Last Mile Access Technologies
SCS 3004 – Networking Technologies
Overview
Definition
Examples and their definition
Limitations of last mile
Effective last mile technology
Definition
Last mile technology is the final connectivity leg between the
telecommunication service provider and an individual
customer.
Definition
“The last mile, in the context of telecommunications, refers to the technology providing connection services to and from the user’s office or house.”
Techopedia
“A phrase used in the telecommunications and technology industries to describe the technologies and processes used to connect the end customer to a communications network.”
Investopedia
Today, last-mile technologies include:
• Plain old telephone systems (POTS)
• ISDN, a somewhat faster technology than regular phone service
• Digital Subscriber Line (DSL) over existing telephone twisted pair lines
• Cable and the cable modem for data, using the same installed coaxial cable that
already is used for television
• Wireless, including satellite services such as DirectTV
• Optical fiber and its transmission technologies
• LAN
• Intermediate system
Plain Old Telephone Systems (POTS)
Is defined as the telephone system in which all the communication takes place in analogue form.
Due to its reliability, POTS is used more widely than any other telephony system.
ISDN
• Stands for Integrated Services for Digital Network
• Is a circuit-switched telephone network system
• Also provides access to packet switched networks
• Designed to allow digital transmission of voice and data
ISDN
Digital Subscriber Line (DSL)
• Medium for transferring data over regular phone lines
• Also Known As: ADSL, SDSL
• Speed ranges from 128Kbps to 24000 Kbps
• Advantages of DSL:
• Doesn't require new wiring; it can use the phone line you already have.
• Speed is much higher
Cable Modem
• Is a device that enables you to hook up your PC to a local cable TV line and receive data at about 1.5 Mbps.
• Can be integrated with a set-top box that provides your TV set with channels for Internet access
• .All cable modems can receive from and send signals only to the CMTS
Wireless
• Permit services, such as long-range communications
• Wireless delivery systems
• Light waves and free-space optics
• Radio waves
• Satellite communications
• Broadcast versus point-to-point
Optical Fiber
• A technology that uses glass (or plastic) threads (fibers) to transmit data.
• Fiber optics has several advantages
• Fiber optic cables have a much greater bandwidth
• Fiber optic cables are less susceptible
• Fiber optic cables are much thinner and lighter
• Data can be transmitted digitally
Local Area Network - LAN
• Is a computer network that spans a relatively small area.
• LANs are capable of transmitting data at very fast rates
• Most LANs connect workstations and personal computers.
Intermediate System
• A new type of information transport midway between wired and wireless systems
• Also known as E-Line
Features of effective last mile delivery systems
• Deliver signal power
• Experience low loss
• Support wide transmission bandwidth.
• Deliver high signal-to-noise ratio (SNR) — low unwanted-signal
(Noise) power, N.
• High availability and reliability.
• Low latency; latency must be small compared with required
interaction times.
Challenges of Last Mile Technologies?
• Cost of providing high-tech, high speed services
• Cost of providing high bandwidth services
• Cost of providing services to every single subscriber
• High cost of using fiber optic cables or wires
• Maintenance expenses
Solutions
• Fixed Wireless Access, where a wireless network is used instead of wires to connect a stationary terminal to the wire line network.
• Alternative to the last mile of standard incumbent local exchange carriers:
• WiMAX
• Broadband over power lines
References
1. Investopedia : http://www.investopedia.com/terms/l/lastmile.asp
2. Wikipedia : http://en.wikipedia.org/wiki/Last_mile#Intermediate_system
3. Webopedia : http://www.webopedia.com/TERM/L/local_area_network_LAN.html