hafta Brazzers studyolarinda calisip emek sarfeden koca memeli Phoenix Marie izin porno indir gununde de kocasina vermeye karar veriyor Kocasinin da Brazzers icin calistigini unutmus porno video sayilir Kendi yatak odasinda oyle profesyonel bir seks yapiyor ki cekici hatun yine redtube harikalar yaratmis seksi guzel hatun sert erkeklerden ve koca penislerden cok hoslaniyor porno video guzel zenci hatun bu seferde genc bir erkek ile geldigi evde muhabbetin dibine porno vuruyor Zenci kari seksiligi ile adami kendinden ediyor resmen adam kari karsisinda daha fazla dayanamiyor
Log in

Login to your account

Username
Password *
Remember Me
India's Leading Source for Broadcasting & Broadband Information - CableQuest Magazine
HomeArticlesTechnicalLast-mile technologies
Wednesday, 04 March 2015 07:24

Last-mile technologies

email this page

Last-Mile technology is any telecommunications technology that carries signals from the broad telecommunication backbone along the relatively short distance (hence, the "last mile") to and from the home or business. Currently there are predominantly two types of service networks to the residence of users – TV and Telephone. TV services are provided through direct to home (DTH) satellites or cable TV or IPTV networks, whereas telephone services are provided through POTS, ISDN, Wireless in local loop (WiLL) and mobile networks.

Last-Mile technology represents a major remaining challenge because of the fact that the cost of providing high-speed, high-bandwidth services to individual subscribers in remote areas can be higher than the service provider would like. Laying wire and fiber optic cables is an expensive undertaking that can be environmentally demanding and require high maintenance. Category of Last-Mile Technologies

Today, last-mile technologies may be categorised into:

One of the major considerations in providing the last mile would be the link bandwidth required for the various services available to the user. Link banwidth can be categorised into average continuous bandwidth required per user and maximum burst rate per user. The estimated download times of a full length DVD movie (7 GB) using various network connection speeds is given as below :-


Any futuristic access technology should provide the capability to download a multi-gigabyte file within a few minutes into the end equipment. The bit rates of different prevalent TV signal transmission technologies in India are : 

  • DVB-C rates vary from 6 to 64Mbps for MPEG-2 whereas 

  • DVB-C2 allows bitrates up to 110.8 Mbps. 

  • DVB-T bitrates fall in the range of 5 to 32 Mbps and 

  • DVB-T2 supports 7 to 50 Mbps.

Also, high QoS with real-time presentation of high definition television (HDTV) requires a continuous average rate of at least ~20 Mbps. The future where we envisage the convergence of voice, video, data, TV etc., would require average bandwidth in the range of 100 Mbps and burst rates in the range of 1 Gbps per user. Aggregation within the network requires that even higher single channel rates exist within the access networks and these would be in the range of 10 Gbps. In addition, the technologies that would be able to sustain these rates as part of the natural growth of systems already installed or planned would be winners.  The basic challenges in media streaming that must be considered, include “unknown” and “variable bandwidth”, “delay jitter” and “losses”. How the various last mile technologies deal with these challenges, ultimately leads to the best solution for the end user, in terms of performance.

Apart from the bandwidths available, we should also see the cost of providing that bandwidth per user and the willingness of users to pay for that bandwidth. Access technologies have different cost/performance trade-offs compared to backbone networks. Low cost, high bandwidth and high QoS are major requirements because the end user has to bear this cost and in many cases, it is not shared among end users. We have evaluated the last mile technologies listed above, for their suitability w.r.t providing converged services (voice, data, video, TV) in the table given below :


1. xDSL on Plain old telephone system (POTS)/Type:
Wired (twisted pair phone lines)

Advantages: Symmetric digital subscriber line (SDSL) - up to 1,544 kbit/s (1.5Mbit/s) Asymmetric digital subscriber line ADSL2 - up to 12 Mbit/s and 3.5 Mbit/s ADSL2+- up to 24 Mbit/s and 3.5 Mbit/s Very-high-bit-rate digital subscriber line (VDSL)-  up to 52 Mbit/s and 16 Mbit/s VDSL2 - sum of both directions up to 200 Mbit/s. G.fast- approx 1 Gbit/s aggregate uplink and downlink at 100m. Provides voice, video, SMS, FAX and data. Reasonable cost. Reach upto3 km. immediately available using existing infrastructure. Fiber optic technologies exist today that allow the conversion of copper based ISDN, ADSL and DSL over fiber optics.

Disadvantages: Limited bandwidth. Distance is big limitation of DSL. Data rates are distance sensitive. It has road digging and maintenance issues. Even in Delhi, service providers take more than a week to restore the line and during that time, the line is dysfunctional.

Suitability: It may be possible to give converged services through IPTV, VoIP and data. Rates available are per user therefore bandwidth would be constant. Losses would increase with distance but are lesser than wireless. Maintenance is an issue.


2. ISDN/Type:
Twisted-pair PRI: T-1 or E1 line

Advantages: Voice, FAX and data

BRI: 64 Kbps to 128 Kbps

PRI: 23 (T-1) or 30 (E1) assignable 64-Kbps channels plus control channel; up to 1.544 Mbps (T-1) or 2.048 (E1)

Suitability: Rates are not sufficient for converged services.


3. Cable broadband/Type:
Wired (co-axial cable

Advantages: Downstream 250 Mbps for residential services. Upstream 384 kbps to 20 Mbps. Shared downstream connections, so bandwidth depends on number of simultaneously active users. Reach 160 km. Can support entertainment, data, voice, Packet. Cable networks use the Internet Protocol (IP) to enable a wide range of multimedia services, such as Voice over IP (IP telephony), multimedia conferencing, interactive gaming, and general multimedia applications over the same lines used for TV and Internet access.

Disadvantages: At present one way and badly laid out. Totally new infrastructure may be required. Calls to be carried over a managed IP network guaranteeing QoS.

Suitability: Converged services are possible but with new/updated infrastructure. Shared connection, so bandwidth per users variable as it depends on number of simultaneously active users. Losses are less as compared to DSL and wireless. 


4. Radio Frequency over Glass (RFoG)/Type:
Wired, Hybrid Fibre Co-ax (HFC) Network

Advantages: Coaxial portion of the hybrid fiber coax (HFC) network is replaced by a single-fiber passive optical network (PON). Downstream and upstream spectrum increases and noise decreases. Existing Cable Network elements are reused. Disadvantages: Network and CPE devices would also need upgradation.


5. GSM & HSCSD (2G & 2.5 G) High Speed Circuit Switched Data

Type: Wireless Supports Voice over IP, SMS and data traffic of 56 to 114 kbps General Packet Radio Service GPRS (2.5G)

Suitability: Rates are not sufficient for converged services. Rates are not sufficient for converged services.


6. Enhanced Data rates for GSM Evolution EDGE (2.5G)

Advantages: Supports voice, SMS and data rates upto 384 kbps

Suitability: Rates are not sufficient for converged services. 


7. 3G

Type: Wireless 2100 MHz

Advantages: >21Mbps Downstream and 5 Mbps upstream. Reach 200 km. In low demand and low ARPU’s. Voice, data, video, mobility. TV proposed via MBMS. IPTV is available on IMS.

Disadvantages: Allocated spectrum is way too less for most of broadband needs and can’t provide good broadband speeds in big cities. Needs investment in upgrading equipment on existing towers.

Suitability: 3G is suitable for converged services in low demand areas or small cells. Losses increase in certain bad weather conditions. Radio signal quality and reliability is an issue, but can be sorted out.


8.  Long Term Evolution LTE 4G/Type:
Wireless

Advantage: 100 Mbps Downstream and 50 Mbps upstream. Reach 200 km. Mobility, Voice, data, video. TV proposed via eMBMS.

Disadvantages: Costly spectrum. New technology. Infrastructure cost.

Suitability: It is suitable for converged services as it provides mobility in addition but infrastructure cost may be high. Losses and delay jitter may be more as compared to wired connections.


9. LTE-A

Advantage: Theoretical data download rates 3GBpsand upload rates1.5 Gb/s. LTE-A also includes new transmission protocols and multiple-antenna schemes that enable smoother handoffs between cells, increase throughput at cell edges, higher network capacity, more consistent connections, and cheaper data.

Suitability: It is suitable for converged services as it provides mobility in addition but infrastructure cost may be high. Losses and delay jitter may be more as compared to wired connections.


10. WiMax/Type:
Wireless over 802.16e-2005

Advantage: Licensed spectrum. 40 Mbps Downstream. 17 Mbps upstream. 6.4 km reach. Providing mobility, data, telecommunications (VoIP) and IPTV services (triple play). Addresses security and QoS requirements.

Disadvantage: limited and costly spectrum. Distance limits the speed. Globally WiMax seems failing against it’s competitor LTE. Suitability: It is suitable for converged services as it also provides mobility. New infrastructure deployment may again be costly. Deployments are not many and LTE would be more popular.


11. WiFi/Type:
Wireless over 2.4 GHz on 802.11n.

Advantage: 600 Mbps. Reach 50 m. shared wireless internet access. Point to multipoint.

Disadvantage: Open spectrum makes it terribly prone to interference, apart from limited bandwidth of 22MHz. Shared connection makes data contention and collisions frequent. To cover big area, wifi needs lots of Access Points & to serve them itself is a challenge.

Suitability: Theoretically it may be a strong contender for providing converged services through IPTV, VoIP and data access, but losses due to interference, delay jitter and shared variable bandwidth make it practically unviable.


12. GPON/Type:
Optical Fiber

Advantage: 2.5 Gbps large bandwidth.  60 km reach. Split ratio (1:32). Extremely scalable. Convenient support of IP and Ethernet. More reliable. Easy upgradeability, ability to support fully symmetric services, long transport distances and inherent immunity to electromagnetic interference.

Disadvantage: The primary drawback is the cost associated with electrical to optical conversion. Needs completely new infrastructure. Deployment and maintenance cost makes it expensive.

Suitability: Already a popular option in the backbone networks, it is a very strong contender for future access networks to provide converged services due to high bandwidth and low loss rate. Infrastructure cost (installation and maintenance) and lack of mobility may be a deterrent.


13. Ethernet in the First Mile (EFM)

Advantage: Copper - Full-duplex short reach Point-to-Point link over voice-grade copper wiring.minimum of 10 Mbit/s up to 750 m.

Active Fibre Optics – provides point to point 100-1000 Mbps upto at least 10 km

Passive Fibre Optics - provides point to multipoint 1000 Mbit/s Ethernet links over PONs, upto at least 20 km, at the split of at least 1:16 to 1:64.

Disadvantage: substantially high. On-standard service-level interoperability


14. Broadband over Power Line/Type:
Power line

Advantage: Broadband over power line (BPL) is a technology that allows data to be transmitted over utility power lines. It can carry data and voice.

Disadvantage: Data rate of few Mbps

Suitability: Even if BPL is not accepted as a viable way to deliver converged services, it may find a place in helping consumers to manage their energy consumption. High-speed data transmission between electrical plugs in a building would allow devices such as thermostats, appliances and smart meters to communicate with each other.


15. Satellite (DTH)/Type:
Wireless

Advantage: Satellite –Ka band (Not Ku-band)– is suited for high speed Internet Access, B-ISDN, voice, TV and Mobility. Reach 100-6000Km.

Disadvantage: Downstream 1 Mbps, upstream 256kbps. Latency. Technology still in trail stage. Futuristic.

Suitability: It can provide converged services, the only issue would be latency. Losses increase in certain bad weather conditions.


16. E –band/Type:
Fixed Wireless Advantage: Licensed band (70 – 80 GHz), it is suitable for high speed, point to point, line of sight links for data access. Full duplex data rates of 1Gbps or more. Constant data rate in all weather conditions. Quickly deployable and low cost. High power, high antenna gain, low level modulation schemes. Interference protected. Cost effective in comparison to fibre.

Disadvantage: Suitable for line of sight applications. Reach is less 1.6 km. Phase noise can impact bandwidth efficiency. Due to operation in very high carrier frequency, power output levels are low.

Suitability: Suitable for converged services in a smaller area or touch terrain.

Conclusion: Broadband wireless networks will eventually be required to provide the solution and meet everyone's needs. The US Cable Industry is the main deliverer of Internet services in USA. In India, the Government has given the roadmap for adopting Digital Set-Top-Box (STB) for the cable TV reception. Transformation of Television (ToT) is taking place with Wi-Fi connectivity and “mobile Apps” interface. Indian TV Cable Industry can become the main delivers of Internet Services.

email this page

Share this post

Submit to DeliciousSubmit to DiggSubmit to FacebookSubmit to Google PlusSubmit to StumbleuponSubmit to TechnoratiSubmit to TwitterSubmit to LinkedIn
Cable Quest Annual Issue 2018
One 2 BHK Flat Available
Wanted - English Journalist, Excel Operator, Web Marketing
ANGA COM
Subscribe to Cable Quest

Calendar

June 2019
S M T W T F S
26 27 28 29 30 31 1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30 1 2 3 4 5 6

Latest News

Magazine Archives Year 2014-2015

  • Cable Quest Magazine Archive - June 2015

    Jun 2015

  • Cable Quest Magazine Archive - May 2015

    May 2015

  • Cable Quest Magazine Archive - April 2015

    Apr 2015

  • Cable Quest Magazine Archive - March 2015

    Mar 2015

  • Cable Quest Magazine Archive - February 2015

    Feb 2015

  • Cable Quest Magazine Archive - January 2015

    Jan 2015

  • Cable Quest Magazine Archive - December 2014

    Dec 2014

  • Cable Quest Magazine Archive - November 2014

    Nov 2014

  • Cable Quest Magazine Archive - October 2014

    Oct 2014

  • Cable Quest Magazine Archive - September 2014

    Sep 2014

  • Cable Quest Magazine Archive - August 2014

    Aug 2014

  • Cable Quest Magazine Archive - July 2014

    Jul 2014

  • Cable Quest Magazine Archive - June 2014

    Jun 2014

  • Cable Quest Magazine Archive - May 2014

    May 2014

  • Cable Quest Magazine Archive - April 2014

    Apr 2014

  • Cable Quest Magazine Archive - March 2014

    Mar 2014

  • Cable Quest Magazine Archive - February 2014

    Feb 2014

  • Cable Quest Magazine Archive - January 2014

    Jan 2014

Do you have a Complaint

World of Spiritual & Divine Thoughts | Shri Guru Nanak Dev Ji

hızlı öfkeli 8 izle canlı maç izle hd film izle film izlecanlı maç izle
X

Right Click

No right click