Data Communications and Networks - SourceForge

1 data Communications and NetworksAbdul-Rahman ++, VB, ASPA bout the instructor Roles / SkillsROLES# Y PVT LTDC onsultant/HeadCryptoDiv of Defense , RikSof, SecureBytes, RT Japan, Pyntail, SSSProjManager,TeamLead, HeadOffice(ITGroup)ProjCoord/ (GlobalPartner-WSII nternational,Canada.)QMR/Proj/ (AUSbasedsoftwarehouse)ITManager(Compute rEngineer) Nagoya, (AUKbasedsoftwarehouse)TECHNICAL SKILLSDETAILSL anguages & ToolsC++,C#,ObjectiveC,PHP,ASP,VC,VB,COM ,MTS,ATL,HTML,JScript,QtMobile App Development , ,MSSilverlight4,ExpressionBlendProject Management Dotproject,MSProject,Mindmanager6pro, Architecture Rational rose, Design for databases, Erwin modeler, MS Visio 2003 Quality Assurance Testog, PVCS tracker, Requisite pro, Mantus BTConfiguration & Content , CVS, VSS, Git, SharePoint, Mambo Server, Wordpress, DurpalDatabases / RDBMSM ysql, Postgres, Oracle, MSSQL, MS Access, SQLiteServer AdministrationWin server, SUSE Linux, Apache / IIS, postfix, openxpki, samba, privoxyReporting Tools Crystal Reports , Microsoft SQL server reporting / WORKSHOPSCERTIFICATIONSYEARINSTITUTIONDE TAILSQMR certification2005 Softech worldwide (USA)

2 Quality Management Auditing2005 Pakistan Institute of Quality ControlISO 9001:200 Brainbench CertificationsMS Visual C++, ASP, MS Visual Basic2001 BrainbenchCorporation, 14425 Penrose Place, Suite 150, Chantilly, VA 20151, Transcript ID: 2574319VB Transcript ID: 2574319 ASP Transcript ID: 2574319 Microsoft Certified System Engineer1999 Microsoft Certified System Engineer, training at SSUETN etwork Admin, IIS , Tech. Support, Internetworking, Microsoft Certified Professional1998 Microsoft Corporation, Redmond, WA 98052-6399, Win ServerMCP ID: 1270382 AutoCAD certification1993 Computer Guide Institute Release 10 WORKSHOPSYEARINSTITUTIONDETAILSP erformance & Load Testing2009 NUST SEECS, IslamabadSchool of Electrical Engineering & Computer Science, NUST,17-1-2009 network Security2008 Networkers Society of PakSheraton Hotel, Karachi, PDC2007 Microsoft PakistanSQL server 2008 AWARD / RECOGNITIONTRAININGSAWARD/RECOGNITIONYEA RINSTITUTIONDETAILSURLR evised Embedded OS in Operating Systems book by Dr.

3 William2011 Prentice Hall USAISBN-10: 013230998 XISBN-13: 9780132309981 Acknowledged by Dr. William Stallings in book preface (7thEdition).(Embedded OS : TinyOS & ECOS)AlphaPeeler -packaged with Cryptography & network Security book2010 Prentice Hall USAD eveloped at SSUET, Karachi PakistanAuthor of book Dr. William Stallings included this educational tool in his book of cryptography Excellence Award2007 National Bank of PakistanAwarded on meritorious for Professional Engineer2000 Pakistan Engineering # COMP/1343 SOFTEC 98 Award1998 FAST ICS, LahoreImplementation of DesignoCADPROCOM 98 Award1998 FAST ICS, KarachiImplementation of DesignoCADA lphaPeeler Classical cryptography tool1998-2011 Developed at SSUET -Karachi Most popular educational crypto , Linux2010 Ministry of Defense-IslamabadDelivered training for employeesDecision Making, 360 Employee Evaluations2008 The Shams Group (Shams Software Services) internal training: Decision Making, 360 Elicitation, RN, Coding Standards2006 Plexus PVT.

4 LTD. -KarachiSDLC, Development standards & secure coding techniques & tipsPHP, Linux, MySQL2005 Softech Worldwide LLC -USAopen-source technology trainingsData Communications and NetworksChapter 1 IntroductionDefinitions The scope of this course is broad, covering three general areas: datacommunications, networking, and protocols; data Communications deals with the transmission of signals in a reliable and efficient manner. Networking deals with the technology and architecture of the Communications Networks used to interconnect communicating This field is generally divided into the topics of local area Networks : (LANs) and (WANs). 1970s -1980s : merger of the fields of computer science and data Communications : There is no fundamental difference between data processing (computers) and data Communications (transmission and switching equipment). There are no fundamental differences among data , voice, and video Communications The distinction among single-processor computer, multiprocessor computer, local network , metropolitan network , and long-haul network has blurredTrends Traffic growth, development of new services, and advances in technology.

5 Service vs throughput rates:A Communications Model Source generates data to be transmitted Transmitter Converts data into transmittable signals Transmission System Carries data Receiver Converts received signal into data Destination Takes incoming dataSimplified Communications Model -DiagramKey Communications Tasks Transmission System Utilization (Congestion control) Interfacing (device with comm. sys) Signal Generation (form, intensity, interpretable at the receiver) Synchronization (b/t receiver and transmitter) Exchange Management Error detection and correction Flow control Addressing and routing Recovery Message formatting Security network ManagementSimplified data Communications ModelNetworking Point to point communication not usually practical Devices are too far apart Large set of devices would need impractical number of connections Solution is a Communications networkSimplified network ModelWide Area Networks Large geographical area Crossing public rights of way Rely in part on common carrier circuits Alternative technologies Circuit switching Packet switching Frame relay Asynchronous Transfer Mode (ATM)

6 Circuit Switching Dedicated Communications path established for the duration of the conversation telephone networkPacket Switching data sent out of sequence Small chunks (packets) of data at a time Packets passed from node to node between source and destination Used for terminal to computer and computer to computer communicationsFrame Relay Packet switching systems have large overheads to compensate for errors Modern systems are more reliable Errors can be caught in end system Most overhead for error control is stripped out Frame Relayis a standardizedwide area networktechnology that specifies the physical and logical link layers of digital telecommunications channels using apacket switchingmethodology. Uses variable length packets called framesAsynchronous Transfer Mode ATM : sometimes referred to as cell relay, is a culmination of developments in circuit switching and packet switching. Evolution of frame relay Little overhead for error control frame relay uses variable-length packets, called frames, and ATM uses fixed-length packets, called cells.

7 Range of 10s and 100s of Mbps, and in the Gbps range. Constant data rate using packet switching technique. ATM can also be viewed as an evolution from circuit circuit switching, only fixed- data -rate circuits are available to the end Services Digital network Integrated Services Digital network (ISDN) is a set of Communications standards for simultaneous digital transmission of voice, video, data , and other network . Designed to replace public telecom system Wide variety of services Entirely digital domainLocal Area Networks Smaller scope Building or small campus Usually owned by same organization as attached devices data rates much higher Usually broadcast systems Now some switched systems and ATM are being introducedTHE INTERNET ARPANET, which was developed in 1969 by the Advanced Research Projects Agency (ARPA) of the Department of Defense. It was the first operational packet-switching network .

8 ARPANET began operations in four locations. Today the number of hosts is in the hundreds of millions, the number of users in the billions, and the number of countries participating nearing 200. TCP : Vint Cerf and Bob Kahn -May of 1974 TCP/IP protocol suite. This provided the foundation for the Elements of the InternetKey Elements of the Internet The purpose of the Internet, of course, is to interconnect end systems, called hosts; network , routers, WAN, LAN, IP datagrams or IP packets, IP address. LANs are connected to an Internet service provider (ISP) through a point of presence (POP). The connection is made in a series of steps starting with the customer premises equipment (CPE). The CPE is the Communications equipment located onsite with the host. For home users, the CPE is a 56-kbps modem, DSL, cable modem, and satellitePROTOCOL ARCHITECTURE,TCP/IP,AND INTERNET-BASED APPLICATIONSTo destroy communication completely, there must be no rules in common between transmitter and receiver neither of alphabet nor of syntax.

9 On Human communication , Colin CherryProtocol architecture A protocol architecture is the layered structure of hardware and software that supports the exchange of data between systems and supports distributed applications, such as electronic mail and file transfer The most widely used protocol architecture is the TCP/IP protocol suite, which consists of the following layers: physical, network access, internet, transport, and application. Another important protocol architecture is the seven-layer OSI model. (Open Systems Interconnection)Protocols Used for Communications between entities in a system Must speak the same language Entities User applications e-mail facilities terminals Systems Computer Terminal Remote sensorKey Elements of a Protocol communication is achieved by having the corresponding, or peer, layers in two systems. The peer layers communicate by means of formatted blocks of data that obey a set of rules known as a protocol.

10 The key features of a protocol are as follows: Syntax data formats Signal levels Semantics Control information Error handling Timing Speed matching SequencingProtocol Architecture Task of communication broken up into modules For example file transfer could use three modules File transfer application communication service module network access moduleSimplified File Transfer ArchitectureA Three Layer Model network Access Layer Transport Layer Application LayerNetwork Access Layer Exchange of data between the computer and the network Sending computer provides address of destination May invoke levels of service Dependent on type of network used (LAN, packet switched etc.)Transport Layer Reliable data exchange Independent of network being used Independent of applicationApplication Layer Support for different user applications e-mail, file transferAddressing Requirements Two levels of addressing required Each computer needs unique network address Each application on a (multi-tasking) computer needs a unique address within the computer The service access point or SAPP rotocol data Units (PDU)