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Janak Chandarana (05329R04) Sravana Kumar K (05329034). Study on technologies for communication in rural areas. Guide: Prof. Sridhar Iyer. KReSIT, IIT-Bombay. Problem Definition. One communication line which is shared by large number of people within small range of geographical area.
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Janak Chandarana (05329R04) Sravana Kumar K (05329034) Study on technologies for communication in rural areas Guide: Prof. Sridhar Iyer KReSIT, IIT-Bombay
Problem Definition • One communication line which is shared by large number of people within small range of geographical area. • Communication line can be PSTN telephone line, GSM or CDMA. • We need to use this Single line across whole area for better utilisation of communication.
Problem Definition (cont.) • We need to have intranet, which will goes everywhere in the village. • The Intranet can be wired or wireless. • Once we have the intranet and communication line, then we need to extend this line to entire intranet.
Motivation • Real Life problem • Urgent necessity • Convergence of VoIP, WiFi, PSTN and PBX • Contribution • Feasible and affordable solution • Solution is applicable to many Indian villages • Working solution • People are using it !!
Existing Solution for given problem • Conventional PBX • Expensive • Cables are not so good communication medium for a given problem • Complex • Lot of manual work • GMRS • Can not interface with outside world
Study of various deployment Option • Selection of communication medium to communicate with world • Selection of medium for intranet through which Internal communication can be established • Interfacing communication line with intranet
Available Communication medium • Telephone Line • Advantages • Easy to deploy • Telephone Instruments are cheap and easily available. • Conversion from telephone signal to any other signal is relatively easy than any other medium. • Ease of setup and use • Disadvantages • No mobility for fixed telephone landline. • Re-configuration is really hard once installed
Communication medium (cont) • GSM • Advantages • Mobility within village • Roaming for outside use also. • Easy to deploy (no landline installation) • We can move entire setup for any other village • Disadvantages • power consumption is high (need to recharge batteries.) • Recurring cost of billing is high • Not so easy to convert to any other format (for example GSM to VoIP)
Communication medium (cont) • CDMA • Advantages • Mobility within village • Signal can be transmitted over greater distances, it may give reception in more remote or rural areas where a GSM phone does not pick up a signal • Roaming with soft-handoff • Easy to deploy • Disadvantages • Hard to convert to any other format (for example CDMA to VoIP) • Mobile handset cant be used for GSM providers. • Higher cost
Available option for intranet • Wireless LAN • Advantages: • Deployed without cabling, potentially reducing Installation effort • Supports mobility • WiFi is a global set of standards. Unlike cellular carriers, the same WiFi client works in different countries around the world. • Disadvantages: • Power consumption is fairly high compared to some other standards • Battery life and heat is a concern. • limited range. • Interoperability issues between brands or deviations in the standard can cause limited connection or lower throughput and speeds.
Available option for intranet (cont) • 802.3 based Ethernet • Advantages: • It strikes a good balance between speed, cost and ease of installation. • Wide acceptance in the computer marketplace and the ability to support virtually all popular network protocols. • Almost no packet drop. • Cheap devices and media. • Disadvantages: • Its fixed Installation. Once setup, Its really hard to re-configure. • If wire gets disrupted, we need to replace cable.
Available option for intranet (cont) • corDECT • Advantages • The capital and operational costs for running the corDECT system is low. • The system's components are designed to work in harsh environment • As the power consumption of the corDECT exchange is very low, investments on UPS would also be low. • Disadvantages • It is yet to be commercially introduced in India by the DoT
Available option for Intranet (cont) • GMRS • Advantages; • There is no cell site, no telephone operator and no roaming charges. • Two-way radio communication is practical and fun. • No centralized AP needed. • P-2-P kind of communication. • Disadvantages: • Not compatible with other Networking standard. • Can not interface with computer. • Problems of licensing with government.
Requirements • Our Solution for a given problem has following requirements. • Hardware Requirements: • Access Points • Antennas • Adapters • Gateways • PCI cards • Switches • Ethernet Cables
Requirements (cont.) -VoIP Clients • WiFi VoIP Phones • Laptops • Desktop PCs • Simputers • Software Requirements • Asterisk Server • Softphones • SJ Phone • X-lite Phone
Access Point • Requirements: • 802.11 • Potentially excellent LAN performance, especially with careful configuration and placement • Easy to configure (GUI support) • Should Support external Antenna • Can afford one time higher CAPEX cost • least OPEX cost • Low power consumption
Access Point • Suggested Solution: • Model: The D-Link DWL-2100AP Access Point • Wireless Frequency Range: 2.4GHz to 2.4835GHz • Wireless Signal Range • Indoors: Up to 100 meters • Outdoors: Up to 400 meters • Wireless Transmit Power: 15dBm • Power Input: Ext. Power Supply DC 5V, 2.0A • Dimensions: 142mm X 109mm X 31mm • Weight : 200g • cost: Rs. 7,000
Antenna • Requirements: • Signal Range:- 200 mts or more • Should work in partially Line of sight also • Less CAPEX cost • Minimum OPEX cost • Antennas should give excellent throughput over large areas. • Effect of direction on Signal strength
Antenna • Solution • Model: D-Link ANT24-0801 8.5 dBi Directional Wireless Antenna • Frequency Range: 2300MHz to 2500MHz • Power Handling: 50W • Antenna Range: Up to 150 meter • Dimensions: 120mm X 120 mm X 43mm • Weight: 300g • Cost: Rs. 9,500
VoIP Gateway • Requirements • It should convert analog telephone signal to VoIP • Compatible with asterisk server. • should supports SIP • Telephone line should work even when gateway is switched off. • Should consume less power
VoIP Gateway • Solution • Model: Sipura VoIP Gateway SPA-3000 • One RJ-45 port and One RJ-11 port • Power Consumption: 50 watts • Box dimensions: 183mm X 152mm X 64mm • Weight: 490g • Cost: Rs. 6,500
VoIP-PSTN Adapter • Requirements • It should have at least one RJ-45 pin as well as one RJ-11 pin • It should support multiple telephone instruments • Support for Session Initiation Protocol (SIP) • Lower CAPEX and OPEX cost • Compatible with asterisk server
VoIP-PSTN Adapter • Solution: • Model : LinkSys PAP2-NA 2-Port VoIP Gateway SIP FXS Adapter • One RJ-45 Port , two RJ-11 port • Supports both DHCP and SIP • Power Supply: 5V DC 2.0A • Dimensions: 101mm X 101mm X 15mm • Weight: 140g • Cost: Rs. 4,500
PCI VoIP cards • Requirements • It should converts the analog telephone signal to VoIP • It should have one RJ-11 FXO port (and/or one FXS port) • Easy to configure (Preferably Plug and play feature) • Compatible with Desktop PC’s motherboard • Support Asterisk PBX
PCI VoIP cards • Solution • Model: Digium X100P FXO clone PCI card • Supports Asterisk PBX • One FXO pin and One FXS pin • Cost: Rs. 2600
Client Side Devices • Requirements • Less power consumption • Higher portability • Easy to install • Low price • High Tx-Rx antenna
Client Side Devices • WiFi Phones: • Model: Linksys WIP300 Wireless-G IP Phone • Operates in the 2.4GHz band • Supports 802.11g and the VoIP SIP protocols • High Resolution Color LCD screen • USB Charger Interface • Cost: Rs. 6000
Client Side Devices (cont.) Simputer • Model: Amida 2200 Simputer • It supports SIP • Less Power consumption • Nice VoIP client software . • More Portability • Multi purpose device • can be used in education • Cost: Rs. 15,000
Client Side Devices Soft phones: • should allows voice transmission on LAN • support SIP • Easy to configure • Examples: • SJ Phone • X-Lite Phone
Asterisk soft PBX • Asterisk is open source software PBX • It runs on Linux • It supports SIP • Runs on almost all hardware • All the functionality of conventional PBX • Fast, robust and free!
Case Study • Timbaktu Collectives • Timbaktu Collective is a registered voluntary organization that was initiated in 1990 • Timbaktu is surrounded by hills and is far from any urban area in Andhra Pradesh, India. • They don't have any GSM or CDMA coverage. • Telephone department had provided one telephone line to Timbaktu. • They don't have Electricity supply. • They are using solar power. • Timbaktu has lot of trees in between which may become obstacle for wireless communication.
VoIP based Solution • Phase 1(dec-05): • We had identified 802.11 WiFi as Intranet solution for communication. • We had deployed Asterisk Server over Linux machine and It was connected with Access Point over WiFi. • All other clients like simputer, soft-phones and LinkSys Adapters were communicating with Asterisk. note: Trees which comes in between antenna and client attenuate signals greatly.
VoIP based Solution • Phase 2(feb-06): • We had thought of Ethernet cables as medium for some part of village which are nearer to communication line. • Wireless had very higher rate of packet drop which was bigger constrain for voice communication. • VoIP asterisk server was also connected through access point which provides connectivity to wireless VoIP clients such as simputer. • We had VoIP gateway which can serve incoming/outgoing calls.
VoIP based Solution • Phase-3 (future plan) • Deployment of hybrid solution which use Wireless as well as Ethernet based solution • Stand alone hardware(3 in 1) which has VoIP gateway, asterisk PBX and VoIP adapter in a single box. • Low cost wireless VoIP client (like GMRS) which can work with 802.11
Conclusion • Every time we don’t need best “technical” solution. • But we need affordable, feasible, working and quickly available solution which is easily acceptable. • VoIP has great potential for Indian rural development. • Proposed 3-in-1 box can change telecom market in India largely.