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Access Network Technologies by Mind Map: Access Network Technologies


1.1. WiMAX

1.2. LTE

2. Performance

2.1. High-speed

2.2. High-sensitivity

3. provides network connectivity over wireless media

4. FSO

4.1. Outdoor Deployment

4.1.1. Smog

4.1.2. Rain

4.1.3. Snow

4.2. Indoor Deployment

5. Duplexing

5.1. Time division duplexing (TDD)

5.2. Frequency division duplexing (FDD)

6. Multiple Access

6.1. Frequency Division Multiple Access (FDMA)

6.1.1. One circuit per channel at a time

6.1.2. Channel is normally narrow bandwidth (30kHz for AMPS)

6.1.3. Transceiver complexity is lower compared to TDMA

6.1.4. Fewer overhead bits

6.2. Time Division Multiple Access (TDMA)

6.2.1. TDMA is a multiplexing method that divides network connections into time slices. The TDMA digital transmission scheme multiplexes three signal over a single channel Often used to refer digital mobile phone networks TDMA allows many users to access a single RF channel without interference by allocating unique time slots to each user within each channel.

6.2.2. TDMA Advantages To increase the efficiency of transmission Can be easily adapted to the transmission of data as well as voice communication Most cost effective technology for upgrading analog to digital It is the only technology that offers an efficient utilization of hierarchal cells structures like pico, micro and macro cells.

6.2.3. TDMA Disadvantages Each user has a predefined time slot. It is subjected to multipath distortion.

6.2.4. How TDMA Works It relies upon the fact that the audio signal has been digitized where it divided into a number of ms-long packets. It allocates a single frequency channel for a short time and then moves to another channel The digital samples, from a single transmitter occupy different time slots in several bands at the same time

6.3. Orthogonal Frequency Division Multiple Access (OFDMA)

6.3.1. OFDMA is a multi-user version of the popular orthogonal frequency-division multiplexing digital modulation scheme.

6.3.2. Advantages of OFDMA is the deployment is flexible across many frequency bands with few modification to the air interfaces. It is also uses allocation with cyclic permutation which only has average interference within the cell. Furthermore, it is provides frequency diversity just by spreading the carriers all over the used spectrum. It also offers per-channel or per-subchannel power.

6.4. Spread Spectrum Multiple Access

6.4.1. Frequency Hoped Multiple Access (FHMA) The frequency can be adjusted in a pseudorandom sequence between several discrete radio channels Various user can use same spectrum Slow frequency hopping system if rate of change of carrier frequency is lower than symbol rate Fast frequency hopping system if rate of change of carrier frequency greater than symbol rate Example: Bluetooth & HomeRF

6.4.2. Direct sequence spread spectrum multiple access (DSSS) / code division multiple access (CDMA)

6.5. Pure ALOHA

6.5.1. Does not require slots

6.5.2. Send a frame whenever there is a frame

6.5.3. Does not require global time synchronization

6.5.4. Vulnerable time of 2 x Tfr

6.5.5. Throughput is reduced by one half. e.g : S=(1/2e)

6.6. Slotted ALOHA

6.6.1. Invented to improve efficiency of Pure ALOHA

6.6.2. Require slot synchronization

6.6.3. Send frame only at the beginning of the time slot

6.6.4. Detect collision slotted if multiple nodes transmit

6.6.5. Does require global time synchronization

6.6.6. Divide time into slot Tfr

6.6.7. Throughput for slotted ALOHA is S = G x G-e

7. Free Space Optics (FSO)

7.1. Definition

7.1.1. Also called Free Space Photonics (FSP) or Optical Wireless, refers to the transmission of modulated visible or infrared (IR) beams through the atmosphere to obtain optical communications.

7.2. How does it works?

7.2.1. Uses laser technology to send optical signals through the air using lenses and mirrors to focus and redirect the beams and send data from one chip to another. Consists of optical transmitter and receiver

7.3. Advantages

7.3.1. no interference

7.3.2. Does not require spectrum license

7.3.3. Installation cost is lower compared to laying Fiber

7.3.4. Low power consumption

7.3.5. easily upgradeable

7.4. Disadvantage

7.4.1. support only point to point communication

7.4.2. atmospheric attenuation

7.4.3. scintillation

7.4.4. signal scattering results in multipath impairment

7.4.5. susceptible to loss & natural impediment (rain, haze, fog, obstruction)


8.1. WIreless Local Area Network

8.1.1. uses radio waves as its carrier

8.1.2. IEEE 802.11 standard

8.1.3. covers Physical and Data Link Layers

8.2. Access Point (AP)

8.2.1. act as bridge between Wireless and Wired Network

8.2.2. provides access to the Distribution System (DS)

8.3. WLAN Topology

8.3.1. Infrastructure Mode Mobile stations (MS) is connected to AP AP is connected to wired network

8.3.2. Ad-Hoc Mode No AP required A number of MS form a cluster to make a network

8.4. How it works?

8.4.1. using the same networking protocols and supporting most of the same applications.

8.4.2. specialized physical and data link protocol

8.4.3. integrate into existing network through AP which provide a bridging function

8.4.4. stay connected as it roam from one coverage area to another

8.5. advantages

8.5.1. Mobility:

8.5.2. Fast setup

8.5.3. Higher cost

8.5.4. Expandability

8.6. Disadvantages

8.6.1. Interference

8.6.2. Inconsistent connections

8.6.3. Uses more power consumption

8.6.4. Lower speed

9. Optical Fiber Technology

9.1. Definition

9.1.1. medium and the technology associated with the transmission of information as light pulses along a glass or plastic strand or fiber

9.2. Working Principle

9.2.1. Transmit data in the form of light particles or photons that pulse through a fiber optic cable using the process called total internal reflection

9.3. Types of Fibers

9.3.1. SMF Definition Single Mode Fiber optic cable has a small diameter core that allows only one mode of light to propagate Advantages Increase bandwidth capacity Better performance in long runs transmission Limited Data Dispersion & External Interference Fast transmission speed Disadvantages High cost Application Best choice for transmitting data over long distance Used for connections over large areas such as college, campuses and remote offices

9.3.2. MMF Definition Multimode Fiber optic cable has a large diametral core that allows multiple mode of light to propagate Advantages Less expensive Easier to work with other optical components Allows several mode optical signals transmitted at the same time Good alignment tolerances due to large fiber core Disadvantages High dispersion and attenuation rate Applications Good choice for transmitting data and voices signals over shorter distance Used for data and audio/visual application in local area networks and connections within buildings or remote office in close proximity to one another.


10.1. signal travels over the air directly from a wireless transmitter to a wireless receiver without passing an obstruction.

10.1.1. reach longer distance with better signal strength and higher throughput

10.1.2. example of LOS Microwave point to point communication point to point connection between BS and SS.

10.1.3. Application Building to building connectivity Fiber line replacement Wireless failover

10.2. Opposite to NLOS

10.2.1. NLOS- signal from a wireless transmitter passes several obstructions before arriving at a wireless receiver. example of NLOS Wireless connection between BS (Base Station) and SS (Subscriber station) application Public Wi-Fi Campus wide broadband Locations that can't be cabled Stadiums and exhibitions halls WiMAX

10.3. LOS vs NLOS

10.3.1. similarities operate in both unlicensed and licensed frequencies bands.

10.3.2. difference LOS point to point NLOS point to multipoint

11. HFC Network

11.1. Why used HFC

11.1.1. To carry broadband contents (Video, Audio, Data)

11.1.2. Increase Transmission Range

11.1.3. Maintain Superior performance

11.2. Advantages

11.2.1. Reduce power consumption

11.2.2. Simplification of the maintainance

11.2.3. Increase RF bandwidth

11.2.4. Improve Reliability

11.2.5. Improve QoS and potential terminal cost reduction

11.3. Disadvantages

11.3.1. Not fully installed

11.3.2. Expensive

12. WMAN

12.1. WHAT IS WMAN ??

12.1.1. - Short form from Wireless Metropolitan Area Network - Connection of several WLAN - Has an intended coverage are Two types of WMAN Back Haul Last Mile

12.2. Underwater FSO

12.2.1. Definition FSO underwater is an optical communication technology that utilized the use of laser diode or light emitting diode, LED to transmit or receive data information, voice and video through underwater

12.2.2. Current Technology Optical wireless Acoustic wave Radio Frequency

12.2.3. Medium Laser Diode Long Distance Low Spectral Width High Data Rate Transmission High Output Power High Operating Cost Light Emitting Diode LED Short Distance High Spectral Width Low Data Rate Transmission Low Output Power Low operating cost

12.2.4. Features FSO System Length 50-150 m Attenuation 0.39-11.0 db/m Bandwidth 0.8 nm Operating Wavelength 405 nm

12.2.5. Advantages High Data Transmission Lower Attenuation Easy to install Lower Error Rate


12.3.1. An outdoor, point to point WLAN


12.4.1. ADVANTAGES - Simple and easy to distinguish - Less costing than fiber-based LANs

12.4.2. DISADVANTAGES - Large area for hacker to attempt a break in


12.5.1. Security Vulnerability No two way authentication Weak curyptographic Reuse TEK

13. FiWi Network

13.1. Free Space Optics (FSO)

13.1.1. Working Principle Deploying either a high-power light emit-ting diode(LED) or a laser diode, while the receiver may deploy a simple photo detector

13.1.2. Importance FSO offers high bandwidth and reliable communication over short distance convenience High speed Security

13.2. Radio over Fiber (RoF)

13.2.1. Working Principle Light is amplitude modulated by a radio signal and transmitted over an optical fiber link to facilitate wireless access

13.2.2. Importance Low attenuation Loe complexity Low cost Future proof

14. DWDM

14.1. Definition

14.1.1. up to 80 (and theoretically more) separate wavelengths or channels of data can be multiplexed into a light stream transmitted on a single optical fiber.

14.2. DWDM System Components

14.2.1. Optical Transmitters/Receivers

14.2.2. DWDM Mux/DeMux Filters

14.2.3. ptical Add/Drop Multiplexers (OADMs)

14.2.4. Optical Amplifiers

14.2.5. Transponders (Wavelength Converters)

15. GPON vs HFC

15.1. Similarity

15.1.1. system use same RF video transmitter

15.2. Differences

15.2.1. System Bandwidth

15.2.2. Operating & Maintenance Costs

15.3. Advantages of GPON over HFC

15.3.1. Smaller node size

15.3.2. Reduce operations and maintenance costs

15.3.3. Great transmission capacity with dedicated wavelengths for:- Upstream, Downstream Downstream cable-TV overlay

16. Peer to Peer Network

16.1. Advantages

16.1.1. Low cost

16.1.2. Simple to configure

16.1.3. User has full accessibility of computer

16.2. Disadvantages

16.2.1. May have duplication in resources

16.2.2. Difficult to handle uneven loading

16.2.3. Difficult to uphold security policy.

16.3. Where p2p network is appropriate

16.3.1. 10 or less user

16.3.2. No specialized service required

16.3.3. Security is not an issue

16.3.4. Only limited growth foreseeable future

17. WiMAX

17.1. definition

17.1.1. Worldwide Interoperability for Microwave Access is a technology standard for long-range wireless networking, for both mobile and fixed connections.

17.2. elements

17.2.1. Base Station

17.2.2. Subscriber station

17.3. pros & cons

17.3.1. pros Higher coverage range cheaper alternative to broadband wired technologies

17.3.2. cons LOS high speed voice and data transfer over longer distances. power consuming technology and requires significant electrical support higher initial costs and higher operational costs

17.4. differences between WiMAX and WLAN(WiFi)

17.4.1. WLAN can deliver much faster speeds compared to WiMAX

17.4.2. WiMAX is meant for long range applications while WLAN is meant for short range applications.

17.4.3. WiMAX provides a much better method of bandwidth distribution compared to WLAN.


18.1. a method of combining multiple signals on laser beams at various wavelengths for transmission along fiber optic cables

19. Added Bandwidth Distribution and Protection


20.1. cable television networks

20.2. metropolitan networks

21. Pseudorandom binary sequence (PRBS)

22. BER Testing

22.1. Quasi-random signal source (QRSS):


23.1. XG-PON

23.1.1. G.987.1

23.1.2. 10Gbps downstream & 2.48Gbps for upstream

23.1.3. Improvement Security Mechanism Power Saving Option Power Shedding Enabling Mobile Backhauling ODN enhancement performance monitoring

23.1.4. Transmission Capabilities TDMA Split ratio 1:256 20km distance Optical source: 1310nm/1490nm

24. FTTx

24.1. PON

24.1.1. APON Built on ATM

24.1.2. BPON

24.1.3. EPON Uses Ethernet Packet

24.1.4. GPON High Speed and Power Saving

25. DSL (Wired)

25.1. Voice

25.1.1. PSTN/POTS Hierarchy Architecture Star Structure

25.2. Data

25.2.1. Symmetric SDSL ISDN DSL High Bit Rate DSL

26. PLC (no new wires)

26.1. How?

26.1.1. Outdoor

26.2. Asymmetric

26.2.1. ADSL

26.2.2. VDSL

26.2.3. RADSL

26.2.4. G.Lite

26.3. Network Level?

26.3.1. Medium Voltage

26.3.2. High Voltage

26.3.3. Low Voltage

26.3.4. In Home

26.4. Modulation Scheme?

26.4.1. OFDM Definition The main concept of OFDM is orthogonality of the sub-carriers. The orthogonality allows simultaneous transmission on a lot of sub-carriers in a tight frequency space without interference from each other. Advantages i.) can easily adapt to severe channel conditions without complex time dome equalization ii) Robust against narrow-band co-channel interference iii) Robust against intersymbol interference (ISI) and fading cause by multipath propagation. iv) High spectral efficiency v) Low sensitivity to time synchronization errors. Disadvantages i) High peak-to-average-power-ratio (PAPR), requiring linear transmitter circuitry, which suffer from poor power efficiency. ii) Sensitive to frequency synchronization problem iii) Loss efficiency caused by cyclic prefix iv) Sensitive to Doppler shift

26.5. Channel?

26.5.1. Shared channel like Wifi

26.6. Protocols?

26.6.1. X-10

26.6.2. CE-Bus

26.6.3. Lon-Works

26.6.4. Home Plug 1.0

26.6.5. Home Plug AV

27. Bit Error Rate (BER)

27.1. Number of bit error

27.2. Error rate per unit time of the received bits.

27.3. One of the key parameters as assessment

27.4. Factors affecting BER

27.4.1. Interference

27.4.2. Increase transmitter power

27.4.3. Lower order modulation

27.4.4. Reduce bandwidth

27.5. Formula-->> Number of error / Total bits sent

28. WiMAX Quality of Services (QoS) Classes

28.1. Unsolicited Grant Service (UGS)

28.1.1. support real-time data stream issued at periodic interval

28.1.2. Example : VoIP

28.2. Real-time Polling Services (rtPS)

28.2.1. support real-time streams consisting variable-sized data packet

28.2.2. Example : MPEG video

28.3. Non real-time Polling services (nrtPS)

28.3.1. support delay-tolerant data streams consisting of variable-size data packets for a minimum data rate required

28.3.2. If the hub fails, whole network is stopped

28.3.3. Example : FTP transmission

28.4. Parameter used to describe WiMAX QoS

28.4.1. Latency Measure in time delay in a system : time taken from initiation of sending data until it arrives its destination

28.4.2. Jitter Measure of the variability over time of the packet latency across a network

28.4.3. Packet Loss indicate the loss of data packets during transmission over a network

29. Network Topology

29.1. Star Topology

29.1.1. Pros Low network traffic Easy to troubleshoot Easy to setup and modify

29.1.2. Cons High installation cost Expensive to use

29.2. Mesh Topology

29.2.1. Pros Each connection can carry its own data load. High cabling cost Fault is diagnosed easily Provides security and privacy

29.2.2. Cons Installation and configuration are difficult

29.3. Ring Topology

29.3.1. Pros Cheap to install and expand Transmitting network is not affected by high traffic or by adding more nodes

29.3.2. Cons Troubleshooting is difficult in ring topology. Failure of one computer disturbs the whole network.

29.4. Wireless Mesh Network

29.4.1. Working Principle Self-Configuring Network automatically incorporates a new node into the existing structure without needing any adjustments by a network administrator Self-Healing Network automatically finds the fastest and most reliable paths to send data, even if nodes are blocked or lose their signal

29.4.2. Application Hospitality Warehouse Education Campus

30. Radio over Fiber (RoF)

30.1. Two main categories

30.1.1. RF-over Fiber

30.1.2. IF-over-Fiber

30.2. Advantages

30.2.1. Low attenuation

30.2.2. Low cost

30.2.3. Large bandwidth

30.2.4. Future proof

30.3. Challenges

30.3.1. Modulation technique

30.3.2. Chromatic dispersion

30.3.3. Phase distortion

30.3.4. High data rate wireless link as a complimentary part of RoF

30.3.5. Expensive and complex uplink

30.3.6. Noise characterization and cancellation for combination of optical and wireless noise

30.4. Application

30.4.1. Access to dead zones

30.4.2. FTTA (fiber to the antenna)

30.5. Current technologies by using RoF

30.5.1. IF over SMF and MMF

30.5.2. RF over SMF

31. Fttx (Fiber To The X)

31.1. Definitions

31.1.1. All possible optical fiber topologies from a telecom or cable carrier to its customers, based on the location of the fiber's termination point. FTTP/FTTH/FTTB (Fiber laid all the way to the premises/home/building) FTTC/N (fiber laid to the cabinet/node, with copper wires completing the connection)

31.2. Advantages

31.2.1. the demand for reliable bandwidth is crucial as more and more people begin to utilize these services.

31.2.2. Fibre to the All it mean we can provide any services Ex: Business, House, Buildings.

31.2.3. It has good speed and quality of net.

31.2.4. Fiber is often said to be "future-proof" because the data rate of the connection is usually limited by the terminal equipment rather than the fiber

31.3. Disadvantages

31.3.1. Installation costs, while dropping, are still high

31.3.2. Susceptibility to physical damage

31.4. Deployment of Fttx in Malaysia

31.4.1. Telekom Malaysia (TM) officially launched FTTH on 24 March 2010.

31.4.2. TM High Speed Broadband (HSBB) was released to end users in stages.

31.4.3. The deployment from start to the connection of the first end user to the fiber network took only 18 months, which is the fastest ever in the world.

31.4.4. The product name is UniFi and it initially offers speeds of 5, 10 and 20 Mbit/s under the VIP5, VIP10 and VIP20 brand name.The packages were later revised to UniFi Advance (30 and 50Mbit/s) and UniFi Pro (100Mbit/s).

31.4.5. The fiber network is also leased out to competitors Maxis Communications and Packet One Networks.

31.4.6. TIME Fibre Broadband which is Officially launched on 2 February 2010 is a true fibre optic connectivity to home with speeds of 100Mbit/s, 300Mbit/s, 500Mbit/s. Time offer the FTTx services to the apartment Condominium residential only.

32. Ethernet Passive Optical Network (EPON)

32.1. How does an EPON work?

32.1.1. In a EPON the process of transmitting data downstream from the OLT to multiple ONUs is fundamentally different from transmitting data upstream multiple ONUs to the OLT.

32.2. What Are EPON?

32.2.1. Ethernet passive optical networks (EPON) are an emerging access network technology that provides a low-cost method of deploying optical access lines between a carrier office (CO) and customer site

32.3. Downstream Traffic flow in an EPON

32.3.1. The data broadcasted downstream from OLT to multiple ONUs in variable-length packets of up to 1,518 bytes, according to IEEE 802.3 protocol. Each packet carries a header that uniquely identifies it as data intended for ONU-1, ONU-2 or ONU-3.At the splitter the traffic is divided into three separate signals, each carrying all of the ONU specific packets. When the data reaches the ONU, it accepts the packets that are intended for it and discards the packets that are intended for other ONUs. For example, ONU-1 receives packets 1, 2 and 3; however only two packets are delivered to end user 1

32.4. Upstream Traffic flow in an EPON

32.4.1. The upstream traffic is managed utilizing TDM technology, in which transmission time slots are dedicated to ONUs. The time slots are synchronized so that upstream packets from the ONUs do not interfere with each other one the data is couple onto the common fiber. For example, ONU-1 transmits packet 1 in the first time slot, ONU-2 transmits packet 2 in the second non-overlapping time slot , and ONU-3 transmits packet 3 in a third non-overlapping time slot. Consider the downstream traffic in EPON.

32.5. Benefits of EPON

32.5.1. Higher bandwidth : up to 1.25 Gbps symmetric Ethernet bandwidth More subscribers per PON More bandwidth per subscriber Higher split counts Video capabilities Better QoS

32.5.2. Lower Costs: lower up-front capital equipment and ongoing operational costs Cost reduction in the case of EPONs are achieved by simpler architecture, more efficient operations, and lower maintenance needs of an optical IP Ethernet network Eliminate complex and expensive ATM and SONET elements and dramatically simplify the network architecture Long-lived passive optical components reduce outside plant maintenance Standard Ethernet interfaces eliminate the need for additional DSL or cable modems No electronics in outside plant reduces need for costly powering and right-of-way space

32.5.3. More revenue : broad range of flexible service offerings means higher revenues EPONs support for legacy TDM , ATM and SONET services. Delivery of new Gigabit Ethernet, fast Ethernet, IP multicast and dedicated wavelength services Provisioning of bandwidth in scalable 64 Kbps increments up to 1 Gbps. Tailoring of services to customer needs with guaranteed SLAs (Service License Agreement) Quick response to customer needs with flexible provisioning and rapid service reconfiguration.

33. CWDM

33.1. Transmission using 18 channels (1270 - 1610 nm)


33.2.1. supports up to 18 wavelength channels

33.2.2. wavelength chosen from 1270 nm to 1610 nm

33.2.3. channel spacing 20 nm apart

33.2.4. cost-efficient solution for shorter distances of up to 70 kilometers.


33.3.1. high optical fiber transmission capacity

33.3.2. small volume, low power consumption

33.3.3. good flexibility and expansibility

33.3.4. improve business quality


33.4.1. Less channel count

33.4.2. large channel spacing

33.4.3. low bandwidth compared to DWDM

34. Power Line Communication[ PLC ]

34.1. Definition

34.1.1. Uses electrical wiring to simultaneously carry both data and electric power

34.1.2. Usage of the power grid for control, maintenance and charging purposes by the utility commodities

34.1.3. Systems operate by impressing a modulated carrier signal on power wires

34.2. Important of PLC

34.2.1. Liberalization of telecommunication

34.2.2. New dimensions to the potential application of the electricity infrastructure

34.2.3. Growth of the internet has accelerated the demand for digital telecommunications services to almost every premises

34.3. Issues of the system

34.3.1. Impedance, considerable noise, and high attenuation

34.3.2. Electromagnetic Compatibility (EMC)

34.3.3. Transmission of data rate at Low Voltage to many subscribers also reduces the performances of data rate

34.4. Advantages

34.4.1. Allows consumers to use their already existing electrical wiring systems to connect home appliances to each other and to the Internet

34.4.2. Equalization is perfect High-resolution digital filtering gives very flat filter response as desired

34.4.3. Processing is accurate and reliable

34.5. Disadvantages

34.5.1. Improper performance especially in long distances and in high noise environment

34.5.2. High costs of residential appliances

34.5.3. Lack of global standards