TRINITY INSTITUTE OF PROFESSIONAL STUDIES

Sector – 9, Dwarka Institutional Area, New Delhi-75Affiliated to Institution of G.G.S.IP.U, Delhi

ADVANCED COMPUTER

NETWORK -20311ACN

TRINITY INSTITUTE OF PROFESSIONAL STUDIES

Sector – 9, Dwarka Institutional Area, New Delhi-75Affiliated to Institution of G.G.S.IP.U, Delhi

Advanced computer network

ACN-20311

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Network

• A network is a connected collection of devices and end systems, such as computers and servers, that can communicate with each other.

• Networks carry data in many types of environments, including homes, small businesses, and large enterprises. In a large enterprise, a number of locations might need to communicate with each other, and you can describe those locations as follows

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Locations

• Main office:• Remote locations• Branch offices:• Home offices:• Mobile users

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Resource-Sharing Functions and Benefits

• The main functions of computer networks in business today are to simplify and streamline business processes through the use of data and application sharing. Networks enable end users to share both information and hardware resources. By providing this interconnection between the users and common sets of data, businesses can make more efficient use of their resources. The major resources that are shared in a computer network include the following:

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Resource sharing

• Data and applications: When users are connected through a network, they can share files and even software application programs, making data more easily available and promoting more efficient collaboration on work projects.

• Physical resources: The resources that can be shared include both input devices, such as cameras, and output devices, such as printers.

• Network storage: Today the network makes storage available to users in several ways. Direct attached storage (DAS) directly connects physical storage to a PC or a shared server. Network attached storage (NAS) makes storage available through a special network appliance. Finally, storage area networks (SAN) provide a network of storage devices.

• Backup devices: A network can also include backup devices, such as tape drives, that provide a central means to save files from multiple computers. Network storage is also used to provide archive capability, business continuance, and disaster recovery.

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Network User Applications

• E-mail: E-mail is a valuable application for most network users. Users can communicate information (messages and files) electronically in a timely manner, to not only other users in the same network but also other users outside the network (suppliers, information resources, and customers, for example). Examples of e-mail programs include Microsoft Outlook and Eudora by Qualcomm.

• Web browser: A web browser enables access to the Internet through a common interface. The Internet provides a wealth of information and has become vital to the productivity of both home and business users. Communicating with suppliers and customers, handling orders and fulfillment, and locating information are now routinely done electronically over the Internet, which saves time and increases overall productivity. The most commonly used browsers are Microsoft Internet Explorer, Netscape Navigator, Mozilla, and Firefox.

• Instant messaging: Instant messaging started in the personal user-to-user space; however, it soon provided considerable benefit in the corporate world. Now many instant messaging applications, such as those provided by AOL and Yahoo!, provide data encryption and logging, features essential for corporate use.

• Collaboration: Working together as individuals or groups is greatly facilitated when the collaborators are on a network. Individuals creating separate parts of an annual report or a business plan, for example, can either transmit their data files to a central resource for compilation or use a workgroup software application to create and modify the entire document, without any exchange of paper. One of the best-known traditional collaboration software programs is Lotus Notes. A more modern web-based collaboration application is a wiki.

• Database: This type of application enables users on a network to store information in central locations (such as storage devices) so that others on the network can easily retrieve selected information in the formats that are most useful to them. Some of the most common databases used in enterprises today are Oracle and Microsoft SQL Server.

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Characteristics of a Network

• Speed: Speed is a measure of how fast data is transmitted over the network. A more precise term would be data rate.

• Cost: Cost indicates the general cost of components, installation, and maintenance of the network.

• Security: Security indicates how secure the network is, including the data that is transmitted over the network. The subject of security is important and constantly evolving. You should consider security whenever you take actions that affect the network.

• Availability: Availability is a measure of the probability that the network will be available for use when required. For networks that are meant to be used 24 hours a day, 7 days a week, 365 days a year, availability is calculated by dividing the time it is actually available by the total time in a year and then multiplying by 100 to get a percentage.

• Scalability: Scalability indicates how well the network can accommodate more users and data transmission requirements. If a network is designed and optimized for just the current requirements, it can be very expensive and difficult to meet new needs when the network grows.

• Reliability: Reliability indicates the dependability of the components (routers, switches, PCs, and so on) that make up the network. Reliability is often measured as a probability of failure, or mean time between failures (MTBF).

• Topology: Networks have two types of topologies: the physical topology, which is the arrangement of the cable, network devices, and end systems (PCs and servers), and the logical topology, which is the path that the data signals take through the physical topology.

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Unit – IFoundation

• Building network• framing error detection In serial communications, a framing error is the result of reading a string of symbols which are grouped in blocks at the wrong

starting point.• Reliable transmission• Ethernet &MAC Internetworking A networking interface allows a computer or mobile device to connect to a local area network (LAN) using

Ethernet as the transmission mechanism.

• Switching & Bridging• Basic Internetworking• Routing Routing is usually performed by a dedicated device called a router. It provide best and shortest

path to data on the network

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

Unit-IIAdvance Internetworking

• The global Internet• Multicast To transmit a single message to a select group of recipients.

• MPLS(Multiprotocol Label Switching) MPLS gives network operators a great deal of flexibility to divert and route traffic around link failures, congestion, and bottlenecks.

• Routing among mobile Devices• Simple Demultiplexer A multiplexer accepts two (or more) streams of data and combines them into one stream. The mixed data streams must be

separated. This is done by demultiplexers.

• Reliable Byte Stream (TCP) A byte stream is a bit stream, in which data bits are grouped into units, called bytes. Reliable delivery of byte stream by TCP.

• RPC(remote procedure call) RPC is a powerful technique for constructing distributed, client-server based applications.

• RTP The Real-time Transport Protocol (RTP) defines a standardized packet format for delivering audio and video over IP networks. RTP

is used extensively in communication and entertainment systems that involve streaming media, such as telephony, video teleconference applications, television services and web-based push-to-talk features.

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

UNIT IIICongestion Control & Resource Allocation

• TCP CongestionControl Avoidance mechanisms• Quality of Service.• Multimedia Networking Using networks different users on different machines can share image, sound,

video, voice and many other features and to communicate with each under these tools.

• Multimedia networking applications 1) stored streaming 2) live streaming 3) interactive, real-time

• RTSP, RTCP, SIP, H.323

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

UNIT IVNetwork Security

• Cryptographic Building Blocks There are various techniques for encrypting messages, for securely exchanging keys, for maintaining the integrity of messages, and

for guaranteeing authenticity of a message. These tools can be thought of as building blocks to construct protection against attack.• Symmetric Key Encryption

An encryption system in which the sender and receiver of a message share a single, common key that is used to encrypt and decrypt the message. Symmetric-key cryptography is sometimes called secret-key cryptography

• Public Key Encryption A cryptographic system that uses two keys -- a public key known to everyone and a private or secret key known only to the recipient of

the message.• Authentication protocols An authentication protocol is a type of cryptographic protocol with the purpose of authenticating entities wishing to communicate

securely. Example Kerberos, Password Authentication Protocol (PAP), Extensible Authentication Protocol (EAP)

• PGP• is a data encryption and decryption computer program that provides cryptographic privacy

and authentication for data communication.• TLS, SSL• Firewalls• Intrusion Detection

TRINITY INSTITUTE OF PROFESSIONAL STUDIESSector – 9, Dwarka Institutional Area, New Delhi-75

• REFERENCE BOOKS:• [R1] Computer Networking: A Top Down

Approach (Fifth Edition), James F. Kurose

• W. Stallings, Networks Security Essentials: Application & Standards, Pearson Education, 2000