New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here


by: Chesley Lind


Marketplace > Virginia Commonwealth University > Science > INFO 370 > FUND OF DATA COMMUNICATIONS
Chesley Lind
Virginia Commonwealth University
GPA 3.57


Almost Ready


These notes were just uploaded, and will be ready to view shortly.

Purchase these notes here, or revisit this page.

Either way, we'll remind you when they're ready :)

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Class Notes
25 ?




Popular in Course

Popular in Science

This 8 page Class Notes was uploaded by Chesley Lind on Wednesday October 28, 2015. The Class Notes belongs to INFO 370 at Virginia Commonwealth University taught by Staff in Fall. Since its upload, it has received 28 views. For similar materials see /class/230632/info-370-virginia-commonwealth-university in Science at Virginia Commonwealth University.

Similar to INFO 370 at Virginia Commonwealth University




Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 10/28/15
Networks and Telecommunications Basics Networks any connectivity between two or more computers or devices Telecommunication systems any systems that allow us to exchange data Network Basics LAN Local Area Network MANMetropolitan Area Network WAN Wide Area Network Network typically includes 4 things besides the computers themselves Protocol 3 set of common rules to make sure that everyone speaks the same language Network Interface Card NIC card that plugs into the back or side of your computers and lets them send and receive messages from other computers Cablethe medium that connects all of the computers together Hub Switch or Router hardware perform traffic control Networks are differentiated by the following Architecturepeer to peer clientserver Topology bus star ring hybrid wireless ProtocolsEthernet Transmission Control ProtocolInternet Protocol TCPIP Mediacoaxial twistedpair fiber optic Ch1 Business Data Communications Intro Objectives 0 Understand the basic requirements for data communications Trends Driving Data Communication 0 Traffic Growth 0 Voice and Data local and long distance 0 Development of new services o In turn drives increased traffic 0 Advances in technology 0 Encourage and support increased growth and development Convergences we need our network to still handle things like telephone voice mail ect We study it as Applications want similar interface or usability on every end Enterprise Services and Infrastructure just how you want to hook your shit up Benefits of Convergence Efficiency reduction in operation costs Effectiveness Transformation UC Merges realtime communication services w nonrealtime collaboration and business process applications Nature of Business Info Requirements Voice Communications VoIP PBX and Centrex Data Communications Ch 2 Business Information Business Data Communications 6e 4 shapes of data Voice Images Video Data Analog Data 0 Continuous Signal 0 Expressed as an oscillation sine wave format of frequency 0 Information rate and channel cap Centralized Data Processing working from one server 0 Computers computer s located in central facility 0 Processing all applications are run on the centeral data processing facility 0 Data data are stored in files and databases at the centeral facility 0 Control a data processing or IS manager has quot quot39 for the 39 39 Idata r facility 0 Support A centralized site includes technical support staff to operate and maintain the site What are the advantages 0 Economies of scale equipment and personal 0 Lack of Duplication 0 Ease in enforcing standards security 0 One is technology and the other is the employees themselves Distributed Data Processing 0 Computers are dispersed throughout organization 0 Allows greater flexibility in meeting individual needs 0 More redundancy o More autonomy o Encourages greater sense of ownership 0 Encourages better match of resources to needs Distributed Data Processing DDP 1 3 7 8 9 More companies are selecting DDP becaluse o Dramatically reduced workstation costs 0 Improved user interfaces and desktop power 0 Ability to share data across multiple servers 0 Need for shorter response time DDP provides a better solution than does a centeralized structure ClientServer Architecture 0 Combines advantages of distributed and centeralized computing 0 Costeffective achieves economies of scale 0 Flexible scalable approach Intranets 0 Uses Internetbased standards amp TCPIP Ethernet 0 Contact in accessible only to enterprise users not open to the public A specialized form of clientserver architecture Can be managed unlike Internet Distributed applications 0 Two dimensions characterize the distribution of application processing 0 Allocation ofapplication functions 0 One application split up into components running on a number of machines eg accounting system 0 Vertical Partitioningdistributed in a clinetserver arrangement 0 Ex Retail chain POS where everyone has same client and periodically sales and inventory data is transmitted to servers 0 Horizontal partining distributed amoung number of peer same level computers no clientserver notion I One application performing independently replicated on different systems 0 Ex Office Automation Tools on your screen your working on excel and another you are typing something elseect o Other forms of DDP 0 Distributed devices I Ex ATM machines factory robots 0 Ways to Organizing Database 0 Make it all centerized or make it replicated or portioned database distinct non overlapping segments dispersed amoung multiple computers I Pro no duplication Terms Mean time between Failures MTBF Mean time to repair MTI39R Avalibility MTBF MTBFM 3939R Avalibility Uptime Uptime Downtime Chapter 4 The Internet ARPAnet first packet switching network Switching Method 0 Circuit Switching Requires a dedicated communication path for duration of transmission wastes bandwidth but maintains communication synchronization They have dedicated Line connecting you to that person that line is fully utilized However you can not utilize it for other tasks during your quotidlequot times Message Switching Entire path is not dedicated but entire message is move from hop to hop as a unit resulting in long delays from intermediate storage and repetition of message at each hop The line is only used between you and the first serverrouter connected to you Any failure you will loose the entire message Packet Switching Specialized message switching where message is divided into packets with very little delay Divided documents into frames w some controlling quotoverheadquot bits frames sent via llframe Relaysquot Then they send the packet from the sender to the receiver They use different paths to get there Internet Addressing 32bit global internet address Includes network and host identifiers Dotted decimal notation 11000000 11100100 00010001 00111001 binary 1922281757 decimal We have 5 types of networks A B C D E A biggest businesses B Average Businesses C Home User D Networking Research Cisco Example E Broadcasting Domain Name System 320bit IP address have two drawbacks o Routers can t keep track of every network path 0 Users can t remember dotted decimals easily DNS Components 0 Domain name space I Tree structured name space to identify all internet resource I Look at Figure 45 Portion of Internet Domain Tree 0 DNS Database 0 Hierarchical Database containing resource records RRs These RRs include name IP address other info about hosts 0 Each name server configured for a specific local zone I Includes subdomains and associated resource records RRs 0 DNS Operation 0 Figure 46 DNS Name Resolution Chapter 5 TCPIP and OSI What is a protocol Allows entities application programs from different sys To communicate Shared conversions rules for communicating info Are called protocols Rules include syntax semantics and timing Why use protocol Architecture Data Comm s complex 0 Sender identifies data path to receiver 0 Sys Negotiate preparedness 0 Applications negotiate preparedness 0 Translation of file formats For all tasks to occur a high level of organization and covoperation is required Network Access Layer 0 Concerned w exchange of data between computer and network 0 Includes addressing routing prioritizing ect 0 Different networks require different software at this layer 0 Ex X25 standard for network access procedures on packetswitching networks 0 Old protocol from b4 the osi model 3 layers physical data link and network X25 Operates over Virtual Circuits 1400 Application Layer Logic needed to support various applications Each type of networking Transport Layer Addressing Another View Figure 53 Protocols in a Simplified Articture Data Transmission App layer creads data block Transport layer appends header to cree PDU Standardized Protocol Architectures o Standardized protocols make things more compatible and vendors like them bc they are more marketable o 2 common ones are TCPIP Comparing OS and TCPZIP All People seem to Need Data Processing Upper layers give information to layers below them 1 Application our data is going to be called quotRecordsquot adds Socket NumberPort No a Logic needed to support variety of applications b Separate module supports each type of application ex File transfer 2 Presentation 3 Session 4 TransportHosttoHost a Reliable exchange of data between applications b Uses TCP protocols for transmission 5 Networkresponsible for IP addressingone protocol that we know is the IP a Exchange of data between sys on a shared net b Utilizes address of host and destination c Can also prioritize transmission d Software at this layer depends on networkx25 vs Ethernet e Segregation means that no other software needs to be concerned about net specifics 6 Data 7 Physical Layer a talks about the physical connections between two or more devices b Converting data to bitsbites c Characteristics of the medium Internet Layer 0 An Internet is an interconnection of two or more networks Internet layer handles tasks similar to network access layer but between networks rather than between nodes on a network 0 Uses IP for addressing and routing across networks 0 Implemented in workstations and routers 0n the receiver s side they start from 7 and work their way to 1 TCP 3 way handshakeamp UDB user data protocono real handshake UDP is used widely in broadcasting such as TVRadio ect 0 Most TCPIP apps use TCP for transport layer 0 TCP provides a connection logical association between two entities to regulate flow check errors 0 UDPUser Diagram Protocol does not maintain a connection socalled connections and therefore does not guarantee delivery preserve sequences or protect against duplication Is used in SNMP Simple Network Management Protocol 0 TCP is larger than UDP bc of the extra protocol info IP and IPv6 0 IP provides for 32bit 86 x 10quot9 source and destination address 0 IPv6 1996 standard provides 128bit 68 x 10quot38 0 Migration to IPv6 is SUPER SLOW IP Headers 0 Figure 57 IP Headers TCPIP Applications 0 SMTP simple mail transf protocol 0 FTP o Telnet 0 Remote login capability allowing a user to emulate a terminal on the remote sys Not Secure o SSH Secure Shell 0 Provides a secure remote login capability using photography Replaces Telnet


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Anthony Lee UC Santa Barbara

"I bought an awesome study guide, which helped me get an A in my Math 34B class this quarter!"

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.