RemHardware Practice and Networks

In this network survey, my main idea of this scenario is that I find it very interesting and very needful to deal with our network. The main purposes in my opinion by   having this survey are two basic reasons which I personally identify in the networks and find them very serious are the following ones:

a) The stability of the network: The stability of the network plays the most important role of a network. Unfortunately we face and identify problems with our network very often. The frequent reason why this usually happens and   is largely due is because the network overloads. Therefore our goals always in a network is to try and have a more successful and efficient network by minimizing the errors in the network. In this case to achieve our goal by doing that and to improve our uptime performance, there are some programs which are designed and available to monitor the uptime and the stability of the network. One of them for an example is the PRTG Network monitoring which provides us the ability and updates of the networks status. If the program identifies a serious problem in our network it will let us know about it and we'll be able to fix afterwards.

b) The security of the network:  The network security is generally taken as providing protection at the boundaries of an organization by keep out hackers. Unfortunately in networks we deal with intruders (hackers) very often. A hacker's goal is always to try   to attack our network with different kinds of ways which if that happens (accesses in the network) that can cost us a lot of damage which means after that he can continent and continuous monitoring our network for an example. Therefore security also always plays a basic role in a network. By using different techniques and security management we have the ability to defend the hackers from those attacks / threats.  Some of the basic  defenders and ways we use in this case are the following ones:

1. A strong firewall and proxy to keep unwanted people out of   the network.
2. Internet security software suites and strong Anti-Virus Soft wares.
3. Wireless connections which lead to the wire walls.

My Opinion about our network in AMC:

I believe that the network in our college works quiet well. However  unfortunately the network goes down every once in a while probably due to overloading.  Also, I've realized that our network isn't that fast (works with 8Mbps) in order to cover any additional  requirements we have but I must say that its satisfactory for the student area.

Section 2

                           Descriptions of all Network Types:

a) LAN (Local Area Network):  The LAN network is a computer network which covers small physical areas such as homes, offices, small groups of buildings, such as schools for an example. The defining characteristics of  LANs, in contrast to wide-area networks include their usually higher data-transfer rates, lack of a need of telecommunication lines, and smaller geographic areas.

Ø The characteristics of  Different Types (LANs)

· Topology : The geometric  arrangement of the devices on the network

· Media: The devices can be connected by twisted pair, fibre-optical cables, or   coaxial wires.

· Protocols:  The encoding specifications and the rules for sending data.

· Number of  LANs:  The account standard is 24.

The most common network Protocol types which are implemented  in LANs:

Ethernet

The Ethernet protocol is by far the most widely used. Ethernet uses an access method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection). This is a system where each computer listens to the cable before sending anything through the network. If the network is clear, the computer will transmit. If some other node is already transmitting on the cable, the computer will wait and try again when the line is clear. Sometimes, two computers attempt to transmit at the same instant. When this happens a collision occurs. Each computer then backs off and waits a random amount of time before attempting to retransmit. With this access method, it is normal to have collisions. However, the delay caused by collisions and retransmitting is very small and does not normally effect the speed of transmission on the network.

The Ethernet protocol allows for linear bus, star, or tree topologies. Data can be transmitted over wireless access points, twisted pair, coaxial, or fiber optic cable at a speed of 10 Mbps up to 1000 Mbps.

Fast Ethernet

To allow for an increased speed of transmission, the Ethernet protocol has developed a new standard that supports 100 Mbps. This is commonly called Fast Ethernet. Fast Ethernet requires the use of different, more expensive network concentrators/hubs and network interface cards. In addition, category 5 twisted pair or fiber optic cable is necessary. Fast Ethernet is becoming common in schools that have been recently wired.

Local Talk

Local Talk is a network protocol that was developed by Apple Computer, Inc. for Macintosh computers. The method used by Local Talk is called CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance). It is similar to CSMA/CD except that a computer signals its intent to transmit before it actually does so. Local Talk adapters and special twisted pair cable can be used to connect a series of computers through the serial port. The Macintosh operating system allows the establishment of a peer-to-peer network without the need for additional software. With the addition of the server version of AppleShare software, a client/server network can be established.

The Local Talk protocol allows for linear bus, star, or tree topologies using twisted pair cable. A primary disadvantage of Local Talk is speed. Its speed of transmission is only 230 Kbps.

Token Ring

The Token Ring protocol was developed by IBM in the mid-1980s. The access method used involves token-passing. In Token Ring, the computers are connected so that the signal travels around the network from one computer to another in a logical ring. A single electronic token moves around the ring from one computer to the next. If a computer does not have information to transmit, it simply passes the token on to the next workstation. If a computer wishes to transmit and receives an empty token, it attaches data to the token. The token then proceeds around the ring until it comes to the computer for which the data is meant. At this point, the data is captured by the receiving computer. The Token Ring protocol requires a star-wired ring using twisted pair or fiber optic cable. It can operate at transmission speeds of 4 Mbps or 16 Mbps. Due to the increasing popularity of Ethernet, the use of Token Ring in school environments has decreased.

FDDI

Fiber Distributed Data Interface (FDDI) is a network protocol that is used primarily to interconnect two or more local area networks, often over large distances. The access method used by FDDI involves token-passing. FDDI uses a dual ring physical topology. Transmission normally occurs on one of the rings; however, if a break occurs, the system keeps information moving by automatically using portions of the second ring to create a new complete ring. A major advantage of FDDI is speed. It operates over fiber optic cable at 100 Mbps.

ATM

Asynchronous Transfer Mode (ATM) is a network protocol that transmits data at a speed of 155 Mbps and higher. ATM works by transmitting all data in small packets of a fixed size; whereas, other protocols transfer variable length packets. ATM supports a variety of media such as video, CD-quality audio, and imaging. ATM employs a star topology, which can work with fiber optic as well as twisted pair cable.

ATM is most often used to interconnect two or more local area networks. It is also frequently used by Internet Service Providers to utilize high-speed access to the Internet for their clients. As ATM technology becomes more cost-effective, it will provide another solution for constructing faster local area networks.

Gigabit Ethernet

The most recent development in the Ethernet standard is a protocol that has a transmission speed of 1 Gbps. Gigabit Ethernet is primarily used for backbones on a network at this time. In the future, it will probably be used for workstation and server connections also. It can be used with both fiber optic cabling and copper. The 1000BaseTX, the copper cable used for Gigabit Ethernet, is expected to become the formal standard in 1999.

Compare the Network Protocols

Network Diagramming Software

The Reference of the characteristics of the protocol types which we can find were in the following website:

http://www.edrawsoft.com/Network-Protocol.php

Virtual LAN (VLAN): A Virtual LAN, commonly known as a VLAN, is a group of hosts with a common set of requirements that communicate as if they were attached to the same broadcast domain, regardless of their physical location. A VLAN has the same attributes as a physical LAN, but it allows for end stations to be grouped together even if they are not located on the same network switch. Network reconfiguration can be done through software instead of physically relocating devices.

The Reference is available to see in the following website:

http://en.wikipedia.org/wiki/Virtual_LAN

Ø Â  Topologies and types of wires we use in LAN Networks: 

                     i) Star

                    ii) Bus

                                         Iii) Ring

Wires:  i) STP

             ii) UTP

             iii) FTP

                        iv) Coaxial

The   Reference is available to see in the following website :   http://en.wikipedia.org/wiki/LAN

b) MAN (Metropolitan Area Network): The MAN network is optimized for a larger geographical area than a LAN. It' s a network that usually spans a  large Campus, cities, buildings, several blocks etc. The MAN networks can also depend on communications channels of moderate to high data rates. A MAN might be operated and owned by a single organization, but it usually will be used by many individuals and organizations. They can also be operated and owned by public utilities as well.

Ø Characteristics of MAN:

· It typically covers an area of between 5 and 50km. The network size falls between LANs and WANs.

· It is frequently used to provide   a share connection to another connection using a link to a WAN.

· A MAN is not generally owned by a single organization. It's communication links and equipment are generally owned by either a consortium of users or by a single network provider who sells the service to the users

The References are available to see in the following websites:

http://answers.yahoo.com/question/index?qid=20090614031036AAN740S

http://en.wikipedia.org/wiki/Metropolitan_area_network

c) WAN (Wide Area Networks):  The WAN networks are networks which cover a broad area (any networks which links cross, national boundaries, metropolitan or regional). This is a contrast with local area networks, with metropolitan area networks, with personal area networks or campus area networks, which are usually limited to buildings, rooms, specific metropolitan areas etc.

Ø Characteristics of WANs:

· Wide - Area LAN that utilizes a high speed Layer 2 Switch

· Connects Multiple LANs via an Ethernet network

· Compatible with a Variety of Access lines.

The References are available to see in the following websites:

http://answers.yahoo.com/question/index?qid=20090614031036AAN740S

http://en.wikipedia.org/wiki/Wide_Area_Network

d) Fibre Networks: Fibre networks are privately operated optical fibre network that is run directly by its operator over dark fibre purchased or leased from another supplier, rather than by bandwidth or leased line capacity. These kinds of networks are usually used for private networking or internet infrastructure networking. The dark Fibre can operate using the latest optical protocols (wavelength division multiplexing) to add capacity where needed and to provide without removing the network from service an upgrade path between technologies. The dark fibre networks can be point to point, point to multipoint or use self-healing ring.

Ø Also to label basic information about the fibre networks, these networks are very more expensive than all the others. 

The Reference is available to see in the following website:   http://en.wikipedia.org/wiki/Dark_fibre_network

MS VISIO NETWORK DIAGRAMS

Types of networks:

LANs:

Ring Topology ( IEEE802.5 Protocol):

In the ring topology, each computer is connected to the network in a closed up loop. All computers regardless of topology   has its own IP address for identification purposes that. All of these computers are connected to this ring on one and only direction. The disadvantages in this topology are:

a) When one computer transmits every other computer listens. When a computer sends a data package to another it has to follow the whole launch until the receiver (computer) gets it which means that there's big traffic in the network. The reason why this happens is the fact that only one computer can transmit on the network at a time

b) The second big disadvantage of the ring topology is that when a computers wire gets cut, then the whole network goes down.

Bus Topology:

The bus network connects each computer to a single segment truck such as coax cable, communication lines etc. In this case, the transportation starts from one side of the bus and ends on the other side of it. In this network we also use an access method which is called   CSMA/MA which is used to control / handle the collision which can occur in case two signals are placed on the same wire at the same time. However the bus topology we must say that it's very well suited for temporary networks and also are easy to extend and implement. Although unfortunately a few disadvantages are identified as well in the bus network which a few of them are  :

i) The maintenance cost may be higher in the  future

ii) Very difficult to administer

iii) A cable cut can turn down the whole network (disable)

iv) Limited number of stations.

General Comment: In bus topology the transmission starts in one side of the bus and continues sequentially until it reaches the end. An access method is used to control, prevent and handle any collision that may happen during communication. This method is called CSMA/MA.

Star Topology( IEEE 802.3 Protocol):

In this case, the star topology network consists of one central hub, switch or computer (chosen the switch in the topology diagram) which acts as a conduit to transmit messages. In this topology if one computer wants to send a data package to another, it send it to the central switch or computer and that sends the package to the receiver after. In that way we have a fast data transmission in small timing. The advantage about the star topology comparing to the other topologies is that even if a computers wire gets cut or the computer shuts down for some reason, the network will continue working perfectly without that affecting it. That's why the star topology is more successful as a network and it's often more preferred than the other ones.

General Comments:

1) The purpose of the switch is to direct the traffic of all messages and verify the boundaries of virtual LANs. Smart switches allow us to design VLANs and therefore Group PCs in different groups under the same subnet granting each group different security writes.

2) The PCs can work independently and be connected or disconnected to the network without affecting the rest of the PCs. This eliminates any wiring problem that may arise at any given time to any given PC.

A WAN  Network which acts like a MAN Network and uses Fibre Optics:

Description of this Network:

As we can see in the diagram, our network consists of:

a) 5 routers

b) 5 buildings ( Universities)

c) 1 Firewall which gives us access to the Internet.

General view of the network:

However in the network every building is connected to a router except in one case (down on the right) we have two buildings connected on one router and the router we placed in the centre of the four routers. The four routers we see in the diagram connect to the centred router which then connects with a Firewall

What are routers?

Routers are networking devices whose hardware and software are usually tailored to the tasks of routing and forwarding info. They connect two or more logical subnets which don't necessarily map 1 to 1 to the physical interfaces of the router.

"What is the Ethernet" ?

Ethernet is a family of framed based computer networking technologies which are used in Local Are Networks (LANs). Ethernet is standardized as IEEE 802.3 and is the most widespread wired LAN technology for almost 30 years now ( around 1980).

The connection wires we used:

The connection wires we used in this network were fibre optics. These wires are plastic/glass which carries light along their length. The reason why we used them to materialize our network is because signals travel along with them with less loss (we have 10Gig E in our case) and permit transmission over longer distances and higher bandwidth (data rates) than other forms of communication.

Firewall:  The firewall is one of the most important parts in a network. They're implemented in either software or hardware or even a combination of both and they are usually needed in networks (especially big ones) to prevent unauthorized Internet users from accessing private networks connected to the internet.

Why does this network also acts like a MAN?

This network also acts like a MAN because it's been spanned   in a city which are ranged from several blocks of buildings.

SECTION 3

               The University's Network drawn in MS VISIO:

General Description of the Network:

This is a typical network isolation example using firewall and managed switch in VLAN configuration. In VLAN configuration the one network is isolated from the other, and therefore users on one network don't have access to the other.

The diagram also depicts the outside WAN address (192.168.100.xxx) coming into the firewall, and the two local networks (192.16.80.xxx & 192.16.90.xxx). This example shows that the WAN address is, and should be, in different subnet than the local networks.

The firewall and VLAN combination is best suited for areas like hotels for example, where the one network could be for customers only, access the internet, and the other is for the management offices, reception and logistics.

In our specific example, the company network (192.16.80.xxx) is isolated via VLAN switches from the educational (192.16.90.xxx) network. This is due to the fact that the students at the PC labs or lecture rooms don't have a need to access the servers 'db or controller.

Note :  Security writes / permissions do not replace the VLAN isolation. Permissions come on top of VLANs and enhanced them, as long as they're in the same subnet.

More details:

As we can see from the top of drawing, our network begins with a connection on an ADSL Router with a firewall. The reason why the firewall is installed in a network generally is to protect our network from the outside world (hackers) and defend our network from their attacks. Continuing, we see that the firewall connects with two different VLAN switches with two different IP addresses which are named as company (172.16.80.0 /24) and Edu (172.16.90.0 /24). Therefore on the company's network switch we have two servers connected which are the Mail Server (Connects with IEK AKMH) and the Web Server. However on the second network line (Edu) we see that the switch connects with a VLAN Router with two lines (172.16.80.5 /24, 172.16.90.5/24à The reason why this exists is to protect our Domains), Library switch ,Lab A2 switch, A4 switch, Edu Domain Controller, Database Server and Comp. Domain Controller. 

· The VLAN Router connects with the LMDS AMC Router and then the LMDS AMC Router connects with the LMDS IEK ( with a dedicated line) in order for the  network communication of them two.

· In the library switch,   all the library computers are connected on the switch in order to have access to the Internet.

· In the Lab A2 switch,  all of the A2 labs computers are connected on the A2 switch in order to have access to the internet.

· Switch A4 provides 3 lines. One to switch A3, one to an Access Point and one to Lab A4. In the A3 switch, all the computers which are in lab A3 are connected on that switch in order to have access to the internet. The Access Point provides wireless signal to all the theoretical Lecture classes in order to have access to the internet. All the computers in A4 Lab are directly connected to Switch A4 which provides them access to the internet.

Edu Domain Controller:  It's a server which responds to security authentication requests such as logging in, checking permissions within the Windows Server Domain.

Database Server:  A database server is a computer program that provides database services to other computer programs or computers, as defined by the client-server model. The term may also refer to a computer dedicated to running such a program. Database management systems frequently provide database server functionality, and some DBMSs (e.g., MySQL) rely exclusively on the client-server model for database access.

Reference for the Database Server information available to see in the following website of Wikipedia:

http://en.wikipedia.org/wiki/Database_server

Web Server: A Web server is a computer program that delivers (serves) content, such as Web pages, using the Hypertext Transfer Protocol (HTTP), over the World Wide Web. The term Web server can also refer to the computer or virtual machine running the program. In large commercial deployments, a server computer running a Web server can be rack-mounted in a server rack or cabinet with other servers to operate a Web farm.

Reference for the Web Server information available to see in the following website of Wikipedia:

http://en.wikipedia.org/wiki/Web_server

Hardware components which were used in this network:

1. 1 ADSL Modem
2. 1 Firewall
3. 6 Switches
4. 3 Routers
5. 1 Access Point
6. Mail Server, Web Server, Edu Domain Controller, Database Server, Comp. Domain Controller.
7. Computers in Labs A2,A3,A4 & in the Library

Descriptions of Hardware components:

ADSL Modem:  A Digital Subscriber Line (DSL) modem is a device used to connect a computer or router to a telephone circuit that has Digital Subscriber Line service configured. Like other modems, it is a type of transceiver. It is also called a DSL Transceiver or ATU-R (for ADSL Transceiver Unit-Remote). The acronym NTBBA, which stands for network termination broad band adapter) is also common in some countries.

Some DSL modems also manage the connection and sharing of the DSL service in a network, in this case, the unit is termed a DSL router or residential gateway. DSL routers have a component that performs framing, while other components perform Asynchronous Transfer Mode Segmentation and Reassembly, IEEE 802.1D bridging and/or IP routing. Typical user interfaces are Ethernet and Universal Serial Bus (USB). Although an DSL modem working as a bridge does not need an IP address, it may have one assigned for management purposes.

Reference for the ADSL Modem information is available to see in the following website:

http://en.wikipedia.org/wiki/DSL_modem

Switch: a switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another. The most familiar form of switch is a manually operated electromechanical device with one or more sets of electrical contacts. Each set of contacts can be in one of two states: either 'closed' meaning the contacts are touching and electricity can flow between them, or 'open', meaning the contacts are separated and no conducting.

A switch may be directly manipulated by a human as a control signal to a system, such as a computer keyboard button, or to control power flow in a circuit, such as a light switch. Automatically-operated switches can be used to control the motions of machines, for example, to indicate that a garage door has reached its full open position or that a machine tool is in a position to accept another workpiece. Switches may be operated by process variables such as pressure, temperature, flow, current, voltage, and force, acting as sensors in a process and used to automatically control a system.

Reference for the Switch information is available to see in the following website:

http://en.wikipedia.org/wiki/Switch

Routers: Routers are networking devices whose hardware and software are usually tailored to the tasks of routing and forwarding info. They connect two or more logical subnets which don't necessarily map 1 to 1 to the physical interfaces of the router.

Access Point:

In computer networking, a wireless access point (WAP) is a device that allows wireless communication devices to connect to a wireless network using Wi-Fi, Bluetooth or related standards. The WAP usually connects to a router, and can relay data between the wireless devices (such as computers or printers) and wired devices on the network.

Industrial grade WAPs are rugged, with a metal cover and a DIN rail mount. During operations they can tolerate a wider temperature range, high humidity and exposure to water, dust, and oil. Wireless security includes: WPA-PSK, WPA2, and IEEE 802.1x/RADIUS, WDS, WEP, TKIP, and CCMP (AES) encryption. Unlike home consumer models, industrial wireless access points can also be used as a bridge, router, or a client.

Reference for the Access Point information is available to see in the following website:

http://en.wikipedia.org/wiki/Access_point

Associated Standards:

RLOGIN: is a software utility for Unix-like computer operating systems that allows users to log in on another host via a network, communicating via TCP port 513.

Reference is available to see in the following website: http://en.wikipedia.org/wiki/Rlogin

RTSP: The Real Time Streaming Protocol (RTSP) is a network control protocol designed for use in entertainment and communications systems to control streaming media servers. The protocol is used to establish and control media sessions between end points.

Reference is available to see in the following website: http://en.wikipedia.org/wiki/RTSP

SCTP: In computer networking, the Stream Control Transmission Protocol (SCTP) is a Transport Layer protocol, serving in a similar role as the popular protocols Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).

Reference is available to see in the following website: http://en.wikipedia.org/wiki/SCTP

SLP: The Service Location Protocol (SLP, srvloc) is a service discovery protocol that allows computers and other devices to find services in a local area network without prior configuration. SLP has been designed to scale from small, unmanaged networks to large enterprise networks. It has been defined in RFC 2608 as Standards Track document.

Reference is available to see in the following website: http://en.wikipedia.org/wiki/Service_Location_Protocol

SMPP: The Short Message Peer-to-Peer (SMPP) protocol is a telecommunications industry protocol for exchanging SMS messages between SMS peer entities such as short message service centers and/or External Short Messaging Entities.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/SMPP

SMTP: Simple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (e-mail) transmission across Internet Protocol (IP) networks. SMTP was first defined in RFC 821 (STD 15) (1982)[1], and last updated by RFC 5321 (2008) which includes the extended SMTP (ESMTP) additions, and is the protocol in widespread use today

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/SMTP

SNMP: Simple Network Management Protocol (SNMP) is a UDP-based network protocol. It is used mostly in network management systems to monitor network-attached devices for conditions that warrant administrative attention. SNMP is a component of the Internet Protocol Suite as defined by the Internet Engineering Task Force (IETF). It consists of a set of standards for network management, including an application layer protocol, a database schema, and a set of data objects.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/SNMP

TCP/IP: The Internet Protocol Suite (commonly known as TCP/IP) is the set of communications protocols used for the Internet and other similar networks. It is named from two of the most important protocols in it: the Transmission Control Protocol (TCP) and the Internet Protocol (IP), which were the first two networking protocols defined in this standard. Today's IP networking represents a synthesis of several developments that began to evolve in the 1960s and 1970s, namely the Internet and LANs (Local Area Networks), which emerged in the mid- to late-1980s, together with the advent of the World Wide Web in the early 1990s.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/TCP/IP

IPX/ SPX: IPX/SPX stands for Internetwork Packet Exchange/Sequenced Packet Exchange. IPX and SPX are networking protocols used primarily on networks using the Novell NetWare operating systems.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/IPX/SPX

IEEE

-The Institution of Electrical and Electronics Engineers

-IEEE sets standards for most types of electrical interfaces. Its most famous standard is probably RS-232C, which defines an interface for serial communication.

•IET (formerly IEE)

-The Institution of Engineering and Technology

•ITU

-The International Telecommunication Union

-It has defined a number of standards, including V.22, V.32, V.34, V.42 and V.90, that specify protocols for transmitting data over telephone lines.

•ISO

-The International Standards Organization

-Open Standards Interconnection â€-7-Layer' Model

Wireless Hardware Components:

ü Wireless Routers

ü Access Points

ü Wireless Antennas ( point to point,  point to multipoint)

ü Feeder Antennas

ü Wireless Network Cards which are installed in computers

Wired Hardware Components:

ü Routers

ü Switches/ Hubs

ü Network Adaptors

ü Cables ( Ethernet)

ü Network Cards which are installed in computers

                      My Home Network Diagram in MS Visio:

Description-Comment:

I have three computers and one print in my house installed on a Router device ( which gives access to the internet) with the 3 computers and printer having their different IP's but the same Gateway (Routers IP: 192.168.1.1). The printer which I also added/connected on the network serves all three of my computers.

· SECTION 4

                  University's Software Components:

ü Windows Server 2003& 2008( which are installed in the computerization rooms and which the University's IT handles/works it)

ü Windows XP Professional ( which are installed in computer labs for the students, library, rest offices)

Homes Software Components:

ü Windows XP Professional

Software associated Standards: IEEE 10 Base T and 10 Base 2

Wireless Software Standards:

ü IEEE 802.11: IEEE 802.11 is a set of standards carrying out wireless local area network (WLAN) computer communication in the 2.4, 3.6 and 5GHz frequency bands. They are created and maintained by the IEEE LAN/MAN Standards Committee (IEEE 802).

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/IEEE_802.11

ü WPA: Wi-Fi Protected Access (WPA and WPA2) is a certification program developed by the Wi-Fi Alliance to indicate compliance with the security protocol created by the Wi-Fi Alliance to secure wireless computer networks. The Alliance defined the protocol in response to several serious weaknesses researchers had found in the previous system, WEP (Wired Equivalent Privacy)  .

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/Wi-Fi_Protected_Access

ü CSMA/CA: CSMA/CA is used where CSMA/CD cannot be implemented due to the nature of the channel. CSMA/CA is used in 802.11 based wireless LANs and in 802.15.4 based wireless PANs.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/CSMA/CA

ü HIPER LAN 1 , 2: HiperLAN (High Performance Radio    LAN) is a Wireless LAN standard. It is a European alternative for the IEEE 802.11 standards (the IEEE is an international organization). It is defined by the European Telecommunications Standards Institute (ETSI). In ETSI the standards are defined by the BRAN project (Broadband Radio Access Networks). The HiperLAN standard family has four different versions.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/HiperLAN

Wired Software Standards:

ü CSMA/CD:Carrier Sense Multiple Access With Collision Detection (CSMA/CD), in computer networking, is a network access method in which

• a carrier sensing scheme is used.
• a transmitting data station that detects another signal while transmitting a frame, stops transmitting that frame, transmits a jam signal, and then waits for a random time interval (known as "back off delay" and determined using the truncated binary exponential back off algorithm) before trying to send that frame again.

Reference is available to see in the following website:

http://en.wikipedia.org/wiki/CSMA/CD

Wireless software Components:

ü Protocol 801.A/B/G/N

ü Drivers for wireless devices

ü Software Wireless Network Monitoring

ü QS Security ( WPA, WPE)

Wired software components:

ü Protocol TCP/IP

ü Drivers for devices

· SECTION 5

Design of the A2 Computer Lab on MS Visio:

Description:

As we can see in the diagram we realize that all the computers in the A2 lab are connected with Ethernet cables on a switch and every computer has its own IP address in the network. The switch as we saw in the whole network diagram we made, we see that it connects on the VLAN switch. The VLAN switch afterwards is connected on the firewall, the firewall on the ADSL Modem and therefore we have access to the internet. Showing summary a drawing of the connectivity:

Design of the A3 Computer lab on MS Visio:

Description:

As we can see in the diagram we realize that all the computers in the A3 lab are connected with Ethernet cables on a switch and every computer has its own IP address in the network. The switch as we saw in the whole network diagram we made, we see that it connects on theA4 lab switch. The A4 Lab switch connects with the VLAN switch which afterwards connects on the firewall, the firewall on the ADSL Modem and therefore we have access to the internet. Showing summary a drawing of the connectivity:

                                              END OF REPORT