WIRELESS TECHNOLOGY

WIRELESS TECHNOLOGY is generally used for mobile IT equipment. It encompasses cellular telephones, personal digital assistants (PDA's), and wireless networking.

Other examples of wireless technology include GPS units, garage door openers and or garage doors, wireless computer mice and keyboards, satellite television and cordless telephones.

What is Wireless?

Wireless networking technologies range from global voice and data networks which allow users networks, to establish wireless connections across long distances, to infrared light and radio frequency technologies that are optimized for short‐range wireless connections.

Wireless network most commonly use to refer to a telecommunications network whose interconnections between nodes is implemented without the use of wires, such as a computer network.

Wireless telecommunications networks are generally implemented with some type of information transmission system that uses electromagnetic waves, such as radio waves, for the carrier

Wireless communication involves

•        radio frequency communication

•        microwave communication, for example long‐range line of sight via highly directional antennas or short line‐of‐antennas, shortrange communication

•        infrared (IR) short‐range communication, for example from remote controls or via IRDA Applications may involve point‐to‐point communication, point‐to‐multipoint communication, broadcasting , cellular networks and other wireless networks.

Devices commonly use wireless networking technologies:

•         portable computers,

•         desktop computers

•         hand‐held computers,

•         personal digital assistants (PDAs),

•         cellular phones,

•         pen‐based computers,

•         pagers, GPS etc.

The practical purposes

•         mobile users can use their cellular phone to access e‐mail.

•         Travelers with portable computers can connect to the Internet through base stations installed in airports, railway stations, and other public locations.

•         At home, users can connect devices on their desktop to synchronize data and transfer files.

Type of Wireless Network

1.       Wireless wide area networks (WWANs)

2.       Wireless metropolitan area networks (WMANs)

3.       Wireless local area networks (WLANs)

4.       Wireless personal area networks (WPANs)

1.            Wireless wide area networks (WWANs)

WWAN technologies enable users to establish wireless connections over remote public or private networks. These connections can be maintained over large geographical areas, such as cities or countries, through the use of multiple antenna sites or satellite systems maintained by wireless service providers.

for more information..

2.            Wireless metropolitan area networks (WMANs)

WMAN technologies enable users to establish wireless connections between multiple locations within a metropolitan area (for example, between multiple office buildings in a city or on a university campus), without the high cost of laying fiber or copper cabling and leasing lines

for more information...

3.            Wireless local area networks (WLANs)

Wireless Local Area Networks (WLAN) are implemented as an extension to wired LANs within a building and can provide the final few meters of connectivity between a wired network and the mobile user.

WLAN technologies enable users to establish wireless connections within a local area (for example, within a corporate or campus building, or in a public space, such as an airport). WLANs can be used in temporary offices or other spaces where the installation of extensive cabling would be prohibitive, or to supplement an existing LAN so that users can work at different locations within a building at different times.

4.                   4      .Wireless personal area networks (WPANs)

WPAN technologies enable users to establish ad hoc, wireless communications for devices (such as PDAs, cellular phones, or laptops) that are used within a personal operating space (POS).

A POS is the space surrounding a person, up to a distance of 10 meters.

Application

•        Voice and messaging,

•        Hand‐held and other Internet‐enableddevices, and

•        Data Networking.

Voice and messaging,

•        Cell phones, pagers.

•        analog or digital standards

–        The analog standard is the Advanced Mobile Phone Service (AMPS).

–        Digital standards are Global System for Mobile Communications (GSM), Time Division Multiple Access (TDMA), or Code Division Multiple Access (CDMA).

Hand‐held and other Internet‐enabled devices

•        Internet‐enabled cell phones and Personal Digital Assistants (PDAs) can connect to the Internet across a digital wireless network.

•        Uses Wireless Application Protocol (WAP),and WML (Wireless Markup Language)

•        the majority of current Internet content is not optimized for these devices; presently, only email, stock quotes, news, messages and simple transaction oriented services are messages, transaction‐available.

•        Other limitations include low bandwidth (less than 14 Kbps), low quality of service, high cost, the need for additional equipment, and high utilization of devices' battery power. Nevertheless, this type of wireless technology is growing rapidly with better and more interoperable products.

Data Networking.

•        Infra Red

•        wireless local area networks (WLANs)

•        broadband wireless.

•        Bluetooth,

•        WiMax

حافظ إبرهيم : الفصل الأول : التعريف بالأديب / الشاعر

المبحث الأول : نشأته ودراسته

       ولد محمد حافظ إبرهيم في ديروط من أعمال مديرية أسيوط حوالي سنة 1870 إذ كان أبوه إبرهيم فهمي من المهندسين على بناء قناطرها. ولما كان عمره سنتين توفي أبوه فقيراً في ديروط  فانتقلت به أمه إلى القاهرة فكفله خاله وأدخله (المدرسة الخيرية) فمدرسة المبتديان فالمدرسة الخديوية. ثم انتقل خاله إلى طنطا فنقله معه. فقضى فيها بضع سنين متبطلا يزجي فرغه بالقراءة، ويدفع ملاله بالقيض. حوالى سنة 1872. كانت سفينة (ذهبية) ترسو على شاطئ النيل.

الباب الأول : تعريف إيجاز

الفصل الأول

تعريف الإيجار ، لغة واصطلاحا:

التعريف : الإيجار لغة : اختصار الكلام وتقليل ألفاظه مع بلاغته ، يقال لغة : أوج ز الكلام إذا جعله قصيراينتهي من نطقه من نطقه بسرعة.

ويقال : كلام وجير ، أي : خفيف قصيرا. أوجز في صلاته إذا خففها ولم يطل فيها.

الإيجاز وأنواعها في القرآن و الحديث النبوي والشاعر

مقدمة

بسم الله الرحمن الرحيم

لما كانت البلاغة هي مطابقة الكلام لمقتضى الحال  أبتدأ كلامي بالحمد لله الذي شهدت له بالألوهية جميع مصنوعاته وأقرت له بالعبودية جميع مخلوقاته ثم الصلاة والسلام على أفضل الخلق كلهم المبعوث رحمة للعالمين ومستهلا كلامي بالتنويه على أقسام علم البلاغة وهي:-

SAHABAT

Assalamualaikum w.b.t..

Sahabat...

disini aku ingin bercerita bersamamu...

mungkin dari dalam sanubariku ini...
ingin aku bercerita padamu dahulu..
tapi terdapat kekangan masa dan hal2 tertentu...

Sahabat..

aku telah anggap engkau umpama keluargaku

engkau juga merupakan salah seorang idolaku, role model bagiku...

akhalkmu, perbuatanmu, pertuturanmu, perwatakanmu dll...

Sahabat..

aku berasa sangat untung bertemu denganmu...

disitu aku dapat pelajari pelbagai darimu

mungkin secara langsung dan mungkin juga secara tidak langsung

ia sungguh bermakna bagiku..

Sahabat...

jadikanlah persahabatan yang telah kita bina ini

persahabatan yang diredhai oleh-Nya

persahabatan di dunia dan akhirat

Sahabat...

aku juga  merupakan insan yang lemah

dan memerlukan sokongan dan dorongan dari mu

Sahabat...

jika aku ada buat kesilapan, kesalahan

bimbinglah, tegurlah, nasihatlah sahabatmu ini...

walaupun ia agak sukar bagi mu

mungkin aku tidak sedar...

Sahabat...

mungkin suatu hari nanti aku akan pergi menemui-Nya dahulu

jadi doakanlah moga aku tenang disana nanti...

dan aku yakin kita semua akan laluinya..

mgkin awal dan mgkin lambat sedikit..

Sahabat...

dalam hidup ini..

inginku lakukan perkara yang disenangi oleh kalian..

mungkin susah bagiku untuk lakukan begitu...

namun akan ku cuba sedaya upaya ku...

Sahabat...

disini juga ingin aku memperingati diriku ini dan juga diri sahabatku...

kita mesti ingat, kita adalah hambaNya, kita juga seorang anak, kita juga seorang khalifah..

jadi agak banyak tanggungjawab yang perlu kita pikul selagi mana kita digelar sebagai manusia..

maka kita kenalah jaga bersama2 tanggungjawab itu..

Sahabat..

Hatiku sungguh gembira apabila melihat mu gembira

hatiku tidak akan tenteram apabila melihat mu dalam kesusahan..

kalau ada masalah, kongsilah bersama jika mu perlukan..

InsyaAllah... jika aku mampu, aku akan cuba bantu mu sedaya upaya ku ini..

Sahabat...

Akhir kalam, aku doakan semoga kita semua :-

memperolehi rahmat dan keredhaan Allah di dunia mahupun diakhirat..

kekal dalam persabahatan ini walaupun pelbagai dugaan akan ditempuhi kelak..

bahagia di sisi keluarga, masyarakat dan sekalian makhluk

Sahabat... Anda adalah terbaik bagiku...

Wasalam...

Protocol and Cabling

LOCAL AREA NETWORK (LAN) TECHNOLOGY

·         10/100/1000 Mbps Ethernet

·         100 Mbps FDDI

·         155/620 Mbps ATM

·         4/10/45 Mbps Wireless

What is a Protocol?

•        A protocol is a set of rules that governs the communications between computers on a network.

•        These rules include guidelines that regulate the following characteristics of a network:

1.       access method,

2.       allowed physical topologies,

3.       types of cabling, and

4.       speed of data transfer.

Protocol

•        Protocol (communications protocol)= standards that specifically address how the devices on a network communicate, i.e

1.       How the data is packaged for transmission

2.       How receiving devices acknowledge signals from sending devices

3.       How errors are detected and handled

Protocol

Logical topologies are bound to network protocols and describe how data is moved across the network.

•        Ethernet, LocalTalk,Token ring for wired networks

•        TCP/IP and WAP for internet

•        WiFi for wireless networks

•        Bluetooth, for short range wireless network

Protocol : Ethernet

•        the most widely used wired networks protocol

•        Early Ethernet network were half duplex, uses an access method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) a system where LAN Technology Detection), each computer listens to the cable before sending anything through the network to avoid collisions.

•        Since 1997 Ethernet uses full duplex communication, that does not require listening to other messages and no collisions occur.

•        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.

•        Early Ethernet protocols (10BASE-T) support 10BASE transmissions rate 10 Mbps

•        Today

1.       100BASE-T or 100BASE-TX – 1000Mbps (1Gbps

2.       10Gigagbit Ethernet – 10Gbps

Protocol : Localtalk

•        a network protocol that was developed Macintosh computers.

•        used a method called CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance), where a computer signals its intent to transmit before it actually does so.

•        allows for linear bus, star, or tree topologies using twisted pair cable.

•        disadvantage : slow speed (only 230 Kbps).

Protocol : Token Ring

•        developed by IBM in the mid-1980s.

•        access method involves token-passing.

•        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- the data is captured by the receiving computer

CABLING

•        Cable is the medium through which information usually moves from one network device to another .

•        several types of cable are commonly used with LANs.

•        In some cases, a network will utilize only one type of cable, other networks will use a variety of cable types

Types of Cables

1.       Unshielded Twisted Pair (UTP) Cable

2.       Shielded Twisted Pair (STP) Cable

3.       Coaxial Cable

4.       Fiber Optic Cable

1.            Unshielded Twisted Pair (UTP) Cable

The cable has four pairs of wires inside the jacket. Each pair is twisted with a different number of twists per inch to help eliminate interference from adjacent pairs and other electrical devices.

The standard connector for unshielded twisted pair cabling is an RJ-45 connector

A disadvantage of UTP is that it may be susceptible to radio and electrical frequency interference.

1.                   Shielded Twisted Pair (STP) Cable

STP is a type of cable consists of two individual wires wrapped in a foil shielding to help provide a more reliable data communication.

•        suitable for environments with electrical interference;

•        however, the extra shielding can make the cables quite bulky.

•        often used on networks using Token Ring topology.

2.                   Coaxial Cable

Coaxial cabling has a single copper conductor at its center.

A plastic layer provides insulation between the center conductor and a braided metal shield

The metal shield helps to block any outside interference from fluorescent lights, motors, and other computers.

more informations

Coaxial Cable Connectors

• The most common type of connector used with coaxial cables is the BayonetllCl ( C) Neill-Concelman BNC) connector

• Different types of adapters are available for BNC connectors, including a Tconnector, barrel connector, and terminator.

4.            Fiber Optic Cable

• consists of a center glass core surrounded by several layers of protective materials

• It transmits light rather than electronic signals eliminating the problem of electrical interference.

• ideal for certain environments that contain a large amount of electrical interference..

• able to transmit signals over much longer distances than coaxial and twisted pair.

NETWORK OPERATING SYSTEM (NOS)

•        Software that controls a network and its message (e.g. packet) traffic and queues, controls access by multiple users to network resources such as files, and provides for certain administrative functions, including security. coordinate the activities of multiple computers

•        across a network.

•        acts as a director to keep the network running smoothly.

•        A NOS is not the same as the networking tools provided by some existing OSs, Windows XP for instance.

•        An NOS is an OS that has been specifically written to keep networks running at optimal performance.

•        Some popular NOSs include:

•        Windows NT , IBM AIX, Sun Solaris, Windows 2000 Server, Windows Server 2003,Inferno Novell NetWare, Red Hat Linux, BSD

•        The two major types of network operating systems are: :

1.       Peer to Peer

2.       Peer-to-– Client/Server

1.            Peer to Peer

·         In a peer-to-peer network, all computers are considered equal; they all have the same abilities to use the resources available on the network

•        allow users to share resources and files located on their computers and to access shared resources found on other computers.

•        do not have a file server or a centralized management source

•        designed primarily for small to medium local area networks.

•        AppleShare and Windows for Workgroups are examples of programs that can function as peerto- peer network operating systems.

Advantages

•        Less initial expense - No need for a dedicated server.

•        Setup - An operating system such asWindows XP/…) already in place may onlyneed to be reconfigured for peer-to-peer operations.

Disadvantages

•        Decentralized - No central repository for files and applications.

•        Security - Does not provide the security available on a client/server network.

2.            Peer-to-– Client/Server

allow the network to centralize functions and applications in one or more dedicated file servers

•        the file servers become the heart of the system, providing access to resources and providing security.

•        individual workstations (clients) have access to the resources available on the file servers.

•        Novell Netware and Windows 2000 Server are examples of client/server network operating systems.

more information

10 Wasiat Imam Hassan Al-Banna

Dengan Nama Allah Yang Maha Pemurah Lagi Maha Penyayang

   1)        WAHAI SAUDARAKU,

   Segeralah tunaikan solat di awal waktu. Dikala mendengar azan.

Usahakanlah semampu terdaya. Ini membuktikan kesungguhan anda. Di

situ ada sumber kejayaan. Di situ ada sumber pertolongan. Di situ

ada sumber taufiq. Perhatikanlah banyak perintah ayat al-Quran.

...dimulakan dengan menyebut solat di awalnya. Perhatikanlah Tuhan

mensyariatkan solat... Juga di medan perang. Walaupun... Di saat

genting dan cemas.

   2)        WAHAI SAUDARAKU,

  Bacalah al-Quran dan cuba memerhati mesejnya. Selalulah berzikir

dan cari ilmu walaupun sedikit. Kurangilah dengan masa yang tidak

bertujuan. Sesungguhnya al-Quran adalah sumber asli lautan ilmu.

Sumber hidayah kepada anda dan saya. Bacalah al-Quran, kelak ia

memberi syafaat. sentiasalah membaca, menghafal dan.. cuba hayati

mesej arahannya. Selalu berzikir, berzikir dan terus berzikir!!! Di

sini ada ketenteraman Di sini ada kedamaian. Di sini ada kesalaman

Jadilah hamba yang sejahtera.

   3)        WAHAI SAUDARAKU,

   Dorongkanlah diri untuk menguasai Bahasa al-Quran. Mulakan dulu

walaupun sepatah perkataan. Sebenarnya anda telah lama bermula,

Iaitu sejak anda solat setiap hari. Sebut dulu walaupun tak faham.

Antara mala petaka pertama menimpa umat kita... Ialah kecuaian

menguasai bahasa agamanya. Juga mengutamakan bahasa pasar, Ayuh!!!

Apa tunggu lagi?????? Bukalah ruang walaupun seminit!!!

   4)        WAHAI SAUDARAKU,

   Usahlah bertarung idea tanpa adabnya!!! Berdebatlah jika kiranya

berbuahkan kebaikan. Awasilah pertengkaran, Kerana di sana ada

unsur lain membisikkan? Syaitannnn namanya!!!

   5)    WAHAI SAUDARAKU,

   Senyumlah selalu tapi bersederhanalah dalam ketawa!!!

   Rasulullah saw adalah yang paling banyak senyum. Beliau ketawa

kena pada tempatnya. Tapi berpada-pada sahaja, wahai kawan! Plato

juga berharap agar pementasan hiburan... Yang tidak bermutu terlalu

banyak ketawa bodoh. Hanyalah disaksikan oleh golongan abdi. Dan

orang upahan asing! Begitu juga Aristotle berpendapat Supaya

golongan belia ditegah daripada menyaksikan hiburan-hiburan yang

membolehkan perbuatan ketawa berlebih-lebihan. supaya tidak

menular. Keburukan dalam diri!!!

   6)        WAHAI SAUDARAKU,

   Seriuslah selalu dan berguraulah berpatutan. Tanpa serius,

hilanglah kesungguhan!!! Tanpa bergurau, tawarlah kehidupan. Kata

seorang penyair: Berikan kerehatan pada jiwamu. Yang sibuk dengan

berfikir. Ubati dengan bergurau. Tapi, Kalau mengubatinya dengan

bergurau. Mestilah dalam batas. Seperti kau masukkan garam ke dalam

gulai.

   7)        WAHAI SAUDARAKU,

   Kawallah nada suaramu. Setakat yang diperlukan oleh pendengar di

depanmu. Janganlah jadi seperti orang bodoh. Bahkan menyakit hati

orang lain pula!!! Luqman El-Hakim juga mencela orang yang tidak

pandai menjaga nada suara pada tempatnya. Itulah katanya suara

keledai!!! Surah al-Isra' memberi tip kepada kita... Jangan

keraskan suramu dalam solat Tapi jangan pula merendahkannya.

Carilah jalan tengah di antara keduanya.

   8)        WAHAI SAUDARAKU,

   Usahlah umpat mengumpat. Usahlah merendah-rendahkan pertubuhan

lain. Bercakaplah jika ada unsur kebajikan. Ayuh!!!

Hindarilah...mengumpat! Tidak sekali mencabuli jemaah-jemaah

lain!!! Perkatakanlah kebaikan demi kebajikan bersama. Sukakah anda

memakan daging pasti anda suka!! Tapi sukakah anda memakan daging

kawan anda yang telah mati?? Sekali-kali tidak!!! Begitulah dosa

orang yang mengumpat. Bertaubatlah jika anda mengumpat Tapi mesti

minta ampun terhadap orang umpatanmu bersama!!! Boleh

mengumpat...apabila ada tujuan syarie. -untuk menuntut keadilan

apabila dizalimi -untuk menghapuskan kemungkaran -kerana memberi

amaran kepada Muslim tentang kejahatan -kerana mengisytiharkan

kefasikan dan kejahatan.

  

 9)        WAHAI SAUDARAKU,

  

    Luaskanlah interaksimu dengan umat manusia Sekalipun mereka

tidak diminta berbuat demikian!!! Salam kasih sayang adalah untuk

semua. Salam kemesraan adalah untuk sejagat. Hulurkanlah,

hulurkanlah salam perkenalan...! Lihatlah pensyariatan ibadah haji.

Pelbagai bangsa datang berkunjung!!! Pelbagai lapisan datang

berkunjung!!! Pelbagai darjat datang berkunjung!!! Sama-sama

menjunjung obor suci. Tidak mengenali tapi tak sepi.

  

 

10)       WAHAI SAUDARAKU,

  

     Maksimumkanlah faedah waktu anda dan Tolonglah orang lain supaya

manfaatkan masa. Hadkanlah masa penunaiannya. Biasakan hidup

berjadual di hadapan. Bijaksanakanlah menggunakan waktu anda!

Bersegeralah, kerana... Sabda Nabi saw bermaksud: "Bertindak

segeralah melakukan amal..." (Diulang 7 kali..) Sayanglah masa

saudaramu!!! Hormatilah waktu mereka!!! Usahlah berbicara meleret-leret... Tanpa haluan dan noktahnya. 

Bos dan Pemimpin

Bos kerah pekerja

Pemimpin galakkan mereka

Bos memegang kuasa

Pemimpin bergantung kepada budi

Bos menimbulkan ketakutan

Pemimpin memancarkan kesayangan

Bos kata ‘’AKU’’

Pemimpin kata ‘’KITA’’

Bos menunjuk siapa salah

Pemimpin menunjuk apa yang salah

Bos tahu kaedah teori

Pemimpin tahu praktikalnya

Bos memaksa dihormati

Pemimpin sentiasa dihormati

Jadilah Pemimpin jangan jadi Bos

*pilihan di tangan anda..... (^__^)

p/s : Persatuan Pelajar SMA Al-Khairiah

Network Topology

Network topology is the study of the arrangement or mapping of the elements (links, nodes, etc.) of a network, especially the physical (real) and logical (virtual) interconnections between nodes

PHYSICAL TOPOLOGY :

The physical layout of devices on a network. or the way that the devices on a network are arranged and how they communicate with each other The way that the workstations are connected to the network through the actual cables that transmit data - the physical structure of the network

LOGICAL TOPOLOGY :

the mapping of the flow of data between the nodes in the network determines the logical topology of the network the way that the signals act on the network media, or the way that the data passes through the network from one device to the next without regard to the physical interconnection of the devices.

Types/Classification of physical topologies

1.  Linear Bus
2. Star
3. Star-Wired Ring
4. Tree
5.  FDDI
6. Mesh

LINEAR BUS

• A linear bus topology consists of a main run of cable with a terminator at each end.  All nodes (file server, workstations, and peripherals) are connected to the linear cable.
• Ethernet and LocalTalk networks use a linear bus topology.
• The bus cable carries the transmitted message along the cable. As the message arrives at each workstation, the workstation computer checks the destination address contained in the message to see if it matches it's own. If the address does not match, the workstation does nothing more.
• If the workstation address matches that contained in the message, the workstation processes the message. The message is transmitted along the cable and is visible to all computers connected to that cable.

Advantages	Disadvantages
Easy to install	Out-of-date technology
Costs are usually low	If cable breaks, whole network is down
Easy to add systems to network	Can be difficult to troubleshoot
Great for small networks	Unmanageable in a large network

RING

• Each of the systems is connected to its respective neighbor forming a ring.
• The main difference between the bus and ring is that the ring topology does not require termination. Because the systems are connected all together in a loop, there is no beginning and end point as there is with the bus topology.
• This configuration is seen in Fiber Distributed Data Interface (FDDI) networks.

STAR

•  A star topology is designed with each node (fileserver, workstations, and peripherals) connected directly to a central network hub or concentrator
• Data on a star network passes through the hub or concentrator before continuing to its destination.
• The hub or concentrator manages and controls allbfunctions of the network. It also acts as a repeater for the data flow.
• This configuration is common with twisted pair cable; however, it can also be used with  coaxial cable or fiber optic cable.
• The protocols used with star configurations are usually Ethernet or LocalTalk

Advantages

• Easy to install, and wire.
•  Easy to add new workstations
• No disruptions to the network when connecting or removing devices.
• Any non-centralised failure will have very little effect on the network
•  Easy to detect faults and to remove parts.
• Centralized control
• Centralized network/hub monitoring

Disadvantages

• Requires more cable length than a linear topology.
• If the hub or concentrator fails, nodes attached are disabled.
•  More expensive than linear bus topologies because of the cost of the concentrators.

STAR WIRED

•  A star-wired topology may appear (externally) to be the same as a star topology.
•  Internally, the MAU (multistation access unit) of a star-wired ring contains wiring that allows
• information to pass from one device to another in a circle or ring
• The Token Ring protocol uses a star-wired topology.

TREE

•  A tree (hybrid) topology combines characteristics of linear bus and star topologies.
• It consists of groups of star-configured workstations connected to a linear bus backbone cable. Tree topologies allow for the expansion of an existing network, and enable schools to configure a network to meet their needs.

Advantage

• Point-to-point wiring individual segments

Disadvantages

•  Overall length of each segment is limited by the type of cabling used.
• If the backbone line breaks, the entire segment goes down.
• More difficult to configure and wire than other topologies.

FDDI (Fiber Distributed Data Interface)

• 100mbps
• Normally implemented over fiber optic (fast- Ethernet, UTP)
•  Dual redundancy built in by use of primary and secondary ring
• Automatic bypassing and isolation of fault nodes

Reference : Note (Topology)