ECEN5553 Telecom Systems Dr. George Scheets Week 11 Read [25] All Smart, No Phone [26a] "A Surge in Small Cells" [26b] "Riding the Data Tsunami in

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1 ECEN5553 Telecom Systems Dr. George Scheets Week 11 Read [25] All Smart, No Phone [26a] "A Surge in Small Cells" [26b] "Riding the Data Tsunami in the Cloud" Exam #2 (Internet thru Fiber Optic Systems) 28 October < 4 November (Distant Learning) Term Paper 6 November (Live) 13 November (Distant Learning

2 Term Paper Reminders Statement not "Common Knowledge"? Cite in Main Body of the Paper Don't plagiarize! Copied word for word? Cite it & put in "quotes". Don't cut & paste, and then change a few words. Probe Further Don't Get too Bubbly Watch out for dated references Good Score Good Read, Factually Correct, Follows Outline Feel Free to have someone proofread your paper

3 Paper Delivery No Paper Copies Submit Electronically via or D2L... Word Perfect Word Writer (Open Office).odf files PDF

4 Web Citations Provide sufficient info so I can pull up your article!! Use common sense. site/directory/filename is best (include author, title, year if available) Don't just put site author, title, journal, year (available at Search Engine XYZ) is fine Beware the long URL generated by search engines Sometimes they work. Sometimes they don't.

5 Fiber Capacity Growth Source: High-Capacity Optical Transport Networks, IEEE Communications, November 2012

6 Modulation Up to 10 Gbps, typically OOASK On-Off Amplitude Shift Keying Detecting presence or absence of a light pulse 40 Gbps, starting to see phase modulation Differential Phase Shift Keying (DPSK) Better BER than straight OOASK 100 Gbps, starting to see Coherent Detection More sophisticated, better BER than DPSK

7 Average Delay Design Dilemma: Revisited Average Offered Trunk Load Bandwidth Glut - WDM is keeping this option alive Keep Trunks Lightly Loaded Use simple Routers/Switches (FIFO) All StatMux traffic has low delays.

8 Average Delay Design Dilemma: Revisited Low Priority Average High Priority Bandwidth Crunch Offered Keep Trunks Heavily Loaded Trunk Load Use complex Routers/Switches Prioritize Traffic High Priority Delays identical to BW Glut.

9 Mortal Enemy of Buried Fiber Oops!

10 From/To OKC TUL DET NYC OKC TUL DET NYC Line Switched Ring Affected traffic treated as indivisible entity. 1+2 OKC TUL NYC X 5+6 DET

11 From/To OKC TUL DET NYC OKC TUL DET NYC Line Switching NYC Tulsa Traffic Now Inefficiently Routed NYC OKC TUL NYC 5+6 X 5+6 DET

12 From/To OKC TUL DET NYC OKC TUL DET NYC Path Switching Affected Flows Individually Rerouted NYC OKC TUL NYC X 5+6 DET

13 Failure Analysis/Survivability Suppose LA Dallas link fails Paths Paths Paths Paths 121+ Paths Suppose LA Denver Traffic routed as shown. Figure 1) 17 Node, 27 Link Test Network with 500 End-to-End Optical Paths. Links are color coded based on traffic density.

14 Failure Analysis/Survivability If Line Protection, the affected Line's traffic is rerouted around break. Rerouted LA Denver Paths Paths Paths Paths 121+ Paths Figure 1) 17 Node, 27 Link Test Network with 500 End - to - End Optical Paths. Links are color coded based on traffic density.

15 Failure Analysis/Survivability LA Denver Paths Paths Paths Paths 121+ Paths Figure 1) 17 Node, 27 Link Test Network with 500 End-to-End Optical Paths. Links are color coded based on traffic density.

16 Anaheim - Dallas Fails Example here is Path Protection. All affected city pairs are rerouted. Note changes in NE. Rerouted LA Denver. X 1-30 Paths Paths Paths Paths 121+ Paths Figure 2) Link Traffic Intensity after failure of the Anaheim - Dallas link. 500 End-to-End Optical Paths.

17 Line vs Path Protection Line Protection is faster Treats affected traffic as indivisible Reroutes all flows over same links Affects fewer network switches Requires more spare BW Path Protection is slower Reroutes each individual flow May affect most all network switches Requires less spare BW

18 Note that The Internet has no specified Physical Layer... 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical TCP TCP IP

19 On the WAN, SONET/OTN fits the bill! 5 Session 4 Transport 3 Network 2 Data Link 1 Physical TCP TCP IP SONET/OTN SONET/OTN LAN: Ethernet MAN: T-Carrier, SONET/OTN, & Ethernet

20 SONET Ring Physical Network OSI Level 1 & 2 SONET ADMs & Cross-Connects Fiber Optic Cables in the ground (up to 40 Gbps per SONET λ)

21 ISP Backbone (Logical Network) OSI Level Note Logical connection between router 1 & ISP Routers

22 ISP traffic riding on a SONET Ring OSI Level 1 & Physical fiber optic cables might be connected as shown.

23 ISP traffic riding on a SONET Ring OSI Level 1 & 2 1 X Router trunk circuits may ride over the SONET network as shown. SONET trunks dedicate time slots to each trunk.

24 ISP Backbone (Logical Network) OSI Level 3 1 X 2 X Note Logical connection between router 1 & ISP Routers

25 SONET/OTN is Important on the WAN Internet, OSI Layer 3 Needs something at Layer 1 (& 2) Carrier Ethernet, OSI Layer 1 & 2 Not "Carrier Grade", Insufficient OAM T1 & T3 Leased Lines sold end-to-end T1 (twisted pair) & T3 (coax) on last mile SONET time slots on long haul SONET Layer 2 importance decreasing SONET is circuit switched TDM geared towards voice Optical Transport Network faster & more packet friendly IEEE Resilient Packet Ring

26 OSU 2009 Internet Connectivity

27 POTS Connectivity Copper Local Loop CO Fiber Optic Trunk CO Copper Local Loop Phone Phone 4 Wire 2 Wire 4 Wire 2 Wire 4 Wire Analog Digital 64 Kbps TDM Analog

28 Phone POTS Connectivity (ISDN) All-Digital Phone System V1.0 Copper Local Loop CO Fiber Optic Trunk CO Copper Local Loop Phone 4 Wire 2 Wire 4 Wire 2 Wire 4 Wire Digital 64 Kbps

29 Integrated Services Digital Network Basic Rate Interface (BRI) Aimed at typical home users, SOHO crowd Provides 2 x 64 Kbps Bearer Channels... Phone & Computer usage... & 16 Kbps signaling channel. Looked good in early '90's Compared to a 14.4 Kbps dial up modem RBOC's deployed ISDN capable switches slowly.

30 ISDN SBC was gearing up to push this in mid '90's. Then... Internet use exploded DSL came along BRI = Too Little, Too Late Voice calls will eventually be all-digital, but not as envisioned with ISDN VoIP or VoMPLS

31 ISDN Primary Rate Interface (PRI) Aimed at medium to large business Provides 23 x 64 Kbps Bearer Channels & 64 Kbps signaling channel. Has seen more success. Reasonably common way to connect corporate PBX to PSTN [19c] "SIP Trunking: The Savings Are There But Transition is Complex" Covers transition from PRI to Internet SIP Trunking

32 All-Digital Phone System V2.0 IP Phone LAN Router ISP Router LAN IP Phone Digital,?? Kbps

33 All-Digital Phone System V3.0 ISP Cell Phone Router Router Cell Phone Digital,?? Kbps

34 Radio Frequency Facts Wavelength = Propagation Speed = λ Frequency Rule of Thumb: As antenna size > 1/4 wavelength, EM radiation becomes significant. Small antennas require high frequencies

35 Power Spectrum 1 MHz Sinusoid 1 vp 1 MHz ,000,000 freq (Hertz)

36 1 MHz EM Wave An oscillating Electric voltage, connected to an antenna via a cable, will cause an Electro-Magnetic field to radiate away at nearly 3*10 8 m/sec. Analogy: Waves radiating from pebbles continually being dropped at the same location into a pond. 1 MHz Sinusoid Source

37 1 MHz EM Wave 300,000,000 meters/second 1 MHz Sinusoid Source EM wave will radiate in all directions. Propagates at near speed of light in a vacuum. Shown: Electric Field propagating to right. Not shown: Electric field in other directions. Not shown: Magnetic Field

38 1 MHz EM Wave 300 meters Situation at t = 0 1 MHz Sinusoid Source = 675m Field Strength Meter 375m

39 1 MHz EM Wave 300 meters Situation at t = seconds 1 MHz Sinusoid Source = 675m Field Strength Meter 375m

40 RF Free-space Power Loss vs Optical Fiber Power Loss RF. RF Loss proportional to distance 2 Fiber 0 0 1,000 m distance Fiber Loss = Free Space Laser & Copper Cabling normally fall between these extremes.

41 EM Waves and You MHz GHz THz PHz EHz Solids: Glass: Concrete Similar Wood Metal: except Blocks around Similar everything. visible Effect. Gamma light & can infrared. punch thru thin sheets. source:

42 Atmospheric Absorption source:

43 Do Cell Phones Cause Brain Cancer? Studies in [24b] show mixed results Some show increased chances Some show decreased chances World Health Organization says maybe Laws of Physics & Frequencies Used Today Localized "Heating" possible 1 watt cell by ear? 1/2 watt hits head. Oklahoma Mesonet, 2:50 pm, 31 October watts/meter 2 solar radiation falling (hazy) Top of Dr. Scheets' head 0.03 meters watts of solar radiation hit top

44 Radio Transmission Want a reasonable size antenna? λ (= velocity/frequency) needs to be small Signal needs high frequencies Injecting pulses directly into antennas? Won't work well All pulses have a lot of low frequency energy Won't radiate well Need to shift all pulse's energy to higher frequency range

45 Power Spectrum 1 MHz Sinusoid vp 1 MHz ,000,000 freq (Hertz)

46 Binary ASK MHz Two different Amplitudes are transmitted 10 cycles/ seconds = 1 MHz 5 cycles/symbol 200 K symbols/second = 200 K bits/second

47 Binary FSK Two different frequencies are transmitted Symbol #1) 5 cycles/ seconds = 1 MHz Symbol #2) 10 cycles/ seconds = 2 MHz 1.5 MHz Average (center) Frequency 2 symbols in seconds = 200 K symbols/second = 200 K bits/second

48 Binary PSK MHz Two different phases are transmitted 10 cycles/ seconds = 1 MHz 5 cycles/symbol 200 K symbols/second = 200 K bits/second

49 M-Ary Signaling One of M possible signals transmitted each symbol interval Tends to be used where bandwidth is tight & SNR decent at the receiver. Each symbol can represent log 2 M bits Example: In 16 FSK one of 16 possible frequencies is transmitted every symbol interval each symbol can represent 4 bits

50 4-Ary ASK MHz different Amplitudes are transmitted (3 shown) 4th symbol might be 0 volts for 5 μ seconds 15 cycles/ seconds = 1 MHz 5 cycles/symbol 200 K symbols/second = 400 K bits/second

51 Quadrature Amplitude Modulation (form of M-Ary Modulation) MHz Different amplitudes and phases are transmitted 15 cycles/ seconds = 1 MHz 5 cycles/symbol 200 K symbols/second = Log 2 M*200 K bits/second

52 Unfiltered b Spectrum

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