10/10/ DSL, CM, SONET - Lin 1 CPET/ECET High Speed Access Digital: DSL, Cable Modem, SONET Data Communications and Networking Fall 2004 Professor Paul I-Hai Lin Electrical and Computer Engineering Technology Indiana University-Purdue University Fort Wayne
10/10/ DSL, CM, SONET - Lin 2 High-Speed Access: DSL, Cable Modem and SONET 1.DSL (Digital Subscriber Line) Technology ADSL (Asymmetric) Discrete Multitone Modulation SDSL (Symmetric) HDSL (High-bit rate DSL) 2.Cable Modem CATV (cable) HFC (Hybrid Fiber Coax) Network DOCSIS (Data over Cable System Interface Specification) 3.SONET SONET devices SONET Frame and Rates
10/10/ DSL, CM, SONET - Lin 3 DSL Technology DSL Categories –ADSL (Asymmetric) –SDSL (Symmetric) –HDSL (High-bit rate DSL) –VDSL (Very-high bit rate DSL)
10/10/ DSL, CM, SONET - Lin 4 DSL Technology Lowest 4 kHz for voice lines Twisted-pair local loop – up to 1.1 MHz Uses Discrete Multi-Tone Modulation (DMT, QAM + FDM) Upstream speed < Downstream speed Fast business users Mbps/512kbps Residential users – 512/64 Kbps –UTP wires – support BW up to 1.1 MHz –Upstream 30 kHz to * –Downstream * to 1.1 MHz Info: htm htm
10/10/ DSL, CM, SONET - Lin 5 Discrete Multitone Technique From p. 220, Figure 9.1 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 6 DSL Bandwidth Division From p. 221, Figure 9.2 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 7 Discrete Multitone Technique DMT – uses QAM and FDM Divide MHz into 256 channels, each KHz Channel 0 – Voice Channel 1-5 (Band Guard, unused) Channel 6 to 30 (24) –Upstream data –QAM – 15-bit/baud –Date rate: 24 x 4000 x 15 = 1.44 Mbps Channel 31 to 255 (225) –Downstream data –Data rate: 225 x 4000 x 15 = 13.4 Mbps Actual Bit Rate –Upstream: 64Kbps to 1 Mbps –Downstream: 500 Kbps to 8 Mbps
10/10/ DSL, CM, SONET - Lin 8 ADSL Modem From p. 222, Figure 9.3 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 9 DSL Access Multiplexer From p. 222, Figure 9.4 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 10 Other DSL Technologies SDSL (Symmetric DSL) –Business HDSL (High-bit-rate DSL) –Alternative to T1 (1.544 Mbps) –3.6 km VDSL (very-high-date-rate DSL) –300 to 1800 m –Downstream: 50 to 55 Mbps –Upstream: 1.5 to 2.5 Mbps
10/10/ DSL, CM, SONET - Lin 11 Cable Modem Community Antenna TV (CATV) Hybrid Fiber-Coax Network Bandwidth Data rates Cable Modem Cable Modem Transmission System Data Transmission Scheme
10/10/ DSL, CM, SONET - Lin 12 Traditional Cable TV Network From p. 223, Figure 9.5 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 13 Hybrid Fiber-Coax Network Fiber + Coax Regional Cable Head (400 K subscribers) Distribution Hub (40 K subscribers) Switch Fiber –Fiber Links –Fiber Nodes Coaxial Distribution (Drop cable – about 1000 subscribers) Data Streams –Upstream Fiber –Downstream Fiber
10/10/ DSL, CM, SONET - Lin 14 HFC Network From p. 224, Figure 9.6 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 15 Cable TV Bandwidth Allocation From p. 225, Figure 9.7 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 16 Cable TV Bandwidth Allocation From p. 225, Figure 9.7 of Data Communications and Networking, Forouzan, McGrawHill Data Upstream: –5 MHz to 42 MHz (6 channels, 6 MHz/channel) –12 Mbps (2-bit/Hz QPSK x 6MHz) –TDM sharing among neighborhood Analog TV Bands: 54 MHz to 500 MHz (80 ch x 6 MHz/ch) Digital video and Data Downstream –550 MHz to 750 MHz (180 channels) –64-QAM (6-bit, 5-bit/Hz x 6MHz = 30 Mbps)
10/10/ DSL, CM, SONET - Lin 17 Cable Modem From p. 227, Figure 9.8 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 18 Cable Modem Transmission System From p. 227, Figure 9.9 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 19 Data Over Cable System Interface Specification (DOCSIS) 1. The CM checks the downstream channels (sent by the CMTS) 2. The CMTS allocate up/down BW for the CM 3. The CM determines the distance between the CM and CMTS – synchronization, minislots (TDM) 4. The CM asking for Internet addresses 5. The CM and CMTS establish the security parameters 6. The CM sends its ID to CMTS 7. Upstream communication begin
10/10/ DSL, CM, SONET - Lin SONET Two Standards –ANSI - Synchronous Optical Network –ITU-T standard – Synchronous Digital Hierarchy (SDH) Features –Synchronous network: A single clock (timing), data frame, multiplexed Fiber-optics transmission system (FOTS) standard Physical design – carrying signals from incompatible systems (DS0 and DS-1) –TDM system
10/10/ DSL, CM, SONET - Lin 21 SONET Devices Synchronous Transport Signal (STS) Multiplexer/Demultiplexer Regenerator (repeater) Add/Drop Multiplexers
10/10/ DSL, CM, SONET - Lin 22 A SONET From p. 229, Figure 9.10 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 23 SONET Frame From p. 230, Figure 9.11 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 24 SONET Frame A frame –Total 810 octets = 9 rows x 90 octets per row –Administrative overhead 27 octets = 3 columns x 9 rows –The first 2 bytes: alignment byes (F628), begin a frame –Synchronous Payload Envelop (SPE) Transmission overhead User data
10/10/ DSL, CM, SONET - Lin 25 SONET Rates STS (Sync. Transport Signals) Levels –STS-1 to STS-192 –Physical link called Optical Carriers (OCs) STS-1 (OC-1) –8000 frames/sec –810 octets per frame –Raw rate = 8000 x 9 x 90 x 8 = Mbps –SPE rate = 8000 x 9 x 87 x 8 = Mbps –User rate = 8000 x 9 x 86 x 8 = Mbps
10/10/ DSL, CM, SONET - Lin 26 Table SONET Rates STSOCRate (Mbps)SPE (Mbps)User (Mbps) STS-1OC STS-3OC STS-9OC STS-12OC STS-18OC STS-24OC STS-36OC STS-48OC STS-192OC From p. 231, Table 9.1 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 27 Virtual Tributaries A particular payload that can be inserted into a frame and combined with other payloads to fill out the frame VT1.5 accommodates DS-1 (1.544 Mbps) VT2 – European CPET-1 (2.048 Mbps) VT3 – DS-1C (3.152 Mbps) VT6 – DS-2 (6.312 Mbps)
10/10/ DSL, CM, SONET - Lin 28 Virtual Tributaries Types From p. 232, Figure 9.13 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 29 Higher-Rate Services From p. 232, Figure 9.14 of Data Communications and Networking, Forouzan, McGrawHill
10/10/ DSL, CM, SONET - Lin 30 Summary Questions?