Lesson 1: Network Architecture Standard

Network architecture is the design of a communications network. It is a framework for

the specification of a network's physical components and their functional organization and

configuration, its operational principles and procedures, as well as data formats used in its

operation.

Network is a combination of computer hardware, cabling, network devices, and

computer software used together to allow computers to communicate with each other. A

network is basically all of the components (hardware and software) involved in connecting

computers across small and large distances. Networks are used to provide easy access to

information, thus increasing productivity for users.

Network Component play a major role in designing and maintaining network.

Network Components and Terminology

Data are values of qualitative or quantitative variables, belonging to a set of items. Data

in computing (or data processing) are represented in a structure, often tabular

(represented by rows and columns), a tree (a set of nodes with parent-children

relationship) or a graph structure (a set of interconnected nodes).

Node  is a connection point, either a redistribution point or a communication

endpoint (some terminal equipment). The definition of a node depends on the network

and protocol layer referred to.

Client is a piece of computer hardware or software that accesses a service made

available by a server.

Server is a system (software and suitable computer hardware) that responds to requests

across a computer network to provide, or help to provide, a network service. Servers can

be run on a dedicated computer, which is also often referred to as "the server", but many

networked computers are capable of hosting servers. In many cases, a computer can

provide several services and have several servers running.

Peer is a group of functional units in the same layer of a network, by analogy with peer

group.

Network Adapter / Network interface controller (NIC) (also known as a network

interface card, LAN adapter and by similar terms) is a computer hardware component

that connects a computer to a computer network.

Hub is a networking device that allows one to connect multiple PCs to a single network.

Hubs may be based on Ethernet, Firewire, or USB connections.

Switch is a control unit that turns the flow of electricity on or data of in a circuit. It may

also be used to route information patterns in streaming electronic data sent over

networks. In the context of a network, a switch is a computer networking device that

connects network segments.

Router is a device that forwards data packets between computer networks, creating an

overlay internetwork. A router is connected to two or more data lines from different

networks. When a data packet comes in one of the lines, the router reads the address

information in the packet to determine its ultimate destination. Then, using information in

its routing table or routing policy, it directs the packet to the next network on its journey.

Routers perform the "traffic directing" functions on the Internet.

Media / Medium This is how the devices are connected together

Transport protocols occupy layer 4 of the OSI protocol model. The protocols at this

level provide connection-oriented sessions and reliable data delivery services. The

transport layer sits on top of layer 3 networking services.

Bandwidth is a measurement of bit-rate of available or consumed data communication

resources expressed in bits per second or multiples of it (bit/s, kbit/s, Mbit/s, Gbit/s, etc.).

Network Architecture

Most common network architecture types:

Ethernet  is a family of computer networking technologies for local area

networks (LANs). The Ethernet standards comprise several wiring and signaling variants

of the OSI physical layer in use with Ethernet.

FDDI (Fiber Distributed Data Interface) provides a 100 Mbit/s optical standard for data

transmission in local area network that can extend in range up to 200 kilometers

(120 mi).

Token ring local area network (LAN) technology is a protocol which resides at the data

link layer (DLL) of the OSI model. It uses a special three-byte frame called a token that

travels around the ring. Token-possession grants the possessor permission to transmit

on the medium. Token ring frames travel completely around the loop.

Lesson 2: Local Area Network

Local Area Network is a computer network that interconnects computers in a limited area

such as a home, school, computer laboratory, or office building using network media and

the most common form of computer network.

Network Adapter / Network interface controller (NIC) (also known as a network

interface card, LAN adapter and by similar terms) is a computer hardware component

that connects a computer to a computer network.

Wiring / Cabling

Wiring is done for less sophisticated systems and general household gadgets

are connected to electrical line through wiring.

Cabling is done to carry the data in the form of electrical pulses from continents

to continents. The biggest advantage of cabling is that cables are capable of carrying

electrical pulses at lightning speed without incurring any losses during the process.

Hub is a networking device that allows one to connect multiple PCs to a single network.

Hubs may be based on Ethernet, Firewire, or USB connections.

Switch is a control unit that turns the flow of electricity on or data of in a circuit. It may

also be used to route information patterns in streaming electronic data sent over

networks. In the context of a network, a switch is a computer networking device that

connects network segments.

Termination Point is the connection of all physical and there technical access

specifications which form part of the public telecommunications network and are

necessary for access to and efficient communication through that public network.

Wiring cabinet is a small room commonly found in institutional buildings, such as

schools and offices, where data / electrical connections are made. While they are used

for many purposes, their most common use is for computer networking.

Network Adapter / Network interface controller (NIC) (also known as a network

interface card, LAN adapter and by similar terms) is a computer hardware component

that connects a computer to a computer network.

Wiring / Cabling

Wiring is done for less sophisticated systems and general household gadgets

are connected to electrical line through wiring.

Cabling is done to carry the data in the form of electrical pulses from continents

to continents. The biggest advantage of cabling is that cables are capable of carrying

electrical pulses at lightning speed without incurring any losses during the process.

Hub is a networking device that allows one to connect multiple PCs to a single network.

Hubs may be based on Ethernet, Firewire, or USB connections.

Switch is a control unit that turns the flow of electricity on or data of in a circuit. It may

also be used to route information patterns in streaming electronic data sent over

networks. In the context of a network, a switch is a computer networking device that

connects network segments.

Termination Point is the connection of all physical and there technical access

specifications which form part of the public telecommunications network and are

necessary for access to and efficient communication through that public network.

Wiring cabinet is a small room commonly found in institutional buildings, such as

schools and offices, where data / electrical connections are made. While they are used

for many purposes, their most common use is for computer networking.

Wireless Networking Components

Wireless Network Adapter

A wireless network interface controller (WNIC) is a network interface

controller which connects to a radio-based computer network rather than a wire-based

network such as Token Ring or Ethernet. A WNIC, just like other NICs, works on the

Layer 1 and Layer 2 of the OSI Model.

Access Point

A wireless access point (AP) is a device that allows wireless devices to connect

to a wired network using Wi-Fi, or related standards. The AP usually connects to

a router(via a wired network) if it's a standalone device, or is part of a router itself.

Ad Hoc Network

Ad Hoc a Latin phrase "for this", a wireless ad hoc network is a decentralized

type of wireless network.[1] The network is ad hoc because it does not rely on a

preexisting infrastructure, such as routers in wired networks or access points in

managed (infrastructure) wireless networks. Instead, each node participates in routing

by forwarding data for other nodes, so the determination of which nodes forward data is

made dynamically on the basis of network connectivity. In addition to the classic routing,

ad hoc networks can use flooding for forwarding the data.

Infrastructure Network

Infrastructure mode wireless networking bridges (joins) a wireless network to a

wired Ethernet network. Infrastructure mode wireless also supports central connection

points for WLAN clients.

Service Set ID

SSID is a case sensitive, 32 alphanumeric character unique identifier attached to

the header of packets sent over a wireless local-area network (WLAN) that acts as a

password when a mobile device tries to connect to the basic service set. (BSS is a

component of the IEEE 802.11 WLAN architecture.)

Lesson 7: OSI Model

The OSI model defines the generic tasks that are performed for network

communication.

The Open Systems Interconnection (OSI) model (ISO/IEC 7498-1) is a conceptual

model that characterizes and standardizes the internal functions of a communications

system by partitioning it into abstraction layers. The model is a product of the Open

Systems Interconnection project at the International Organization for

Standardization (ISO).

Application (Layer 7)

This layer supports application and end-user processes. Communication partners

are identified, quality of service is identified, user authentication and privacy are

considered, and any constraints on data syntax are identified.

Presentation (Layer 6)

This layer provides independence from differences in data representation

(e.g., encryption) by translating from application to network format, and vice versa. The

presentation layer works to transform data into the form that the application layer can

accept. This layer formats and encrypts data to be sent across a network, providing

freedom from compatibility problems. It is sometimes called the syntax layer.

Session (Layer 5)

This layer establishes, manages and terminates connections

between applications. The session layer sets up, coordinates, and terminates

conversations, exchanges, and dialogues between the applications at each end. It deals

with session and connection coordination.

Transport (Layer 4)

This layer provides transparent transfer of data between end systems, or hosts,

and is responsible for end-to-end error recovery and flow control. It ensures complete

data transfer.

Network (Layer 3)

This layer provides switching and routing technologies, creating logical paths,

known as virtual circuits, for transmitting data from node to node. Routing and forwarding

are functions of this layer, as well as addressing, internetworking, error handling,

congestion control and packet sequencing.

Data Link (Layer 2)

At this layer, data packets are encoded and decoded into bits. It

furnishes transmission protocol knowledge and management and handles errors in the

physical layer, flow control and frame synchronization. The data link layer is divided into

two sub layers: The Media Access Control (MAC) layer and the Logical Link

Control (LLC) layer. The MAC sub layer controls how a computer on the network gains

access to the data and permission to transmit it. The LLC layer controls frame

synchronization, flow control and error checking.

Physical (Layer 1)

This layer conveys the bit stream or electrical impulse, light or radio signal

through the network at the electrical and mechanical level. It provides

the hardware means of sending and receiving data on a carrier, including defining

cables, cards and physical aspects. Fast Ethernet, RS232, and ATM are protocols with

physical layer components.

Server Roles

Server roles – servers can be configured to perform a number of roles. The

applications that the server is running specify the particular server’s role. Servers

typically need services and additional features installed to perform its specific role. When

compared to workstations, servers have more disk space and memory and faster

processors. The server’s role determines the hardware that servers require.

Active Directory Certificate Services

AD CS starting in Windows Server® 2008 provides customizable services for

creating and managing public key certificates used in software security systems that

employ public key technologies.

Active Directory Domain Services

It provides secure hierarchical data storage for objects in a network such as

users, computer, printers and services

Active Directory Federation Services

It provides users with single sign-on access to system and application located

across organizational boundaries. It users a claims based access control authorization

model to maintain application security and implement federated identity.

Active Directory Lightweight Directory Services

It provides flexible support for directory enabled application without the

dependencies that are required for ADDS.

Active Directory Rights Management Services

A form of Information Right Management used on MS WIN the users encryption

and a form of selective functionality denial for limiting access to documents such as

corporate e-mail, word documents, web pages.

Application Server

It provides software application with services such as, data services, transaction

support, load balancing and management of large distributed system.

DHCP Server

A DHCP Server assigns IP addresses to client computers. This is very often

used in enterprise networks to reduce configuration efforts. All IP addresses of all

computers are stored in a database that resides on a server machine.

DNS Server

Domain Name System (DNS) is the name resolution protocol for TCP/IP

networks, such as the Internet. Client computers query a DNS server to resolve

memorable, alphanumeric DNS names to the IP addresses that computers use to

communicate with each other. See more in the DNS Server Overview for Windows

Server 2008.

Fax Server

A fax server is a system installed in a local area network (LAN) server that allows

computer users whose computers are attached to the LAN to send and receive fax

messages.

File Services

Primary purpose of providing a location for shared disk access.

Hyper-V

Codenamed Viridian and formerly known as Windows Server Virtualization

Native hypervisor that enable platform virtualization on x86 - 64.

Network Policy and Access Services

Provides technologies that allow you to deploy virtual private network dial-up net

and 802.11 protected wireless access. It can define and enforce policies for net access

authentication, authorization.

Print and Document Services

Enables you to share printers and scanners on a network, setup prints servers

and scan servers and centralize network printer and scanner management tasks.

Remote Desktop Services

Allows a user to access applications and data on a remote computer over a

network using the Remote Desktop Protocol (RDP).

Web Server (IIS)

Web Server (Internet Information Services) a wed server applications and se tof

feature extension modules created by Microsoft for use with Microsoft Windows.

Windows Deployment Services

A technology from Microsoft for network-based installation of Windows Operating

System successor to Remote Installation Services.

Windows Server Update Services

Previously known as Software Update Service (SUS)

computer program developed by Microsoft Corporation that enables administrators to

manage the distribution of update and hotfixes released for Microsoft products to

computers in a corporate environment.