advance concepts of networking

8/12/2019 Advance Concepts of Networking

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Copyright | HP Education2

Computer Network

Interconnection of two or more computers and peripherals

Allows user to share and transfer information


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Types of Computer Networks

ComputerNetworks

Local

Area Network(LAN)

Campus

Area Network(CAN)

Metropolitan

Area Network(MAN)

Wide

Area Network(WAN)

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Networks are classified depending on the geographical area covered by thenetwork


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Copyright | HP Education4 4

Local Area Network (LAN) - I

Covers a small area Connects computers and workstations covering a local area like, office or home


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Types of LAN

LANTypes

Ethernet

Token

Ring Token Bus FDDI

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LANs are classified depending on the techniques used for data sharing


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Campus Area Network (CAN)

Made up of multiple LANs within limited area Connects different LANs in a campus


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Interconnects networks within a city Supports data and voice transmission

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Metropolitan Area Network


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Covers a wide geographical area which includes multiple computers or LANs e.g.

Internet

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Wide Area Network


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Client/Server Configuration

Consists of two elements, Client and Server Server:

A centralized element which provides resources to client

Manages data, printers or network traffic

Client:

Manages local resources used by users such as monitor, keyboard, CPU andperipherals


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Open System Interconnection (OSI) Model - II


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Topologies

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Introducing Topologies

Topology refers to physical or logical arrangement of network Physical topologies are

Single Node

Bus

Star

Ring Mesh

Tree

Hybrid

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Single device, at times device called dumb terminal is connected to the server

Devices operates on files from server and returns them back after completing task

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Single Node Topology - I


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Disadvantages:

Network consists of single device

Dumb terminal is dependent onserver

Advantages:

Easy to install, configure andmanage

Least expensive

Single cable is required

Single Node Topology - II


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Bus topology - I

All devices are connected to a common cable called trunk Maximum segment length of cable is 200 m

Maximum of 30 devices per segment


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Bus topology - II

Server is at one end and devices are at different positions 50 ohm terminator is used

Devices are not responsible for data transmission

Number of collisions are more

Usually uses Thinnet or Thicknet

Performance degrades as more computers are added to the bus.


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Bus topology - III

Advantages:

Installation of devices is easy

Requires less cable compared to

star topology

Less expensive and works better forsmaller networks

Disadvantages:

If backbone breaks, entire networkgets down

Difficult to isolate problems

Limited number of devices


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Star Topology - I

Each device is connected to a central device called hub through cable Data passes through hub before reaching destination

If a computer goes down, the network functions normally.

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Star Topology - II

Advantages:

Easy to install, configure, manageand expand

Centralized management

Addition or removal of device doesnot affect the whole network

Disadvantages:

Requires more cable

Failure of hub affects entire

network More Expensive

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Ring Topology - I

Devices are connected in a closed loop

All devices have equal access to media

Most common type is Token Ring

Each computer acts as a repeater andkeeps the signal strong

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Ring Topology - II

Advantages:

Data travels at greater speed

No collisions

Handles large volume of traffic

Disadvantages:

More cabling is required comparedto bus

One faulty device affects the entirenetwork

Addition of devices affect network

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Dual Ring Topology

Consists of two independent primary

and secondary rings

Secondary ring is redundant, used only

when primary stops functioning

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Mesh Topology - I

Used in WANs to interconnect LANs

Every device is connected to every

other device

Use routers to determine the best path

of communication

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Mesh Topology - II

Full mesh topologyAll devices are connected to each other

Partial mesh topology - Some devices are connected to only those with whom they

exchange most of the data

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Types

Full mesh Partial mesh


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Mesh Topology - III

Advantages:

Improves fault tolerance

Failure of one link doesnot affect entire network

Centralized

management is notrequired

Disadvantages:

Difficult to install and

manage

Each link from one

device to other requires

individual NIC

Very much expensive

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Hybrid Topology - I

Combines two or more different physical topologies

Commonly Star-Bus or Star-Ring

Star-Ring uses Multistation Access Unit (MAU)

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Hybrid Topology - II

Advantages:

Used for creating largernetworks

Handles large volume oftraffic

Fault detection is easy

Disadvantages:

Installation andconfiguration is difficult

More expensive thanother topologies

More cabling is required

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Transmission Media


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Segment Length Length of single wire Attenuation Indicates loss of signal

Bandwidth Amount of data carried by cable

Number of Segments Maximum number of

segments in network Cost Copper cables are cheapest, fiber optic cables

are expensive

Interference susceptibility and crosstalk Defines

concept of electronic interference on cables

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Characteristics of Cables


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Types of cables

Copper medium is the cheapest mode of data transfer

Types of cables

Coaxial cable Twisted pair cables

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Consist of a solid copper core surrounded by an insulator mainly made up of Poly

Vinyl Chloride (PVC) or Teflon Coaxial cables are less prone to interference (both internal and external)

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Coaxial cable


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Types of Coaxial cable

Coaxial cables are mainly divided into four categories

Types ofCoaxial cables

RG58 RG8 RG6 RG59

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Maximum segment length is 200 (185) meters

Interference protection is better than twisted pair cables

BNC-T connector is used to connect this cable

Used in thinnet (10BASE2) network

Mostly used in changing environments

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RG58


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Maximum segment length is 500 meters

Interference protection is good compared to any copper cable

BNC-T or Vampire Tap connector is used to connect this cable

Used in 10BASE5 network

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RG8


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RG6

Broadband quad-shielded cable

Provides lower attenuation characteristics

Useful in cable TV, CCTV and satellite dish

antenna

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RG59

Solid conductor is surrounded by afoam polyethylene dielectric

Useful in security camera, cable TV and

home theatre

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Twisted Pair Cables

A pair of cables twisted around each other forms a twisted pair cable.

Twisted Pair cables

UnshieldedTwisted Pair

ShieldedTwisted pair

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UTP

Cat1

Cat2

Cat3

Cat4Cat5

Cat5e

Cat6

Cat7

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UTP Cable Types


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STP Cables

Pair of wires wound around each otheris placed inside shield

Better protection from EMI, RFI and

crosstalk as compared to UTP

Maximum segment length of 100

meters

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Consists of centre glass core surrounded by cladding

Electrical signals are converted into light signals

LED or laser is used to transmit signal

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Fiber Optic Medium


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BandwidthCarries large amount of data ranging from 100 Mbps to 1 Gbps Segment LengthTransmits data signals over larger distance

InterferenceNo electric signals pass through these types of cables thus providing

security

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Fiber Optic Cable Characteristics

Fib O ti C bl T


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Fiber Optic Cable Types

Fiber optic cables can carry signals in a single direction.

Fiber Optic Cable

Types

Single Mode Multi mode

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A type of cable that has only a single strand of glass fiber with a thin diameter.

Fiber optic cables that use lasers are known as single mode cable.

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Single Mode Fiber Optic cable

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A type of cable that contains a glass fiber with a larger diameter. It is a 62.5/125 micrometer fiber cable.

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Multi Mode Fiber Optic cable


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M di C i


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Copyright | HP Education

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Media Comparison

Characteristics UTP STP Coaxial Cables Fiber Optic Cables

Bandwidth 10 Mbps 100

Mbps

10 Mbps 100

Mbps

10 Mbps 100 Mbps - 1 Gbps

Maximum cable

segment

100 meters 100 meters 200500 meters 2 k.m.100 k.m.

Interference rating Poor Better than UTP Better than twistedpair wires

Very good ascompared to

any other cable

Installation cost Cheap Costly than UTP Costly than twisted

pair wires

Most costly to

install

Bend radius 360 degrees / feet 360 degrees / feet 360 degrees / feet or

30 degrees /

feet

30 degrees / feet

Security Low Low Low High

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I t d i N t k El t


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Introducing Network Elements

Networking devices interconnects networks

Manage data flow and network traffic

Networking

Devices

Repeaters Hubs Bridges Switches Routers GatewaysOther

Devices

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Repeaters


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Operate at Physical Layer of the OSI model

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Repeaters

Reshape the weak signal

Connect two segments of the same LAN

Hubs I


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Hubs - I

Simplest and low cost device Also known as Multi-port Repeater

Operate at Physical Layer like Repeater

Data transfer to all the ports

Hub types:

Active hub Provides signal regeneration

Passive hub No signal regeneration

Intelligent hub Provides management of each port

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Operation of Hub

Bridges I


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Bridges - I

Layer 2 devicesas works at Data

Link Layer of the

OSI model

Interconnectmultiple LANs

and manages

data flow

Bridges II


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Bridges - II

Working of a bridge

Bridges III


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Bridges - III

Capable of passing a frame

Check Physical address

Pass frame to the specified segment

Perform error checking on the frame

Bridges

TransparentBridge

TranslationalBridge

Source-routeBridge

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Bridges IV


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Features Easy to use as just plug in device Helps in network expansion

Divides large network into small segments

Used for increasing network reliability

Disadvantages

Frames are buffered so provides network delay

During high traffic may overload network

Does not filter broadcast packets

Expensive than Repeaters

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Bridges - IV

Switches


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Switches

SwitchingMethods

Cut-throughMethod

Store &ForwardMethod

Fragment-FreeMethod

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Provide signal flow management

Replace slower hub

Being a Data Link Layer device uses MAC address

for data transfer

Data transfer to specific port

Routers - I


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Routers - I

Operate at Network Layer of the OSI model

Can connect nearer or far network segments

Routers II


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Routers - II

Decide the best route with the help of network layeraddress

Responsible for Source to Destination delivery of

packet

Route types: Static route Routing tables are manually configured

Dynamic route Routing tables are automatically

configured

Routing Protocols - I


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Routing Protocols - I

Helps routers to learn network topology and

network changes

Routing algorithms are used by routing protocols for

deciding the path

Gateways - I


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Gateways - I

Gateway

Types

Address

Gateway

Protocol

Gateway

Application

Gateway

Transport

Gateway

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Operate at all layers of the OSI model Act as gate to other networks

A default gateway is on the same subnet as your

computer

Gateways - II


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Gateways - II

Address Gateway Interconnects same protocol

networks

Protocol Gateway Interconnects different protocol

networks Application Gateway Connects two parts of

applications

Transport Gateway Connects networks at

transport layer

Other Devices - I


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Other Devices - I

OtherDevices

Multi-Protocol

RoutersBrouters

Layer 3

Switches

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Multi-protocol router supports multiplecommunication protocols

Like router, it operates at Network Layer

Other Devices - II


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Other Devices II

Brouter provides combined functions of Bridge and

Router

Works at two layers, Data Link and Network

Can operate only as bridge or only as router

High performance switch operating at network layeris Layer 3 Switch


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Network Protocols

Introducing Protocols


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Set of predefined rules used by devices in network for data transfer

Network Protocols:

TCP/IP

ARP/RARP

ICMP/IGMP

UDP IPX/SPX

HDLC/SDLC

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Introducing Protocols

TCP/IP


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Two layer communication protocol used by Internet TCP provides connection-oriented reliable transport service Divides the message into smaller packets called segments IP is a connectionless and unreliable datagram protocol and provides no error

checking IP transfers data in the form of packets called datagrams

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TCP/IP

TCP/IP Protocol Suite


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TCP/IP Protocol Suite

Designed before OSI model

Consists of five layers

Provides independent protocols at

each layer

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ARP/RARP


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To deliver packet both physical and logical addresses are necessary

Address Resolution Protocol (ARP) provides physical address when logical address isknown

Reverse Address Resolution Protocol (RARP) maps logical address to physical address

RARP is useful when device is booted for first time

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ARP/RARP

ICMP/IGMP


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Internet Control Message Protocol (ICMP) provides error reporting and query

management mechanism ICMP handles problems occurring while packet transmission

Internet Group Message Protocol (IGMP) manages multicasting and group

membership of devices

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ICMP/IGMP


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IPX/SPX


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Novell NetWare system uses IPX/SPX as communication protocol within networks IPX (Internetwork Packet Exchange) operates at Network layer for connectionless

communication

SPX (Sequenced Packet Exchange) operates at Transport layer for connection-

oriented communication

Together, IPX/SPX provides same services as TCP/IP

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IPX/SPX

IPX/SPX Protocol Suite


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IPX/SPX Protocol Suite

HDLC/SDLC


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High Level Data Link Control (HDLC) and Synchronous Data Link Control (SDLC) arebit-oriented synchronous protocols in which data frames are interpreted as series

of bits

Both are useful for half-duplex and full-duplex communication

Windows XP still support DLC

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HDLC/SDLC

Protocols at Different Layers


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Protocols at Different Layers

OSI Layers Protocols

Physical Layer No protocols defined

Data Link Layer HDLC, SDLC

Network Layer NetBEUI, IP, ICMP, IGMP, ARP, RARP, IPX

Transport Layer NetBEUI, TCP, UDP, SPX

Session Layer NetBIOS, SAP, SMTP, FTP, DNS, SNMP,

Presentation Layer NCP, RIP, NLSP, SMTP, FTP, DNS, SNMP, NFS

Application Layer SMTP, DNS, SNMP, NFS, TFTP

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TCP/IP Services and Applications

Simple Mail Transfer Protocol (SMTP)


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Specifies how mail should be delivered from one system to another Standard protocol used for transferring email from one computer to another

Makes connection between senders server and recipient and then transfer

messages

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p ( )

SMTP Work Flow


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A two-way transmission channel established between the sender SMTP and a

receiver SMTP

Commands are generated by sender SMTP and sent to receiver SMTP

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Hypertext Transfer Protocol (HTTP)


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Set of rules used to exchange files on World Wide Web Users can exchange text, graphic images, sound, video and other multimedia files

Defines how messages are formatted and transmitted over the Internet

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yp ( )


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File Transfer Protocol (FTP)


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Used over Internet to exchange files Uses Internet's TCP/IP protocols to enable data transfer

Establishes two way connections between computers

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File Transfer Protocol (FTP)

FTP Communication


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Machine that are involved in an FTP transactionClient (local host) machine and aserver (remote host)

Client machine initiates transfer

Get command used to

copy files from server to

client Put command is used to

copy files from client to server

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Trivial File Transfer Protocol (TFTP) - I


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Used to transfer files to and from a remote computer Used by servers to boot diskless workstations, X-terminals and routers

Start with a small amount of built-in software

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Trivial File Transfer Protocol (TFTP) I


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Simple Network Management


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Framework for managing devices over Internet using TCP/IP protocol suite

Provides set of fundamental operation for monitoring and maintaining devices in the

network

Agent is server process that maintains Management Information Base (MIB)

database for host

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p g

Protocol (SNMP)

Post Office Protocol (POP)


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Used to retrieve email from remote server to local client over TCP/IP connection

E-mail clients using POP3 connect, retrieve all messages or store them on user's PC asnew messages or delete them from server and disconnect

POP3 is a TCP/IP client/server protocol

Session States:

Authorization State

Transaction State

Update State

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Internet Message Access Protocol


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Enables the users to work with the mail on the server Does not download the mails

Used to access e-mails from a local server

Working with mails

Accessing and deleting mails

Attachments

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g

(IMAP)

BOOTP and DHCP - I


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BOOTPFirst automated configuration tool for IP hosts

BootstrappingProvides the host with the capability of getting IP addresseswhile machine boots

Requires two phases:

Client provided with address and other parameters

Client downloads softwares to function on network and perform tasks

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TELNET


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Network protocol used on internet or local area network connections Terminal emulation program for TCP/IP networks

Enables to control server and communicate with other servers on network

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World Wide Web (WWW) - I


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WWW is a network of Internet servers, which support documents that aredeveloped using HTML

Hyper Text Markup Language (HTML) is a language in which these documents are

formatted

Client-side

Computer applicationWeb browser that runs on users local computer and

connects to server

Interpreter that interprets code in an HTML page

Operations carried out on client-side

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Wireless Networking

Wireless Networking Basics


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Wireless networking allowsyou to establish: Communication using standard network

protocols

Communication without the use of

cables

Technologies used for wireless access

based on

Wireless fidelity (Wi-Fi)

Home Radio Frequency

(HomeRF)

Types of Wireless Network I


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Peer-to-Peer(P2P) or Ad-Hoc

Connected wirelessly with the use of wireless Network

Interface Card (NIC)

Computers can access printers and share files

Wired LAN can be accessed using bridging

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Types of Wireless Network II


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Access point orInfrastructure wirelessLAN

Wireless device connectsto the access point to

connect to the network Access point acts as a hub

to connect two wirelessdevices

Wireless bridge used to

connect wireless networkto wired network

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IEEE 802.11


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Security Four methods of wireless network security:

Data encryption - WEP (Wired Equivalent Privacy) and

WPA (Wi-Fi Protected Access)

Port based access control Service Set Identifier (SSID)

Media Access Control (MAC) address filtering

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Medium


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Wireless medium is an unguided form of networking

medium

Wireless transmission involves use of technologies

such as Bluetooth, Infrared, Lasers, Radio signals and

Microwave technologies

Mobile computing allows users to do their work at any

location

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Access Point and Extension Point


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Access Point Device that bridges a wireless connection and a

wired connection

Two types of access points: Hardware access points

and Software access points Extension Point

Used if single access point is not able to cover entire

area

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Hardware Access Points


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Hardware access point is a physical device that is

used to establish a connection between a wirednetwork and a wireless network

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Software Access Points


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Software Access Points are computer whichincludes a wireless network interface card.

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Extension Point


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Extension points are used if a singleaccess point is not able to cover theentire area.

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Antennas and Adapters


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Antennas are used to increase the range ofwireless network

Types of antennas used: Omnidirectional antennas - Used indoors and small in

size Directional antennas - High gain and used for long

range outdoor use

Wireless adapters help to connect computer orPDA to a network

Wireless adapters are available as PC cards, PCI

and mini PCI, USB, and CompactFlash.

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Wireless Station and Server


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Wireless Local Area Network consists of

wireless station and wireless server

Wireless station - Connects wireless network

into a wireless medium

Wireless Stations

Wireless Clients Access Points

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Wireless server The main server which controls

all devices within the wireless network

Software


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Wireless network adapter requires two types ofsoftware so as to function properly:

Driver

Configuration Utility

Windows XP has built-in tools for configuringnetwork adapter settings

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Cisco Router Configuration Basics

Router is a device that acts as interconnect to two networks

WHAT IS A ROUTER


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Tpyesof router

(a) Hardware router

(b) Software router

Hardware routers are small boxes which run special software created by their

vendors to give them the routing capability and the only thing they do is simply

route data from one network to another. Most companies prefer hardware routers

because they are faster and more reliable, even though their cost is considerably

more when compared with a software router

Software router


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Software routers do the same job with the above hardware routers (route data),but they don't come in small flashy boxes. A software router could be an NT server,

NetWare server or Linux server. All network servers have built-in routing

capabilities.

Router Vendors


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Cisco

Juniper

Alcatel

Zdnet etc.

Cisco hierarchical model


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Cisco has three hierarchical model Core layer

Distribution

Acces layer

Difine the layer


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Core layer: This layer is considered the backbone of the network and includes thehigh-end switches and high-speed cables such as fiber cables. This layer of the

network does not route traffic at the LAN. In addition, no packet manipulation is

done by devices in this layer. Rather, this layer is concerned with speed and ensures

reliable delivery of packets


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Distribution layer: This layer includes LAN-based routers and layer 3 switches. This layer

ensures that packets are properly routed between subnets and VLANs in your enterprise.This layer is also called the Workgroup layer

Access layer: This layer includes hubs and switches. This layer is also called the desktop layer

because it focuses on connecting client nodes, such as workstations to the network. This

layer ensures that packets are delivered to end user computers.

cisco hierarchical model Example


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Fixed & Modular Router


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Modular Router- In modular router the interfaces are not fixed so that we will be

able to installed cards later on this router

Fixed RouterIn non modular router the interfaces fixed we can not able to add

ports/interfaces later on

Router Components


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Bootstrapstored in ROM microcode

brings router up during initialisation, boots router andloads the IOS.

POST Power On Self Test - stored in ROM microcode checks for basic functionality of router hardware anddetermines which interfaces are present

ROM Monitor stored in ROM microcodeused formanufacturing, testing and troubleshooting

Mini-IOSa.k.a RXBOOT/boot loader by Cisco small IOS

ROM used to bring up an interface and load a Cisco IOSinto flash memory from a TFTP server; can also perform a

few other maintenance operations


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Introduction of Cisco IOS


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How a Cisco device locates and loads IOS The default source for Cisco IOS software depends on the hardware platform, but

most commonly the router looks to the boot system commands saved in NVRAM

Cisco IOS software allows several alternatives to be used. Other sources can be

specified for the software, or the router can use its own fallback sequence to load

the software

MANAGING CISCO IOS


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The value in the configuration registertells the router where to get the IOS

This can be confirmed by using the

show version command and looking atthe last line for the configuration

register

MANAGING CISCO IOS


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MANAGING CISCO IOS


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Managing configuration files using TFTP Enter the command copy running-config tftp.

At the prompt, enter the IP address of the TFTP server to store the configuration

file.

Enter the name to assign to the configuration file or accept the default name.

Confirm the choices by typing yeseach time.

MANAGING CISCO IOS


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MANAGING CISCO IOS


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Enter the command copy tftp running-config.

At the prompt, select a host or network configuration file.

At the system prompt, enter the IP address of the TFTP server where theconfiguration file is located.

At the system prompt, enter the name of the configuration file or accept thedefault name.

Confirm the configuration filename and the server address that the systemsupplies.

Router Basics Commands


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You can tell in which area of the routers configuration you are by looking at the router

prompts:

Router>USER prompt mode

Router#PRIVILEGED EXEC prompt mode

Router(config)terminal configuration prompt

Router(config-if)interface configuration prompt

Router(config-subif)sub-interface configuration prompt*

Router Basics Commands


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Router(config)# hostname hpes

Router(config-if) no shut

Router(config-if) shut

Set Banner to Router

Router(config) banner login (telnet) . welcome tp hpes .

Router(config) banner motd. (message of the day Banner

Set Router Passwords


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Router(config) line console 0

Router(config-line) password hpes Router(config-line) login

Set administrative mode Password

Router(config) enable password hpes

Router(config) enable secret hpes

Set Telnet Mode Passwords

Router(config) line vty 0 4

Router(config-line) password hpes

Router(config-line) login

Break Password on Router


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Power-cycle the router when Router is boot press+Ctrl+Break

Rouer will come Rommon mode

Rommon >Confreg 0X2142

Rommon>reset

Continue with configuration dialog pesss No

Router will come user mode

Router>enable

Router# copy Startup-config Running-config

Router(config)# enable password hpes1

Router(config)# config-register 0x2102

Router# copy running-config startup-config Router# reload

Routing


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What is Routing> Routing is the process of sending a packet of information from one

network to another networks,routes based on the destination network

The Administrative Distance of Common Routing Protocol

OConnected

1Static

20BGP

Internal EIGRP90

IGRP100

OSPF110

RIP - 120

Routing Type


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There are two basic methods of building a routing table: Statically and Dynamically

Static

1. Static routing table is created, mainted and updated by a network Administrator,

manually

2. Static routes have an administrative Distance is 1

3. Static will not share Static routes with each other

4. When there is low bandwidth Connectivity

5. When an administrator wants total control over the route

6. When hardware router is not able to handle routing updates

Dynamic Routing


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A dynamic routing table is created, maintained , and updated by a routing protocol

running on the router Example-(RIP,EIGRP,OSPF,IGRP)

Dynamic Routing Categories


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There are two type of dynamic Routing Protocol

1. Distance-vector routing Protocol

2. Link-state routing Protocol

Example of distance vector routing protocol (RIP,IGRP)

Example of link state Routing Protocol (OSPF,IS-IS)

EIGRP both distance-vector and link state routing Protocol

Distance Vector


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1. distance Vector is classfull Routing protocol

2. periodic updates of the full routing table are sent to routing neighbors.

3. Distance vector routing protocol is used Bellman-Ford algorithm. Distance vector routing protocol begins by advertising directly connected networks to its

neighbors. (RIPevery 30 seconds; IGRPevery 90 seconds)

Distancevector protocols utilize some form of distance to calculate a rotesmetric.

Link State Routing Protocol


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Classless routing protocol

Support for VLSM

Connection Oriented protocol

Trigger update support

Link state routing protocol is used Dijkstra algorithm

Link state routing protocol maintain 3 seprate tables.

A. Neighbor Table

B. Topology Table

C. Routing Table

RIP is a standardized Distance Vector protocol, designed for use on smaller networks.

RIP v1 (Routing Information Protocol)


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RIP sends out periodic routing updates (30 sec)

RIP sends out the full routing table every periodic update.

RIP uses a form of distance as its metric hopcount 15 (max.)

RIP uses the Bellmanford Distance Vector algorithm to determine the best path to particular

destination


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RIP support only Classfull IP routing protocol

RIP send updates as broadcasts to address 255.255.255.255 RIP v1 not support VLSM

RIP support IP and IPX routing

RIP routes have an administrative distance of 120

Hop countno of routers in between the route

RIP Timers


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Update Timer (Default 30 seconds)- indicates how often the router will send out a routing

table update.

Invalid Timer (Default 180 seconds)- If no new updates are heard about this route. The invalid

timer will be reset if an update is received for that particular route beforethe timer expires.

Hold-down Timer(Default 180 sec)rip will not accept any new updates for routes in hold-down

state, until the hold-timer expires

Flush Timer (Default 240 Seconds)- indicates how long a route can remain in a routing table

before being flushed, if no new updates are heard about this route.

RIP v1 Basic Configuration


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Router A

Router(config)# router rip

Router(config-router)# Network 172.16.0.0


Router B




Router A Router B

172.16.1.2/16 172.17.1.1/16

172.17.1.2/16

172.18.1.1/16

RIP v2 (Routing Information Protocol)


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RIP is a standardized Distance Vector protocol, designed for use on smaller networks.

RIP sends out periodic routing updates (30 sec)

RIP sends out the full routing table every periodic update.

RIP uses a form of distance as its metric hopcount 15 (max.)

RIP uses the Bellmanford Distance Vector algorithm to determine the best path to particular

destination


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RIP support only Classless IP routing protocol

RIP send updates as multicasts address 224.0.0.9 RIP v2 support VLSM

RIP support IP and IPX routing

RIP routes have an administrative distance of 120

RIP v2 Basic Configuration

Router B172 16 1 2/16172.17.1.1/16 172.18.1.1/16


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Router A


Router(config)# version 2



Router B


Router(config)# version 2



Router A Router B172.16.1.2/16 /

172.17.1.2/16

EIGRP (Enhanced Interior Gateway Routing

Protocol)


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EIGRP is a Cisco-proprietary Hybrid routing protocol, incorporating features of both

Distance-Vector and Link- State routing protocols.

EIGRP uses Diffusing update algorithm to determine the best path among all

feasiblepaths.

EIGRP will form neighbor relationship with adjacent routers in the same

Autonomous System (AS)

EIGRP uses multicasts on address 224.0.0.10.

EIGRP routers do not send periodic, full-table routing updates.


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EIGRP routers do not send periodic, full table routing updates.

EIGRP is a classless protocol and thus supports VLSMs.

EIGRP supports IP, IPX, and Appletalk routing. EIGRP Administrative Distance is 90.

EIGRP uses Bandwidth and Delay of the Line by default, to calculate its distance

metric Reliability, Load and MTU.

EIGRP has a maximum hop-count of 224,


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EIGRP Neighbors


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EIGRP forms neighbor relationships in the same AS by exchanging Hello packets.

Hello packets are sent multicast address 224.0.0.10

EIGRP hellos packet are sent every 5 seconds. (high speed wan),slower links are

send every 60 seconds

Hold timer is three times of Hello timer High speed 15 second, slow link 180

seconds.

Configuring EIGRP


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Router A

RouterA(config)# router eigrp 10

RouterA(config-router)# network 20.0.0.0


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RouterA(config-router)# network 10.0.0.0

Router B

RouterB(config)# router eigrp 10

RouterB(config-router)# network 20.0.0.0

RouterB(config-router)# network 172.31.0.0

Router C

RouterC(config)# router eigrp 10RouterC(config-router)# network 172.31.0.0

RouterC(config-router)# network 192.168.10.0

OSPF (Open Shortest Path First)


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OSPF is a standardized Link-State routing protocol, designed to scale efficiently to

support larger networks.

OSPF allows for a hierarchical network design through the us of Areas

OSPF uses the Dijkstra shortest path first algorithm.

OSPF is a classless protocol, and thus supports VLSMs.

OSPF Traffic is multicast 224.0.0.5 (all OSPF routers) or 224.0.0.6 ( all

Designated Routers)


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Router ID Selection


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Router ID can be manually specified

The highest ip address configured on any Loopback interface on the router

will become the Router id

If no loopback interface exits the highest ip address configured on any

physical interface will become the Router ID

OSPF Hello packets are sent out on interface every 10 seconds for broadcast

and point-to-point interface and 30 seconds for non broadcast point to

multipoint interface

OSPF also has a Dead Interval , which indicates how long a router will wait without

hearing any hellos before announcing a neighbor as down Default for Dead Interval


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hearing any hellos before announcing a neighbor as down . Default for Dead Interval

is 40 Seconds for broadcast and point-to-point interfaces, and 120 seconds for non-

broadcast and point-to-multipoint interfaces

Down indicates that no Hellos have been heard from the neighboring router.

Init indicates a Hello packet has been heard from the neighbor.

e g or a es


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2-Way indicates that bidirectional communication has been established.

ExStart indicates that the routers are preparing to share link state information.Exchange indicates that the routers are exchanging Database Descriptors.

Loading routers are sharing their topology tables with each other.

Full indicates that the routers are fully synchronized.

Configuring OSPF


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Router A(config)# router ospf 1

Router A(config-router)# network 10.0.0.0 0.255.255.255 area 0

Router A(config-router)# network 20 0 0 0 0 255 255 255 area 0


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Router A(config router)# network 20.0.0.0 0.255.255.255 area 0

Router B(config)# router ospf 1

Router B(config-router)# network 20.0.0.0 0.255.255.255 area 0Router B(config-router)# network 30.0.0.0 0.255.255.255 area 1

Router C(config)# router ospf 1

Router C(config-router)# network 10.0.0.0 0.255.255.255 area 0

Router C(config-router)# network 40.0.0.0 0.255.255.255 area 2

Router D(config)# router ospf 1

Router D(config-router)# network 30.0.0.0 0.255.255.255 area 1

Router E(config)# router ospf 1

Router E(config-router)# network 40.0.0.0 0.255.255.255 area 2

VLANs is used to control broadcast domain.

Advantages of VLANs

r ua


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Advantages of VLANs

Broadcast Control Broadcasts are received by every host on the switched network. In

contrast, each VLAN belongs to its own broadcast domain (or IP subnet); thusbroadcast traffic from one VLAN will never reach another VLAN.

Security VLANs allow administrators to logicallyseparate users and departments.

Flexibility and Scalability VLANs remove the physical boundaries of a network. Users

and devices can be added or moved anywhere on the physical network, and yet

remain assigned to the same VLAN.

VLAN Membership


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VLAN membership can be configured one of two ways:

Statically Individual switch-ports must be manually assigned to a VLAN.Dynamically Devices are automatically assigned into a VLAN based on its MAC

address. Cisco developed a dynamic VLAN product called the VLAN Membership

policy Server (VMPS).

Cisco switches support two frame-tagging protocols, Inter-Switch Link (ISL) and IEEE802.1Q

Inter-Switch Link ISL is cisco sproprietary frame-tagging protocol ISL encapsulates a

frame with an additional Header(26 bytes) and 4 bytes Trailer, increasing the size of an

ethernet frame up to 30 bytes. The header contains the 10 bytes VLAN ID, non-ISL

devices (non-Cisco devices) will actually drop ISL-tagged frames.


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IEEE 802.1Q IEEE802.1Q, otherwise known as DOT1Q, is the standardized

frame tagging protocol supported most switch manufacturers By default configure VLAN 1 and VLAN 1002-1005

Configure VLAN


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Switch(config)#vlan 2

Switch(config-vlan)#name sales

Switch(config-vlan)#exit


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Switch(config-vlan)#exit

Switch(config)#vlan 3

Switch(config-vlan)#name it

Switch(config)# vlan 4

Switch(config-vlan)# name HR

Switch# show vlan

Add pc to Vlan

Switch(config)# int fa0/1

Switch(config-if)# switchport access vlan 2

Add other PC to Vlan

VTP (VLAN Trunking Protocol)


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In large switching environments, it can become difficult to maintain a consistent

VLAN database across all switches on the network. VTP allows the VLANdatabase to be easily managed throughout the network.

By default, VTP updates are sent out every 300 seconds.

Server Only VTP servers can create modify or delete entries in the VLAN database

VTP Modes


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Server Only VTP servers can create, modify or delete entries in the VLAN database.

Servers advertise their VLAN database to all other switches on the network. Server

can only advertise VLANs 1-1005

Client VTP clients cannot make modifications to the VLAN database, A client will also

forward an update from a server to other clients.

Transparent VTP transparent switches will not advertise or accept any VLAN database

information from other switches (even a server).

Access Control Lists


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ACLs can be used for two purposes on Cisco devices to filter traffic, and to

identify traffic.

ACL can be configure inbound and outbound.

Two types of configure Access lists

Named and Numbered

IP standard access list 1-99

IP extended access list 100-199

Standard ACLs


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Standard access list based on layer 3 information, it is based on Source

address, it is created on destination Router destination port as outbound

Extended access list based on layer3 and layer 4 information it is based

Source address as Source port as inbound


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advance concepts of networking

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