Today’s(Lecture(• This Course – Goals – Outline/Schedule – Grading Policy • Introduction to Multimedia Networking #1(G(Review(of(Networks( 3
2 1.1.2 Data Representation: Information today comes in different forms such as text, numbers, images, audio, and video. Text: In data communications, text is represented as a bit pattern, a sequence of bits (Os or Is)
CS425: Computer Networks Bhaskaran Raman [braman] AT [cse.iitk.ac.in] ... Tutorials & lectures possibly combined with EE673 (Digital Communication Networks)
Notes on Computer Networks v 3. Network layer Climbing up one level above data link layer is the network (or internet) layer. This layer conveys a
MC9231 – COMPUTER NETWORKS 5 CCET PREPARED BY : S.PON SANGEETHA/AP Circuit switching is implemented in Broadband n/w
PART IV in Textbook ... ่า Capacity ข นอยึ้ ู่กับการท ํา Flow Control ... ถอธบายโดย Queuing Theory
The Network Layer in the Internet: The IP Protocol, IP Addresses, Internet Control Protocols, OSPF-The Interior Gateway Routing Protocol, BGP-The Exterior Gateway Routing Protocol, Internet Multicasting, Mobile IP,IPv6. UNIT-III (15 Hours)
COMPUTER NETWORKS AND DATA COMMUNICATION ... Lesson 5 10 Lesson 6 Line Configuration, Topologies 12 ... feedback …
235032 Computer Networks
School of ICT, University of Phayao Dr.Sukchatri PRASOMSUK
Text Books CCNA Certification All-in-One for Dummies, by Silviu Angelescu, Wiley Publishing Inc., 2010 Networking for Dummies, 10th edition, by Doug Lowe, Wiley Publishing Inc., 2013 Network Fundamentals, CCNA Exploration Guide, Mark A. Dye, Rick McDonald, Antoon W. Rufi, Cisco Press, 2008 Data Communications and Networikng, 6th edition, William Stalling, 2002 Network+, Computing Technology Industry Association, Syngress, Osborne, McGrawHill, 1999 Cabling : The Complete Guide to Network Wiring, 2nd Edition, David Groth, Sybex, 2001 ITE PC v4.1 Chapter 1
Objectives After completing this chapter, students will be able to: Explain how multiple networks are used in everyday life. Explain the topologies and devices used in a small- to mediumsized business network. Explain the basic characteristics of a network that supports communication in a small- to medium-sized business. Explain trends in networking that will affect the use of networks in small to medium-sized businesses.
End Devices Some examples of end devices are: Computers (work stations, laptops, file servers, web servers) Network printers VoIP phones TelePresence endpoint Security cameras Mobile handheld devices (such as smart phones, tablets, PDAs, and wireless debit / credit card readers and barcode scanners)
Supporting Network Architecture As networks evolve, we are discovering that there are four basic characteristics that the underlying architectures need to address in order to meet user expectations: Fault Tolerance Scalability Quality of Service (QoS) Security
Providing QoS Examples of priority decisions for an organization might include: Time-sensitive communication - increase priority for services like telephony or video distribution. Non time-sensitive communication - decrease priority for web page retrieval or email. High importance to organization - increase priority for production control or business transaction data. Undesirable communication - decrease priority or block unwanted activity, like peer-to-peer file sharing or live entertainment.
The concept of any device, to any content, in anyway is a major global trend that requires significant changes to the way devices are used. This trend is known as Bring Your Own Device (BYOD). Presentation_ID
Cloud Computing Cloud computing offers the following potential benefits: Organizational flexibility Agility and rapid deployment Reduced cost of infrastructure Refocus of IT resources Creation of new business models
Data Centers A data center is a facility used to house computer systems and associated components including: Redundant data communications connections High-speed virtual servers (sometimes referred to as server farms or server clusters) Redundant storage systems (typically uses SAN technology) Redundant or backup power supplies Environmental controls (e.g., air conditioning, fire suppression) Security devices
Security Threats The most common external threats to networks include: Viruses, worms, and Trojan horses Spyware and adware Zero-day attacks, also called zero-hour attacks Hacker attacks Denial of service (DoS) attacks Data interception and theft Identity theft
Properties of UTP Cabling UTP cable does not use shielding to counter the effects of EMI and RFI. Instead, cable designers have discovered that they can limit the negative effect of crosstalk by: Cancellation Varying the number of twists per wire pair
Properties of Fiber Optic Cabling Fiber-optic cabling is now being used in four types of industry: Enterprise Networks Fiber-to-the-home (FTTH) and Access Networks Long-Haul Networks Submarine Networks
• IEEE 802.15 standard • Supports speeds up to 3 Mb/s • Provides device pairing over distances from 1 to 100 meters. • IEEE 802.16 standard • Provides speeds up to 1 Gbps • Uses a point-to-multipoint topology to provide wireless broadband access.
Summary In this chapter, you learned: Networks and the Internet have changed the way we communicate, learn, work, and even play. Networks come in all sizes. They can range from simple networks consisting of two computers, to networks connecting millions of devices. The Internet is the largest network in existence. In fact, the term Internet means a ‘network of networks. The Internet provides the services that enable us to connect and communicate with our families, friends, work, and interests. The network infrastructure is the platform that supports the network. It provides the stable and reliable channel over which communication can occur. It is made up of network components including end devices, intermediate devices, and network media.
Summary (cont.) In this chapter, you learned: Networks must be reliable. Network security is an integral part of computer networking, regardless of whether the network is limited to a home environment with a single connection to the Internet, or as large as a corporation with thousands of users. The network infrastructure can vary greatly in terms of size, number of users, and number and types of services that are supported on it. The network infrastructure must grow and adjust to support the way the network is used. The routing and switching platform is the foundation of any network infrastructure.