Communications and computer Networking

Agenda

• By the end of this lecture you should be able to: • Define communication • Explain information-communication model • Describe different types of Information and

Communication Technologies (ICT) • Describe key concepts in ICT • Discuss services available on Internet and

WWW and their use in Healthcare

Electronic Communication

• Electronic communication: electronic transfer of information from one location to another.

• Quality of communication between healthcare providers strongly influence the quality of care

• –Traditional: telephone, paper mail, radio, TV • –New possibilities: Fax, e-mail, electronic data

interchange, internet, satellite

Levels of Communication

• Technical level Do the system hardware & software function effectively and efficiently?

• Semantic level Do the message convey meaning? Does the receiver understands the message?

• Effectiveness level Does the message produce the intended result at the receiver? (Hersh, 1996)

Types of Communication

• Synchronous (real time) • Telephone consultation • Interactive tele-video-

conferencing • Telemetry (portable

medical devices) • Internet audio and video

services (telehealth) • Chat rooms (near online)

• Asynchronous – pg.238• fax , postal mail• E-mail • USENET – newsgroups • Listservs • Telemedicine (radiology,

dermatology) • Distance learning

(learning materials)

Types of communication – pg. 236

• Analog • Continuous transmission of

information (e.g., audio and visual frequencies)

• Analog data is more accurate due to continuity

• But analog systems are error prone, because the electronic frequencies get mixed together with unwanted signals, noise, that are nearby.

• Digital • Estimates analog data by

using ones and zeros • Transmission of information

is broken in pieces – “packet-switch’

• Digital data can be manipulated and stored. Noise can be filtered.

• Computers can handle digital data (i.e. “1” and “0”)

Standards-Pg. 235

• Open Standards • Blueprints on how a system

works is public information • Anyone can use publicly

available standards to write software

• Ensure portability of data in case soft/hardware become obsolete

• Example: eMail applications; Linux operating software

• Closed Standards – Are intellectual property – Not publically accessible – Example; Microsoft

• De facto – Standard Unofficial but

popular standard in industry if open or close standards are unrecognized by an established body leading standards

COMMUNICATION TECHNOLOGIES IN HEALTHCARE

Buzzwords

• Bits and Bytes – pg.246• Data Packets• Protocols• Router, Bridge and Gateway• Bandwidth• LAN and WAN• OSI Model• IP Address – we will discuss this in the later slides

Wired Media

• Copper wire• Coaxial cable• Fibreoptic Cable

Evolution of the Internet

• 1958 - 1968 – USA funded DARPA -> became Advanced Research

Project Agency – ARPAnet Established electronic communication channel by packet-switching network – (today INTERNET largest)

– Established rules

1970s and evolution of the internet

• Wide use and adoption of Transmission Control Protocol (TCP) & Inter-net Protocol (IP) – pg.248– TCP/IP provide rules for transmission of data in a reliable, in-order

and end-to-end manner. Every Internet host (e.g. computer, printer) must’ve an IP address

– IP address is in four sets of numbers (e.g. 777.33.55.333) - pg. 249– Issued by IANA in blocks to organizations which administer networks – Organizations are using domains these days (.edu,.org,.com) which

are resolved by web browsers into IP addresses to make connections

• Uptake of TCP/IP rules has led to today’s Internet with global connectivity.

• Graphical User Interface (GUI)

Domain Name System (DNS)

• A Domain Name Service resolves queries for these names into IP addresses for the purpose of locating computer services and devices worldwide.

• 130.63.236.137• Ping

ICANN

• To reach another person on the Internet you have to type an address into your computer -- a name or a number.

• That address must be unique so computers know where to find each other.

• ICANN coordinates these unique identifiers across the world. Without that coordination, we wouldn't have one global Internet.

Further Developments• 1973 • first medically research computer connected • 1980s • developments in other parts of the world;

– policy: commercial organization allowed to join the network – 1989 CERN - Hypertext, hyperlink WWW

• 1990s • –explosive growth of internet •~45 million domains in 1999

and 15,000 healthcare sites • •~50 million consumers searching for health content • Internet is a Network of networks connecting computers and

other devices

Essence of the Internet

Internet is a network of networks connecting computers and other devices

•At the core is Network Connection, typically made of many miles of wires and open communication standards

•Throughput i.e. rate of data transmission b/w two device on network is important to understand.

–Wireless technologies are freeing the reliance on physical medium – Network cards

–Is computer connected to LAN (low cost, fast rate but ↓distance) or WAN (high cost, slow rate but ↑ distance coverage)?

–What is the congestion on network provided by ISP? –What optimizing technology can be used?

Connecting to the Internet

• In other words… –Hardware: Modem (phone line or cable) – Network card • Sharing the communication channel Multiplexing the signal

• packet (frame or datagram ) switching • = block of data used for transmission in packet switched

systems.

• Software • Internet service provider (ISP)

FTP

• Sharing files: Ex: patient history and physical examination, a radiological image

• FTP must be available on both computers • Must know the IP (234.67.345.01) • Access with user ID and password • Type of transfer: binary, ASCII

Usenet or user network Existed BeforeThe web became popular

Bandwidth

• the amount of data that can be carried from one point to another in a given time period (usually a second).

• Increasing bandwidth is being deployed with asymmetric ‘last mile’ technologies suited to entertainment distribution but poorly suited for real-time health applications, that require symmetric upstream and downstream links

• Depends on: transmission medium (e.g., fiber optics, coaxial cable, telephone wire, radio waves)

• the network topology - bus, star or ring• the switching or routing devices used to guide traffic

through the network

Intranet

• Internal internet• Private networks using Internet protocols and technologies

to facilitate collaborative data sharing with security • Ex: Send an email with a document attached to all the

people in organization vs. post the document on the web and provide only the link. – Advantages: Familiar to users, easy to use – Rapid retrieval of information, which may save lives – Improve interdepartmental communication - networking

through the web – Data presentation

Intranet story

• http://blogs.intranetconnections.com/customer_stories/healthcare-wins-with-intranet-mobility

• York Central Intranet

OSI model

• 7 layer model that tells us what different steps need to be fullfilled if two computers are to communicate with each other in a network

Protocols

• Describe how the data will be exchanged between participating computers

• Router, Bridge and Gateway-What is the difference?

• TCP/IP • IP address- we already talked about it

POTS

• Voice-grade service that remains the basic form of residential and small business around the world

VOIP

• Voice over IP • Skype

Client-server

• Overwhelmingly the most popular computing model

• Pg.251• request for service and get it• Fat-client• Thin-client helped by Java• Scalability

OSI Model• The application layer selects a protocol, then passes

the data to the presentation layer, and so on. • Your data works down through the rest of the OSI

layers until it ends up on Layer 1, whereupon it travels over some medium as electronic bits of data.

• Eventually, the receiving network gets your message and processes it in the reverse order, starting from the physical layer and working the data back up to the application layer.

OSI Model -

• Layer 1: physical layer • Layer 2: Datalink • Layer 3:Network• Layer 4:Transport layer

Layer 5: Session • Layer 6:Presentation • Layer 7:Application

Changing Trend

• Enterprise Computing – pg.258• Portal -

Databases

• Pg.258• Part of any proper c/s setup• PC based – Access 2010• Enterprise based – Oracle 9i• Business rules - entity• Tables

Summary

• Communication• Analog, Digital• Bridge, Router and gateway• Bandwidth• Connectors, media• Cloud computing• Bridge, Router and Gateway

Summary

• Development of the Internet• IP address• DNS• C/S• Thin client• Thick client