Networks and Communication Networks and Communication Systems in Distance LearningSystems in Distance Learning

ENTER

BY

MOZA AL-MAMARI

ID : 200411984

Supervisor:-Dr : NAEEM

GeneralGeneral Network Network

Simply, a network is a collection of computers, printers, and other electronic devices, linked by cables or wireless, allowing them to communicate with each other.

1-What is a Network ?

2-How networking made simple ?

Simply network is about fibers optic connected buildings and colleges with each others and UTP cables connected rooms' inside3 building with each others beside some wireless network in some places.

3-How network security is important in terms of networking? It is very important because without security no one can do anything in professional way without security and also to protect the users data from loss ior damage or steel .

4-What is the types of device servers? Switches, access points, routers .

5-Who is maintaining it?

Technicians & Warranty ((companies)) .

6-What network software you are using to maintain it?

Network analyzer and Monitoring system .

7-What is kind of network and level you are applying to make it really secure? High level of security included wired and wireless networks .

8-Do you have any hacking event?

Hacking available any where and you nothing is secure 100% but keep updating your security rules & policies .

9-Are you using site filtering software if so what’s its name?

Yes. You should filter the internet sites that don't meet our culture or it is dangerous to spread it out for public.

10-What kind of criteria you use to block illegal sites?

The way of blocking the unwanted sites or illegal sites is by defining filters in your proxy system then applies this filters to all incoming websites and the proxy will understand the sites required to be blocked.

11-How we can benefit from networking ?

In big organization like a university you have about 10000 students and you want them to connect to internet or Emails or locating their files in the server or watch some educational materials located some where in the Campus.

12-How do you maintain its security ?Security is long process and you have to set security rules at your organization then start applying your rules .

13-How frequently you change your passwords and advise to students and staff to do so?

Some security expert advice the users to change every month or every two weeks.

14-How data is securely passing through you network?

This is depending of security that employed in your network. In general most of the new network devices such switches, access point, routers have a deferent level of security and allow the network administrator to select what is the best fit in his environment.

Computer Network

An electronic medium through which computers are able to share applications, peripherals and other computer resources

The Network

First things first. You need to know what this thing is. Quite simply, a network is simply a group of two or more personal computers linked together. When configured in this way, the PC’s can share files, use a common printer or modem, etc.

There are many different network types. Let’s run through them here in order to define these terms for you.

network types

Local Area Network (LAN) : This is a network of computers that spans a relatively small space. Common LANs would be in an office or home. Wide Area Network (WAN) : This is a network that spans a larger area. It consists of two or more LANs connected to each other via telephone lines or some other means of connection.

Ethernet : a type of LAN. It is more or less a LAN protocol developed by Xerox Corporation back in 1976. We will get into more specifics later. Metropolitan Area Network (MAN) : This is a term not used as often. Nonetheless, this is a network that spans a town or city, usually connected by fiber optic cable, so it boasts high speeds. LAN : Short for virtual LAN, a network of computers that behave as if they are connected to the same wire even though they may actually be physically located on different segments of a LAN. The Internet is a system of linked networks that are worldwide in scope and facilitate data communication services such as remote login, file transfer, electronic mail, the World Wide Web and newsgroups.

With the advancements made in browser-based software for the Internet, many private organizations are implementing intranets. An intranet is a private network utilizing Internet-type tools, but available only within that organization. For large organizations, an intranet provides easy access to corporate information for employees.

Ring is another form of network configuration which differs from Ethernet in that all messages are transferred in a unidirectional manner along the ring at all times. Data is transmitted in tokens, which are passed along the ring and viewed by each device.

Network control panelIn general, a network control panel refers to a software program connected a group of networked computers and/or network devices with the ability to control and manage those network devices When referring to Microsoft Windows, the network control panel refers to the network option within the control panel.

Common Network Models

Client/server Model

Peer to Peer Model

Peer to Peer Model

Network Operating SystemsSoftware that allows these models

to operate to share resources across the networkClient/Server--Novell Netware & Windows NT, each has two parts, client and serverPeer to Peer--Windows for workgroups, Windows95, Netware Lite, LANtastic.

Network Cabling

Coaxial CableUnshielded Twisted

Pair (UTP)• Category 1-5 -- 5 is

bestFiber Optic Cable

Network Cabling model

Wireless Technology

MicrowaveInfraredSatelliteCellular or Spread SpectrumRadio

Internetworking Devices

RepeatersBridgesRouters

Routers

Device that is typically used to connect networks that use multiple protocols and topologiesAKA “gateway”“smart” bridgecontrols “traffic” and limits access .

Repeater

Device that gives network signals a “boost” so they can travel farther

It repeats the signal near the end of its range.

Bridge

Device that connects two networks so that they act as if they are one networkusually connects like networks: Ethernet to Ethernet, etc.“smart” repeater: monitors and limits “traffic .”

Firewall

“hotest” piece of networking equipmentSits outside the main network to limit accessA security device with definitive “rules” for access.

Internet

The world’s largest networkAn infrastructure for transporting dataA huge “network or networks”Uses TCP/IP protocolNOT a single application, but an infrastructure for E-mail, Web, etc.

Network Topology

Bus (traditional Ethernet)StarToken-ring

In bus topology, all nodes are connected to a central cable which is called a bus. A message (signal) that is sent by a node travels along the bus through all other nodes. When the signal passes by a node, the node checks its destination address.

Network Topology

In star topology, all nodes are connected to a central point which is called a hub. A sending node transmits its message (signal) to the hub. The hub then retransmits the signals to all other nodes. Each receiving node checks the signal's destination address, if it matches the node's address it processes the signals.

Network Topology

In ring topology, each node is connected to two nearby nodes and the overall configuration forms a loop. A ring network doesn't introduce a single point of failure but it is relatively more expensive. Token Ring network is an example of LAN technology that uses ring topology.

Network Topology

star

bus

ring