDH Networks add on SDH netstruktur

34 International Network structure

35 SDH networks - fiber infrastructure

36 SDH networks - WDM

37 SDH networks - STM-64

38 SDH networks - STM-16

39 SDH networks - VC-4

40 SDH Network node example SDH netstruktur

41 SDH network Optical cards and application codes STM16: –S16.1 (short haul, 1300 nm, 10 km) –L16.1 (long haul, 1300 nm, 20 km) –L16.2 (long haul, 1550 nm, 80 km) –V16.2 (very long haul, 1550 nm, 120 km) –U16.2 (ultra long haul, 1550 nm, 160 km) –L16.2 colered interface til WDM rel 1.0 –L16.2 colered interface til WDM rel. 3.0

42 Standards 42 Concatenation, Protocols etc. Link Capacity Adjustment Scheme (LCAS) Generic Framing Procedure (GFP) Equipment Equipment Management Function G.707 (10/2000) corr 1, corr 2*, add 1* G.7042/Y.1305 (11/2001)* G.7041/Y.1303 (11/2001)* G.783 (02/2001)* G.709 (02/2001) G.798 (11/2001) ITU-T

43 SDH Network Management

44 En netteknologi f.eks. SDH Network Manager SDH Network Management Network & Service Management View Network Manager Network Elements Element Manager Element Manager SM funktion #1 Technical administrative systems (inventory) planning modelling registration Element Level Management Network Level Management Service Level Management Subnetwork Manager Subnetwork Manager Bussines Level Management Network Elements Element Manager Element Manager Subnetwork Manager Subnetwork Manager SM funktion #2 Costumer administrative systemsCustomer acces/ applikationer Funktions: Provisionering Performance Assurance Alarmmanager

45 SDH Network Management Element Manager –Matrix: 48 ports 4/4 non-blocking, dubleret

46 SDH Network Management DCN, Data Communications Network is needed

47 Sub-Network Level: NEs Level: NE GUI Double click SDH Network Management Network Manager Point and click management 6 levels subnetwork nesting

48 Fault Management /Service Management Filter via tree view

49 SDH Services

50 SDH Services Leased line Services (fixed dedicated bandwidth): –2 Mbit/s, n x 2 Mbit/s –VC-12, n x VC-12 –34 Mbit/s, 45 M Mbit/s –VC-3, n x VC-3 –140 Mbit/s –VC-4 –VC-4-4c, VC-4-16c –Grey fibres / WDM channels add-on services –Alternative routing, Specific routing, automatic protection, various Service Level Agreements (SLAs)