Networking BasicsArjun Vasanthakumar

Agenda

• Network Definition

• Types of Network

• Network Terms

• OSI Model

• Network Components

• Enterprise Network Architecture

Network Definition

What is Network?

• A network, is a collection of computers and devices interconnected to facilitate communications among users and allows users to share resources.

Types of Network

Local Area Network

• Connects computers and devices in a limited geographical area

Wide Area Network

• LANs that spans over a broad area (regional, global)

Virtual Private Network

• Connects multiple LANs securely over WAN

Network Terms

Common Network Terms (1)

• MAC Address - Physical Address of a Device

▫ E.g. “ 08:00:69:02:01:FC ”

• IP Address – Logical Address of a Device

▫ e.g. “ 192.168.1.254 ”

• Protocol – Set of rules that govern a communication

▫ e.g. TCP, UDP

• Subnet

▫ Block of IP Addresses

Common Network Terms (2)

• Fast Ethernet▫ 10/100 Mbits/sec

• Gigabit Ethernet▫ 10/100/1000 Mbits/sec

• Power Over Ethernet▫ Feature that supports a device to pass power along

with data on Ethernet Cabling

• VLAN▫ a VLAN is a collection of nodes that are virtually

grouped together.

Open Systems Interconnection

(OSI model)

OSI Model

• Open Systems Interconnection ( OSI ) is a standard reference model for communication between two end users in a network. The model is used in developing products and understanding networks.

OSI model - Layers

• Network Process to Application (Email, Internet Explorer)Application

• Data Format, Ensure Data is readable (JPEG, GIF)Presentation

• Establish, Maintain & Disconnect (Host to Host Chat Session)Session

• End to End Connection, Reliability (TCP, UDP)Transport

• Network Address, Best Path (IP, Router)Network

• Access to Media (MAC, Switches, Hub)Data Link

• Binary Transmission (wires, voltages)Physical

Network Components

Passive Components

• UTP Cable

• Fibre Cable

• Patch Panel

• SFP Module

Application

Presentation

Session

Transport

Network

Data Link

Physical

Network Switch

▫ Devices that links nodes in a LAN

▫ Layer 2 Device

▫ Works on MAC Address

Application

Presentation

Session

Transport

Network

Data Link

Physical

Cisco 2960 Switch

Router

▫ Responsible for Routing, Path selection

▫ Layer 3 Device

▫ Works on IP Address

Application

Presentation

Session

Transport

Network

Data Link

Physical

Cisco 1941 Router

Linksys Router

Multi-Layer Switch

▫ Device that switches on OSI layer 2 like an ordinary network switch and provides extra functions on higher OSI layers.

▫ Inter –VLAN Routing

Application

Presentation

Session

Transport

Network

Data Link

PhysicalCisco 3560, Cisco 4500 & Cisco 6500

Wireless Access Point

▫ allows devices to connect to a wired network with out the need of physical cable

Application

Presentation

Session

Transport

Network

Data Link

Physical

Cisco Aironet 1140, 1260, 1500 Series

Firewall

▫ Security Device

▫ Offers protection between Zones

▫ Today's Firewall offers Network to Application Level Protection

Application

Presentation

Session

Transport

Network

Data Link

Physical Cisco ASA

FortiGate UTM

Enterprise Network Architecture

Enterprise NetworkArchitecture

Enterprise NetworkArchitecture

Access SwitchConnects End Users, IP Phones to the LAN .

Enterprise NetworkArchitecture

Core SwitchTies Access switches together. Normally servers and storage devices are connected to this.

Enterprise NetworkArchitecture

Access SwitchIn Small Offices Access Switch tends to take the role of Core Switch.

Enterprise NetworkArchitecture

Network StorageStores Data of Heterogeneous Clients (Servers, PC’s)

Enterprise NetworkArchitecture

RouterAllows to terminate WAN Links. E.g. ADSL, MPLS, Lease Line.

Enterprise NetworkArchitecture

Security ApplianceSecures the Enterprise from internet attacks

Enterprise NetworkArchitecture

Wireless Access PointProvides Wireless Network access to the users.

Enterprise NetworkArchitecture

Unified Communication SystemResponsible for providing IP Telephony, Video Conferencing Services.

Enterprise NetworkArchitecture

Site to Site VPN allows branch offices to share and access corporate resources.

Remote Access VPN allows Remote Users to securely access corporate resources.

3 – Tier Architecture

2 – Tier Architecture (Collapsed Core)

Thank You