IP Configuration

Network – When systems connected to each other to share resources and data in a network is known as networking.

Point to Point Configuration

It is dedicated link exits between two devices.

Multipoint

When two or more device shares a link.

Topology

It is the physical structure (design) in which they are connected to each other.

Types of topologies

1. Physical topology - It refers to arrangement of devices in a network they are BUS, Star, Tree, mesh.

2. Logical topology - It represents the way in which data is transferred from one device to next device irrespective of physical connection.

Bus topology

In this device share a common backbone cable to send and receive data.

Ring topology

In this each device is connected to adjacent devices forming a circle data flows in one direction only clockwise.

Star topology

In this topology multiple devices are connected to central connection point as hub or switch.

Mesh topology

In this device is connected to each other two mesh topology.

Full mesh topology

Each mode is connected to each other.

Partial mesh topology

It does not connect to each other it is very expensive.

Tree topology

It combines linear bus and star topology.

A backbone is used to connect multiple star networks.

Types of network

Lan – local area network

It is a small area network to share data and resources.

Types of lan

1. Ethernet – used IEEE 802.3 standard and csma and cd technology 2. Token ring – passes s token over the network in ring format 3. Token bus – uses token mechanism the system are physically connected in bus format 4. FDDI – it uses token passing technique like token ring network. It uses primary and secondary

rings.CAN – Campus Area network

It is area network which is limited to a campus.

MAN – Metropolitan Area network

It is an interconnection of networks in a city.

WAN – Wide Area network

Wide network consists of geographical area which includes multiple computers or LANs.

Modes of Transmission

1. Simplex – It is unidirectional one devices transmit and other device data. 2. Half Duplex – Uses only one wire to connected network and transmits data. It uses CSMA /CD to

avoid collision only one device communicates eg. Walkie-talkie 3. Full-Duplex – It uses two wires for communication one for sending and one for receiving there is

no threat of data collision both devices communicate at a time. Ethernet

1. It is a standard communication protocol embedded in software and hardware devices for LAN.2. It uses bus or star topology. 3. Ethernet is frame based it uses baseband signalling and implies CSMA/CD. 4. Types of Ethernet are 10base2, 10baseT, 10base5 and 100baseT.5. [Baseband – it sends a single signal at a given instant]6. Works on IEEE 802.3 standard. 7. Developed by DEC, Intel, Xerox corporation

Devices

HUB – It is a device which contains a series ports to which computer can connect joins multiple network segments together to form a single segment

Feature

One broadcast, shares the bandwidth, one collision domain.

Working

When any transmission received on one port it will be sent at all ports in a hub and collision is checked out through CSMA/CD

Switch – It is also a device which connects multiple LAN segments at data link layer.

Working

It examines data packets for sources and destination MAC address to sent it on respective port in case if destination is unknown than it acts like hub and floods the frame to every port

Types of switch

1. Managed switch – this type of switch uses SNMP which sets the communication parameter as per requirement of network it shows number of bytes and frames transmitted or received and number of error on each port.

2. Unmanaged switch - If Ethernet devices start to communication on connection One broadcast domain, multiple collision domain, switch has its own VLAN.

Types of switching

1. Cut through switching – These types of switches forward data packets as soon as they receive it. They validate data by comparing checksum value.

2. Store and forward switching - It performs a checksum on each data packets before forwarding it. This switch is slower than previous switch. These switch minimize the errors due to improper packet forwarding.

3. Fragment free switch – It checks first 64 bytes of data. It provides a balance cut through switch and store and forward.

Bridge – All features are same of hub but it has MAC table.

Router – It is a device that provides the best possible route to data packets to reach destination they use routing table to decide route of data. Join multiple network using different protocols. Operate at network layer.

Function of router

1. Provide traffic management 2. Do not pass broadcast traffic 3. Connect different network segment.

Repeater – It is a device that increases the strength of data signals sent across the network it amplifies and passes it on next segment.

Bridges – Devices that divide network into different segments. It decides network segment where the data has to travel in order to reach its own destination.

OSI Model

Open System Interconnection

1. This model was developed by ISO - international standard organisation 2. It is a set of guidelines that application developers can use to create and implements application

that run in network.3. It provides a framework for creating and implementing networking standard, devices and

internetworking schemes.Note- devices that operates on all seven layers are as follows

1. Network management stations 2. Web and application services 3. Gateways and network host

It has seven layers divided into two groups.

1. Top three layers define how application within the end stations will communicate with each other and with users.

2. Bottom four layers define how data is transmitted end to end.Layers

1. Application – files, print, message, database, application2. Presentation – data encryption, compression and translation.3. Session – dialog control 4. Transport – end to end connection 5. Network – routing 6. Data link – framing 7. Physical – physical topology

Application layer – It defines the manner in which application interact with network like database e-mail. It provides user interface protocol that work on this layer FTP,TFTP,SMTP, DNS, SNMP, NFS, NNTP

Presentation layer – It defines the way in which data is formatted, presented, converted and encoded. Presents data and handles processing such as encryption.

Session layer – Co-ordinates communication and maintains session for as long as it is required performing security logging and administrative functions. Keeps different applications data separate.

Transport layer – It defines protocols for structuring messages and supervises the validity of transmission by performing error checking. Provides reliable or unreliable delivery. Performs error correction before retransmit.Protocols that works are TCP, UDP, SCTP.

Network Layer – It defines data-routing protocols to increase the likelihood that information arrives at correct destination node. Devices that work on this layer is routers and firewalls. Provides logical addressing which routers use for path determination.Protocols that work are ICMP, IGMP, IP,ARP, RARP.

Data link layer – Validates the integrity of flow of data from one node to another by synchronizing blocks of data and controlling the flow. Combines packets into bytes and bytes into frames. Provides access to media using MAC address. Performs error detection not correction.Protocols that works are HDLC, SDLC.

Physical layer – It defines mechanism for communicating with tansmission medium and interface hardware. Moves bits between devices. Specifies voltage wire speed and pin out of cables.

Protocols – These are sets of rules to determine how data is transmitted over the network it works on several levels. Hardware level software level program level.

Protocols are predefined set of rules which govern the transfer of data and communication between computers connected in a network.

Functions of protocols

Regulate type of networks access method Compression techiques Topologies Cabling methods Speed of data transfer.

Ethernet – It is a standard communication protocols embedded in software and hardware devices for lan.

1. Uses bus or star topologies 2. It is based on frames 3. It uses baseband signalling and implies CSMA / CD4. Types of Ethernet are 10base2, 10baseT, 10base5, 100baseT.5. Works on IEEE 802.3 standard.

6. Developed by DEC, INTEL, XEROX corporation.Note – It is the only technology to support two different topologies.

Ethernet frames

It is used to encapsultes packets handed down from network layers. It perform a data security check and ensures that data is not corrupted.

It is made up of two sub layers.

1. MAC – Media access control 2. LLC – Logical link control.

Frame

Destination address – 6 bytes / 48 bits

Source address – 6 bytes / 48 bits

Length – 64 bytes / 1024 bits

Frame check sequence total 1632 bits

IEEE standards 802.3 – Institute of electricals and electronics engineers.

MAC 802.3 – It defines how packets on media are placed. MAC address is of 48 bit (12 digit hexadecimal number) divided into two parts. MM:MM:MM:SS:SS:SS

On first part it represents manufacturers identifier provided by IEEE. Second part represents a serial number provided by manufacturers.

LLC – Logical link control 802.2

It is responsible for identifying network layer protocols and then encapsulating them. It also provides flow control and sequencing of control bits.

DTE – Data Terminal Equipment

Devices which communicates on Ethernet network such as computer and printer.

DCE – Data Communication Equipment

Devices which provide communication on Ethernet eg. Switch and router.

IEEE 802 networking standard

1. 802.1 – LAN /MAN management (internetork ) 2. 802.2 – Logical link control 3. 802.3 – CSMA /CD 4. 802.4 – Token Bus 5. 802.5 – Token Ring 6. 802.6 – MAN – Distributed Queue Dual Bus 7. 802.7 – Broadband 8. 802.8 – Fibre Optic LAN and MAN 9. 802.9 – ISDN Isochronous LAN 10. 802.10 – Network Security 11. 802.11 – Wireless (a to n)12. 802.12 – Demand Priority Access Method 13. 802.15 – Wireless Personal Area Network 14. 802.16 – Wireless MAN 15. 802.17- Resilent Packet Ring 16. 802.18 – LAN/MAN Standard Commitee

Cable Standard for UTP

1. Cat 1 – telephone (carries only voice) 2. Cat2 – 4Mbps 4 pairs of wires 3. Cat3 – 10 Mbps RJ45 16 Mhz 4. Cat4 – 16 Mbps 20 Mhz 5. Cat 5 – 10 Mbps 100 Mhz6. Cat6 – 1000 Mbps 250 Mhz 7. Cat7 – 600 Mhz

Data link layer for Ethernet

It works on physical address known as MAC address i.e. of 48 bit (6 bytes) denoted by haxa-decimal digit. Responsible for converting packets into frames and transmitting to network layer. It encapsulates data and media access control which check error in data during and after reception. It’s sub layer LLC provides error detection and flow control.

SNAP- Sub Network Access Protocol

IEEE defines two frames SAP and SNAP in LLC that handle the data link layer.

SAP – Service Access Point

This frame is of one byte in length and uses only first 6 bits to identify network layer protocols.

i.e. 2^6 =64 protocols only

SNAP – This frame is of 2 byte so it can identify upto 65536 protocols.

TCP/IP Model

Allows data transfer between network device

TCP – It is transport layer of the protocol and serves to ensure a reliable verifiable data exchange between hosts on a network breaks data packets into segments number them and send in random order.

IP – It is responsible for network addressing routing connectionless and reliable

DOD Model (Department of Defence) TCP/IP Model

Four layers of DOD Model

1. Application Layer 2. Host to host layer 3. Internet layer 4. Network access layer

Application layer – Defines application such ad FTP Telnet interact through this layer.

Protocols that function on this layer

SNMP FTP TFTP SFTP

SMTP POP3 IMAP HTTP

NNTP IGMP NTP NFS

LDAP

Host to host layer

Adds transport control information to user data. Responsible for source to destination delivery of entire message.

Internet layer

It allows routing of data over the network. Adds IP information to form a packet ARP and RARP works on this layer.

Network interface layer

In this layer protocols that are used to transmit data to other device in network transmit data frames in network over the physical connection exchange data between devices.

Application layer protocols

Telnet – It allows a user on a remote client machine to access the resources of another system.

FTP – File Transfer Protocols (port 20,21)

Used over internet to exchange files it can download a file from a server or upload a file to server. It is limited to listing and manipulating directories typing fules contents and copying files between hosts. Authentication required.

TFTP – Trivial File Transfer Protocol.

It is used to transfer files to and from a remote computer such a diskless workstations. These workstations do not have their own storage disk and boots from a network host or a server.

It has no directory browsing abilities it can do nothing but send and receive files uses UDP. No authentication required.

NFS – Network File System

It allows two different types of file system to interoperate. Developed by SUN microsystem so that UNIX server can communicate with TCP.

SMTP – Simple Mail Transfer Protocol

It is used for transferring mail from client to server and server to server.Specifies how mail system work together and the format control message they use to exchange and transfer mail.

LDP – Line printer daemon

It is designed for printer sharing. It allows print jobs to be spooled and sent to networks printers using TCP/IP.

SNMP – Simple Network Management Protocol

It allows network administrator to collect information and remotely monitor other devices on network. It gives smart devices such as routers, switches, hubs, bridges, PC’s to report their status and allows administrator to make changes.

It uses two protocols.

1. SMI2. MIB

SMI – Structure of management Information

It defines the rules and does not define how many objects are managed in an entity SMI sets the rule for naming objects types and shows how to encase objects and values.

MIB – Management Information Base

It creates a set of objects foe each entity that is similar to normal database. It defines the number of objects name the objects with respect to rules defined by SMI.

X-Window – It defines a protocol for writing client/server application based on graphical user interface.

NNTP – Network News Transfer Protocol

It is standard protocol used to transfer UseNet news from one machine to other UseNet news is a large collection of discussion group covering a wide range of topics. Provide connection – oriented service. Gives failure – delivery message (error generation)

SFTP – Secure File Transfer Protocol

It is used to transfer files over an encrypted. it uses an SSH session which encrypts the connection.

POP - Post Office Protocol.

It provides a storage mechanism for incoming mail. All messages are download to client for POP3 server.

IMAP – Internet Message Access Protocol

It allows user to download mail selectively current version is IMAP4.

SSH – Secure Shell

It is used to establish secure telnet session used to run programs on remote system. Log into other system and move files maintaining strong encrypt connection.

HTTPS – Hyper text transfer protocol secure

Allows browser and servers to sign authenticate and encrypt an HTTP message.

NTP – Network Time Protocol.

It is used to synchronize computer clock to some standard time source which is usually a nuclear clock.

SCP – Secure Copy Protocol

It used SSH to establish and maintain an encrypted connection between host. The file transfer can then take place without fear of password or data interception.

LDAP – lightweight directory access protocol

It keeps track of user and resources. It allows clients to perform objects lookups with a directory using standard method.

IGMP – Internet Group Management Protocol.

It is used to manage IP multicast sessions. It keeps a track of group membership and active multicast streams.

Transport Layer Protocols

TCP – Transmission Control Protocol

It serves to ensures a reliable verifiable data exchange between a host on a network. It breaks Data into pieces, wraps the needed information; it numbers and sequences each segment so that destinations TCP can put the segment back in order. It is a full duplex connection oriented reliable and accurate protocol. Check the flow control. Error detection.

UDP – User Datagram Protocol

It is connectionless, unreliable protocol. It adds port addresses and error control information to data and deliver the data. It is faster than TCP.

Network Layer Protocol

IP – Internet Protocol

It is connectionless protocol. It does not establish end to end connection before transmission. It’s only job is to route the data to destination.

ARP – Address Resolution Protocol

It finds the hardware (MAC) of a host from a known IP address.

RARP – Reverse Address Resolution Protocol

It is a protocol which finds IP address from its MAC address. It is used by a diskless machine to request for IP address by DHCP server from its address.

Proxy ARP – It is used to allow redundancy in case of a failure with the configured default gateway on a host. Proxy ARP is a variation of a ARP protocol in which an intermediate device such as a router sends a ARP response on behalf of an end node to requesting host.

ICMP – Internet Control Message Protocol

It provides a method for communicating error message and other transmission information. They are (ICMP packets) encapsulated within IP datagram.

Generates four messages

1. Destination Host unreachable – If router or device is unable to deliver IP packets to destination in this case it discards the original packets

2. Network unreachable – When packet fails to reach destination.3. Host unreachable – When packet fails if subnet is wrong.4. Protocol unreachable – When destination does not support upper layer protocol.5. Port unreachable – When TCP socket is not available.

Echo Request Message – It checks whether another device is reachable or not.Request Message – ICMP redirect requires address of only one router to forward packet for efficient routing.

Time exceeded Message – Router sent IP packet when time reaches zero it discard original packet after time out.

Cisco Model

This model consists of 3 functional layer

1. Core layer2. Distribution layer3. Access layer

Core layer – This main layer is responsible for fast, reliable communicating of data across network. It reduces latency time in delivery of packets.

Factors

1. High data transfer rate 2. Low latency period 3. High reliability

Distribution layer – This layer is used for routing and managing network traffic, manipulates packets by queuing.

Factors

1. Packets filtering – regulates packet by source and destination address.2. Access layer aggregation point – serves as aggregation point.3. Control Broadcast and multicast – serves as boundary and multicast domains.4. Application gateways – create protocol gateways to from network architecture.5. Implementing Security and network policies.

Access layer – Ensures that packets are delivered to destination, allows workgroup and user to utilize services provided by distribution layer and core layer.

Functions

1. Address filtering – allows selected system to access LAN. 2. Separate collision domains – creates collision domain for each node.3. Share bandwidth – enable network to handle all data.4. Handle switch bandwidth – perform load balancing.

IP Addressing

It is a numeric identifier assigned to a machine over the network.

IP terminology

1. Bit – Digit either 0 or 1 2. Byte – It is a pair of 8 bits.3. Octet – an octet is made up of 8 bits 4. Network address – It is used in routing to send packet to a remote network.5. Broadcast Address – It is used by application and host to send information to all nodes on a

network.

IP has two version (Ranging from 0 to 15)1. IP version 4 binary

2. IP version 6 hexadecimal

IP version 4 – It is of 32 bits divided into four sections through dot.

Classification of IP address

00000000.00000000.00000000.00000000 = 32 bits

Class A 1 to 126 8 bit network bits 24 bits host bits

10.0.0.0 to 10.255.255.255 private address

127.0.0.0 – 127.255.255.255 loopback address used for testing

0 and 1 bit is reserved 2 ^7 = 128 – 2 = 126 network

Class B 128 – 191 16 bit network 16 bit host bits

172.16.0.0 – 172.31.255.255 private address

1,0 two bits are reserved 2 ^ 6= 64 networks

Class C 192 -223 24 bit for network 8 bit host bits

192.168.0.0 – 192.168.255.255 private

1,1,0 three bits are reserved 2^5 = 32 network

Class D 224 – 239 used for multicast

1,1,1,0 four bits reserved 2^4 =16network

Class E 240 – 255 used for experiment

1,1,1,1,0 – 5 bit reserved 2 ^3 =8 network

Subnetting – Used in IP networks to break up larger network into smaller subnet.

Supernetting – When we increase number of host bits

APIPA – 169.254.0.0

Public address – routable IP address are known as public address

Private address – non routable IP addresses are known as private address.

Subnet mask – It defines the network portion of the octet and which belongs to host.

Loads of reasons in favour of subnetting

1. Reduced network traffic

2. Optimized network performance 3. Simplified management 4. Facilitated spanning of large geographical distance.

Subnet Mask

Class A 255.0.0.0

Class B 255.255.0.0

Class C 255.255.255.0

CIDR – Classless Inter Domain Routing

It allows a group of IP network to appear to other network as a unified larger entity.

CIDR values

255.0.0.0 /8 255.128.0.0/9

255.192.0.0/10 255.224.0.0/11

255.240.0.0/12 255.248.0.0/13

255.252.0.0/14 255.254.0.0/15

Router – It is network devices that allow directing data traffic to an appropriate destination. They use routing table to decide route of data. Join multiple network using different protocols. Operate at network layer.

Functions of router

1. Provide traffic management 2. Don’t pass broadcast traffic 3. Connect different network segment

Types of router memory

DRAM – Dynamic RAM

Main storage memory for router. It contains dynamic configuration information. It stores a copy CISCO IOS

Non – volatile RAM

It contains a backup copy of configuration for restoration

Flash Memory

It contains copy of CISCO IOS. It is erasable and programmable.

Router components

1. Processor – It executes IOS commands it uses two types of processors like Motorola 68030, Orion. It makes routing decision and maintains routing tables. It requires access to memory to get data for making routing decisions ( to get instruction for execution)

2. ROM - non volatile storage device which decides boot process of router. 3. Post – power on self test

It provides a series of diagnostic test for router in reverse numerical order.4. Bootstrap program – It is rom monitor component that allows you to initialize the processor

hardware when router boots. It loads IOS image for router with the help of configuration register.

5. Configuration register – It is a file that decides the boot mode for ios image.

Function of Bootstrap

Verifies configuration (file) register value

Check NVRAM for boot system commands in startup configuration file.

Mini IOS – it provides an alternate file for router boot up if IOS unavailable.

ROM monitor

It is a program stored in ROM which is used to debug user program.

RAM – It consists of active IOS image that is loaded when the router boots. It stores active configuration files, routing tables and information in input and output buffers of router interface.

Flash - A non-volatile storage medium which contains IOS image through which router boots.

NVRAM – It stores configuration files for router and startup files.

Router boot sequence ********

1. It performs POST to test hardware and memory 2. Bootstrap program is loaded from ROM and execute.3. Load IOS image from specified location (flash/RAM/TFTP server) 4. Locates hardware and software components of router and display list of component on console.5. Executes configuration commands which begins routing processes on router and provide IP

address to router interfaces.

IOS – internetwork operating system

It provides an interface between user and hardware i.e. network devices and user. It is an assembly of commands and functions that allows you to run network device. It allows us to work and configure those commands.

Features of IOS

1. Support different technologies – supports data link layer technologies such as LAN and WAN copper and fibre wiring.

2. Scalability – support different platform so that hardware could be changed without affecting the performance.

3. Security – it enables to control access to network using different security policies.

Ports Console port – used to configure router locally it has 8 pin RJ45 connector connected with

system through rollover cable. Auxiliary port – connects modem to router through straight cable.

Command line interface

Allows manual configuration of router through text based interface. It can be directly accessed through console port.

Router has three modes.

1. User Exec mode 2. Privileged Exec mode3. Configuration mode

User Exec mode – used to check the router status and switch to different modes.

To enter in privileged mode

Router > prompt appears

Router > en

And privileged mode appears as

Router #

Privileged mode – to Executes higher level commands such as security and configuration setting.

To switch to user mode

Router # disable

Configuration mode – it allows you to executes configuration commands for router.

Router # config terminal

Router (config)

To exit from configuration mode ctrl + z

Return to user mode directly exit

Router configuration – It can be done in 3 ways

1. Using security device manager – starts automatically2. Using command line – manual configuration 3. Using setup mode – enables to configure host name, password etc.

Name ways to access prompt

User exec mode access through cable or auxiliary port >

Privilege mode type enable on user mode to check all the configuration #

Mode on router

Global configuration type config-t on privilege exec mode to make changes on (config)#

mode Router configuration.

Interface configuration it is used to make changes on whatever part either it is serial (config-if)#

Mode or fast ethernet to give shutdown or No shutdown the interface

Line configuration if you want to apply password security on different lines. This (config-line)#

Mode configuration mode.(line vty-virtual terminal, AUX, console)

Router configuration if we are going to configure dynamic routing protocols then (config-router)#

Mode this mode comes in existence.

CLI prompt

Interface – to make changes to an interface you use interface command from global configuration mode

Router(config) interface ?

Fast ethernet – fa

Serial – s

Loopback – loopback interface

Router (config)# interface fast ethernet 0/0

Router (config-if)#

Sub-interface – it allows you to create a logical interface within the router

Router (config-if) # interface f0/0.1

Router (config-subif)#

Line commands – to configure user mode password use the line command.

Router (config-line)# any command entered from here is called sub-command

Routing protocol configurations

To configure running protocol such as rip and eigrp

Router (config-router)#

Router# config t

Router (config) #router rip

Router (config-router) # version 2

Router (config-router) #

Banners – it manages displayed to all user when they access the router through telnet console and auxiliary port.

Note – # is used at end at end of banner to indicate it is required it is finished

It is of 4 types

Message of day banner – displayed to all user accessing it through console, telnet or auxiliary port.

Syntax : banner motd [delimiter]

Delimiter character such as comma, fullstop, character or numeric values.

Exec process creation banner – displayed when you create an EXEC process. It can be a line activation or incoming connection to vty (virtual terminal) line.

Incoming terminal line banner – displayed on terminal that use reverse telnet [in this session is initiated by host computer for its user]

Log in banner – it is configured to displayed on all terminals connected to router it can be viewed after MOTD banner and before the log in prompt.

To disable it – no banner login is used

Routing – it is the process of transferring data from the source to destination. It determines the best path for packets from one device and sends it through the network to other device.

Minimum requirement for routing

1. Destination address 2. Neighbour routers from which it can learn about remote networks3. Possible routers to all remote network4. The best route to each remote network 5. How to maintain and verify routing information

Goals of routing

Stability- Information or packets are routed by using optimal path. Provides with a robust network – while routing protocols take care of hardware failures, high

load conditions. Dynamic update of network paths – protocols are capable of updating the routing paths. Information is safe while transmitting by internetwork router.

There are 3 types of routing

1. Static routing 2. Dynamic routing 3. Default routing

Static routing – when we manual adds router in each router’s routing table is known as static routing. Its administrative distance is 1. It’s totally based on admin intervention.

In static routing we have to give the hop information of next hop.

Benefits of static routing

There is no overhead on router CPU which means you could buy a cheaper router.

There is no bandwidth usage between routers

It adds security because administrator can choose to allow routing access to certain network only.

Disadvantages

The administrator must really understand the internetwork and how each router is connected

Not feasible for large network

If network is added to a internetwork, the administrator has to add the route manually

Syntax

Ip route [destination –network][mask][next-hop-address or exit interface][AD] [permanent]

Ip route – command used to create the static route

Destination-network – network you are placing in routing table

Mask – subnet mask being used on network

Next hop address – the address of next hop router that will recieve the packets and forward it to remote network.

Exit interface – used in place of next hop address if you want and show up as a directly connected route.

AD- administrative Distance

By default static route have an administrative distance of 1

Permanent – if the interface is shut-down or the router cannot communicate to next hop router.

Configure IP address on interface E0 on router A

Router >en

Router #config t

Router (config) # hostname R1

R1(config)# int e0/0

R1 (config-if)# ip add 172.16.10.1 255.255.255.0

R1 (config-if)# no shut

R1 (config-if)# ip add 172.16.20.1 255.255.255.0


Router B

Router >

Router # config t

Router (config)# hostname r2

R2 (config)# int e0/1

R2 (config-if)# ip add 172.16.20.2 255.255.255.0

R2 (config-if)#no shut

R2 (config-if)# ip add 172.16.30.1 255.255.255.0


Static routing on router r1

R1 >en

R1 #config t

R1(config)#ip route <dest. Add> <mask> <gateway>

R1(config)#ip route 172.16.30.0 255.255.255.0 172.16.20.2

Static routing on router r2

R1 >en

R2 #config t

R2(config)#ip route <dest. Add> <mask> <gateway>

R2(config)#ip route 172.16.30.0 255.255.255.0 172.16.20.1

To disable static routing on r1

R1 #config t

R1 (config) # no ip route 172.16.30.0 255.255.255.0 172.16.20.2

Dynamic routing – It can be defined as the phenomena in which the routing protocols are assigned the job of finding the path to route the packets and update routing tables.

Routing protocol – It is defines the set of rules used by router when it communicates routing information between neighbours.

Two types of routing protocols

1. Interior gateway protocols 2. Exterior gateway protocols

Note – the major difference between static and dynamic is that we get redundancy in dynamic routing because we publish our own self interface network so that any network can reach in multiple ways.

Administrative Distance – it is used to rate the trustworthiness of routing information received on a router. Its range is between 0- 255.

If router receives two updates listing the same remote network the first thing the router checks is the AD.

Note- lower AD is preferred.

If two protocols have same AD then router uses metrics such as hop count, bandwidth, cost delay, load and reliability, to find best to route the packets to connected network.

Hop – the movement of a packet between any two network nodes.

Hop count – A routing metric that calculates the distance between a source and destination based on the number of routers in the path RIP employs hop count as its sole metric.

Bandwidth – The gap between the highest and lowest frequencies employed by network signals.

Cost – it is an arbitrary value, based on hop count, bandwidth or another calculation that is typically assigned by a network administrator and used by routing protocol to compare different routes through an internetwork.

Delay- the time elapsed between a senders initiation of a transaction and first response they receive the time needed to move a packet from its source to its destination over a path.

Load – Amount of data on the link.

Classes of routing protocols

1. Distance vector2. Link state 3. Hybrid

Distance vector – This protocols find the best path to a remote network by judging distance. The route with the least number of hops to the network is determined to be the best route.

RIP and EIGRP – classfull

Link state – It is called shortest path first protocols. Router create 3 separate tables.

1. It keeps track of directly attached neighbour.2. Determines the topology of entire internetwork.3. One is used as routing table.

1. OSPF and IS-IS - classless OSPF – It is an IP routing protocol that is completely link state. It sends updates containing the state of their own links to all other routers on network.

Hybrid – This protocol use aspects of both distance vector and link state for eg. EIGRP

Interior Gateway Protocols – It is used to route the packets inside an autonomous system (independent network system).

Protocols are

RIP – Routing Information Protocol.

OSPF – Open shortest path First

IGRP – Interior Gateway Routing Protocol

EIGRP – Enhanced Interior Gateway Routing Protocol

IS-IS – Intermediate system to intermediate system.

Exterior Routing Protocol – Protocols that communicate between two or more autonomous system.

Two exterior Routing Protocols are

EGP – Exterior Gateway Protocol

BGP – Border Gateway Protocol

Configure router A

R1 # config t

R1 (config) # router rip

R1 (config-router) # network 172.16.20.0


R1 (config-router) # no shut

Configure router B

R2 # config t

R2 (config) # router rip



R2 (config-router) # no shut

Default Routing – We use default routing to send packets with a remote destination network not in routing table to the next hop router.

To configure a default route, we use wild card in the network address and mask location

To configure default routing of r1

R1# config t

R1(config)# ip route 0.0.0.0 0.0.0.0 172.16.20.2

To configure default routing of r2

R2# config t

R2(config)# ip route 0.0.0.0 0.0.0.0 172.16.20.1

Note – Max 2 default route is pointed in a single network.

RIP – Routing Information Protocol

It manages the exchange of routing table information among router to exchange their routing tables at a predefined interval.

RIP uses hop count to determine the best way to remote network.

Max. Allowable hop count of 15 by default

Efficient for small network.

RIP has 2 versions

RIP version 1

RIP version2

RIP version1 – It uses only classful routing which means that all devices in network must use same subnet mask. It does not send updates with subnet mask.

RIP version 2 – It sends subnet mask information with the route updates. It is classless routing.

Note – Both uses same administrative distance 120.

RIP timers

Route update timer – sets the interval (30 sec) between periodic routing updates in which the router sends a complete copy of its routing table out all neighbors.

Route invalid timers – determines the length of time that must elapse (180 sec) before a router determines that a route has become invalid.

Hold down timer – Sets the amount of time during which routing information is suppressed

Route flash timer – Sets the time between a route becoming invalid and its removal from routing table (240 sec).

Administrative Distance

Static route 1

RIP 1 & 2 120

Eigrp 90/170(internal / external)

IGRP 100

OSPF 110

Unknown 255

Configure router 1 dynamic

R1 # config t

R1 (config)# router rip

R1(config)# network 172.16.20.0


R1 (config) # no auto-summary

To configure router 2

R2 # config t




R2 (config) # no auto-summary

RIP version 2

Configure dynamic routing on router A

R1 # config t


R1(config-router) # version 2

R1(config-router)# network 172.16.1.0


R1 (config-router) # no auto-summary

Configure dynamic routing on router B

R2 # config t


R2(config-router)# version 2




Configure dynamic routing on router C

R3 # config t


R3(config-router)# version 2




IGRP – Interior Gateway Routing Protocol

It is a cisco- proprietary distance vector routing protocol. Support cisco routers only at both ends. Uses bandwidth and delay for determining best route to an internetwork. Needs autonomous system (AS) for configuration

Dynamic routing of router A

R1 (config) # router igrp 10



Dynamic routing of router B




Dynamic routing of router A




R1 (config)# router igrp 20

R1 (config-router)# network 172.16.30.0


Dynamic routing of router B




Dynamic routing of router C




EIGRP – Enhanced Interior Gateway Routing Protocol

It is classless, enhanced distance vector protocol that gives us a real edge.

It uses the concept of autonomous system.

It works on path calculation based on five metrics.

Bandwidth

Load

Delay

Reliability

MTU – Maximum Transmission Unit

Autonomous System – A group of networks under mutual administration that share the same routing methodology. As are sub-divided by areas and must be assigned an individual 16 bit number given by IANA.

Note – The best point in EIGRP is that when any changes occur in any network then it releases its update.

EIGRP uses following table for route discovery.

Neighbour Table – stores the condition of directly connected neighbour and new neighbour.

Topology table – store the advertisements of destinations by the neighbour which consists of destination address the neighbour that are linked with destination.

Route Table – router that helps to make the routing decisions are stored in route table.

Successors – path with the best metric as compared to all other paths.

Feasible Successors – it is a backup route and is stored in topology table. A successor route is stored in topology table and is copied and placed in routing table.

Troubleshooting commands

Show ip route – shows the entire routing table

Show ip route eigrp – shows only eigrp entries

Show ip eigrp neighbour – show all eigrp neighbour

Show ip eigrp topology – show entries in eigrp in topology

Debug eigrp packet – hello packets sent / receive between adjacent router.

Debug ip eigrp notification – show eigrp changes and updates as they occur in your network.

Features of EIGRP

Supports for multiple autonomous system numbers on a single router.

Support VLSM

Sends subnet mask information in routing updates

Supports discontinuous network

Supports summarization of router connected to reduce size of routing table.

OSPF – Open Shortest Path First

It is a link state routing protocol. Updates the routing table only when network changes occur.

Its work is based upon area system. All areas are connected to area 0 which is backbone area. In each area there are 50 router supported.

Features

Consists of areas and autonomous system

Minimizes routing update traffic allows scalability

Supports VLSM/CIDR

Has unlimited hop count

Allows multi-vendor deployment

OSPF hierarchy design

Autonomous system – Sets the networks grouped together with a common administrative control

Areas – A logical, rather than physical sets of segments along with their attached devices. Areas are commonly connected to other using routers to single autonomous system.

Backbone Area – The basic portion of network that provides the primary path for traffic sent to and initiated from the other network.

Area border router – (ABR) – An OSPF router that is located on border of one or more OSPF areas. ABR’s are used to connect OSPF areas to OSPF backbone.

Stub Area – An OSPF area carrying a default route, intra area routes and inter area routes but no external routes. It does not have multiple exit point only single area border router is connected to stub area.

ASBR- Autonomous system boundary router

An area border router placed between an OSPF autonomous system and non-OSPF network that operates both OSPF and an additional routing protocol such as RIP.

OSPF Terminology

Link – A router that is connected to the network and uses OSPF as its routing protocol is defined as link.

Router ID – The IP address that identifies the router is called router ID.

Neighbour - When two or more router are connected physically with the help of an interface such as a serial or fast ethernet are termed as neighbour.

Adjacency – it is a relationship between two OSPF router that permit the direct exchange of route updates.

Hello Protocol – The protocols that are sent by the routers to discover and preserves the relationship with the neighbours. The protocols along with link state advertisement (LSA) update the topological database.

Neighbourship Database – It is a list of all OSPF routers for which hello packets have been sent.

A variety of details including the router ID and state are maintained on each router in this database.

Topological database – It contains information from the entire link state advertisement packet that have been received for an area. Router uses the information from the topology database as input into algorithm that computes the shortest path.

Designated Router – These are decided hello protocols when two or more OSPF router attempt to access the same multi-access networks. These networks have more than one recipient. It reduces the number of adjacencies in multi-access network and reduces routing protocol traffic and topological size.

BDR – Backup Designated Router

The router used as an alternative for DR.

Broadcast (multi-access) – It allows multi devices to connect to same network as well as provide a broadcast ability in which a single packet is delivered to all nodes on the network.

Non-broadcast multi-access – These networks allow for multi-access but have no broadcast ability. So these networks require special OSPF configuration to function properly and neighbour relationship must be defined.

Point to point – When two routers are connected directly using a serial cable and packets are terminated using a single communication path.

Point to multi-point – When a router is connected to multiple routers using a single interface.

Configure an OSPF

Syntax

Router ospf process_id

Network ip_add wildcard mask

Area area_#

Process_id – provides a unique identification to OSPF processes running on router.

IP _address – specifies the IP address of OSPF area interface.

Wildcard mask – provides specification to router regarding part of address that should match.

Area – Specifies area where the address on the router belongs

Router R1

R1 (config) # router ospf1

R1 (config-router) # network 192.168.10.64 0.0.0.7 area 0


Router R2




R2 (config-router) # 10.255.255.0 0.0.0.3 area 0

Router R3




Router R1




Router R2

R2(config) # router ospf20



Or

Router1

R1 (config) # router ospf 20


Router 2

R2 (config) # router ospf 20


Wildcards: Indicates that the corresponding octet in the network must match exactly 255 indicates that you don’t care what the corresponding octet is in the network number.

Just the opposite of subnet mask

Block Size – 0, 3, 7, 15, 31, 63

Loopback – These are logical interface which are virtual. It ensures that an interface is always active for ospf processes.

Advantages of loopback

Used for diagnostic purposes

Highest IP address on router will become that router’s RID which is used to advertise the routes as well as elect DR and BDR.

Configuration

R1 (config) # int loopback 0

R1 (config-if) # ip add 192.168.90.1 255.255.255.0


R1 (config-if) # ip add 192.168.80.1 255.255.255.0


R1 (config-if) # ip add 192.168.70.1 255.255.255.0

R1 (config-if ) # no shut

OSPF

AD – Administrative Distance 110

DR – Designated Router

Any network changes in area are maintained by DR.

Access-list – A set of test conditions kept by routers that determines interesting traffic to and from the router for various services on the network.

Or

It is a set of commands, which are grouped together to filter traffic that enters or leaves an interface.

It allows the administrator to deny or permit traffic that enters the interface.

Functions of ACL

1. Reduce network traffic and increase the network performance.2. Control the flow of traffic in the network by limiting the routing updates.3. Provides security for network access.4. Make decision about the type of network to be forward or restricted on an interface.

Inbound list – Filters the traffic as it enters the interface.

Outbound access list – Filters the traffic before it leaves the interface.

Types of ACL

1. Standard ACL2. Extended ACL 3. Named ACL

Standard Access List – These use only the source IP address in an IP packet no destination address. It basically permits or deny suite of protocols.

Extended Access List – These use source destination IP addresses to filter the packets. This gives extended access list the ability to make much more granular decision which controlling traffic.

Names Access List – these are either standard or extended but they are referred by names.

Standard Access List

Access List – are differentiated using a number.

1-99 IP standard access list

100-199 IP extended access list

1100-1199 extended 48 bit MAC address list

1300-1999 IP standard access list (expanded range)

200-299 protocol type code access list

2000-2699 IP extended access list (expanded list)

700-799 48 bit MAC address access

Syntax – standard access list

Deny – specify packets to reject

Permit – specify packets to forward

Remark – access list entry comment

R1 (config)#access-list 10 deny 172.16.10.0 0.0.0.255

R1 (config) # access-list 20 permit <source> <wildcard mask>

Log into the router

Switch to privilege mode

Configuration mode

Router > en

Router (config) # hostname r2

R2 (config) # access-list1 deny 192.168.10.10 0.0.0.255

R2 (config) # access-list1 permit 192.168.10.10 0.0.0.255

R2 (config) # interface ethernet 0/0

R2 (config-if) # ip access-group 1

R2 (config-if) # exit

R2 (config) #

Syntax

Access-list 1-99 permit/deny source-address wildcard

199.1.11.0 Cannot access network 199.1.12.0 but can still access by the rest of network

# Config t

# access-list 10 deny 199.1.11.0 0.0.0.255

# access-list 10 permit any any

# Int fa0/0

# Ip access-group 10 out

# 199.1.11.12.0 but can still access by the rest of network and host

# Config t

# access-list 10 deny 199.1.11.2 0.0.0.0

# access-list 10 permit any any

# int fa0/0

# ip access-group 10 out

R2 # config t

R2 (config) # access-list 10 permit any any

R2 (config) # interface ethernet 0

R2 (config-if)# access-group 10 out

Extended ACL

Syntax

Access-list <100-199> permit/deny

Ip_protocol source-address source-wildcard log

Router r2

R2 (config) # access-list 131 deny tcp 192.168.70.10 255.255.255.0 202.197.47.1 255.255.255.0

R2 (config) # access-list 131 deny tcp 192.168.50.10 255.255.255.0 202.197.47.1 255.255.255.0

R2 (config) # int s0/1

R2 (config) # ip access-group 131 out

Switching

Switch – It is a device responsible for multiple functions such as filtering flooding and sending frames. It works using destination address of individual frames. Operates at data link layer.

Features

It creates private dedicated collision domain.

Provides independent bandwidth on each port.

Layer 2 switching provides

1. Hardware base bridging 2. Wire speed 3. Low latency low cost

Bridging Vs switching

1. Bridges are software based – switches are hardware 2. Switch is a multi port bridge 3. Both forward layer 2 broadcast

4. Both learn MAC address by examining the source address of each frame received.

Functions of switch at layer

Address learning – they remember the source hardware address of each frame received on interface and enter this information into MAC data called forward/filter table.

Forward/filter decision – When a frame is received on interface the switch looks at the destination hardware address and finds exit interface in MAC address. The frame is only forwarded out the specified destination port.

Loop avoidance – If multiple connections between switches are created for redundancy purposes, network loops can occur STP [spanning tree protocol] is used to stop network loops while still permitting redundancy.

WAN Process

WAN connection types

1. Dedicated line – ISDN These are point to point dedicated connection. A leased line is a pre established WAN communication path that goes from customer premises equipment through DCE switch then over to CPE of remote site.

2. Circuit switching – telephone Used with dial-up networks such as PPP and ISDN. Passes data but needs to set up the connection first.

3. Packet-switching – frame relayDividing a continuous of data into small unit’s packets enables data from multiple devices on network to share communication channel simultaneously but also requires the use of precise routing information.

4. Cell switching – ATM In ATM networking the basic unit data for switching and multiplexing. Cells have a defined of 53 bytes including a 5 byte header that defines the cells data stream and 48 bytes of payload.

ISDN – Integrated service digital network

It is a set of digital services that transmit voice and over existing phone line at a high speed (64 kbps).

Features

1. Speed 2. Multiple device support – allows multiple device on single line.3. Inexpensive

ISDN supports two type of connection

1. BRI – Basic Rate Interface 2. PRI – Primary Rate Interface

BRI – It consists of two channels and one channel.

B channel – 64 kbps

D channel – 16 kbps

PRI – It consists of 23 B channel and one D channel B channel – 64 kbps D channel -

Used in North United States

23 B channels

1 D channel

Total bit rate 1.544 mbps

Used in Europe and Australia

30 B channels

1 D channel

Total bit rate 2.048 mbps

Frame-relay

It is a protocol used connecting devices on WAN. Operate at data link layer providing a connection-oriented network. A DLCI data link connection identifier is used for finding a communication path between source and destination nodes.

Frame relay is configured on serial interface. Its default speed is up to 56 kbps.

Component of frame relay

Data terminal equipment – connects a computer to WAN with the help of DCE DTE is end user equipment such as router or computer.

A device where a communication path begins or ends is called DTE.

Data communication equipment (DCE) – creates a physical connection between over a network. It is responsible for forwarding traffic and transferring data between computers eg. Modem

Important Terms

DLCI – Data Link connection identifier

It is a frame relay header which is used to map router. It is a 10 bit number.

CIR – Committed information Rate

The maximum bandwidth of data guaranteed to be delivered by an ISP to customer.

Note – If any organization or customer wants more bandwidth apart from default whatever conjunction remains in network he needs to pay more to ISP.

LMI – Local management Interface

It is clocking and switching signalling standard between services provides and customer end devices.

Or

It is signalling standard used between your router and the first frame relay switch it’s connected to.

It allows for passing information about the operation and status of virtual circuit between ISP and customer device.

Virtual circuit

A logical circuit device to assure reliable communication between two devices in a network. These circuits are what link together the thousands of devices connected to provide cloud.

Router R1

R1 (config) # int s0

R1 (config) # encapsulation frame-relay


R1 (config) # int s0.1 point-to-point

R1 (config-subif) # ip add 192.168.1.1 255.255.255.0

R1 (config-subif) # frame-relay interface dlci 102


R1 (config-subif) # exit

R1 # wr

Router R2

R2 (config) # int s1

R2 (config-if) # encapsulation frame-relay


R1 (config) # int s1.1 point-to-point

R1 (config-subif) # ip add 192.168.1.2 255.255.255.0



R1 (config-subif) # exit

R1 # wr

NAT – Network Address Translation

It is a process of converting private of IP address into public IP address. It is a standard that allows LAN to operate with a single IP Address when connected to internet. It hides the IP address of private network.

Types of NAT

1. Static NAT 2. Dynamic NAT 3. NAT overload PAT

Static NAT – It allows one to one mapping between local and global addresses.

Dynamic NAT – It allows pool of public IP address to convert in many private addresses.

PAT – Port Address Translation

This process allows a single IP address to represent multiple resources by altering the source TCP or port number.

Terminology

Inside Local – name of inside source address before translation.

Outside Local – name of destination host before translation.

Inside global – name of inside host after translation.

Outside global – name of outside host after translation.

Configuration commands

Access list – It defines standard IP access list for inside network.

IP NAT pool – It defines an IP NAT pool for inside network.

IP NAT inside source list pool – Maps the access list to IP NAT pool.

IP NAT outside source pool – It defines mapping between access list and outside local pool.

IP NAT inside source static – It defines the addresses when using static address translation for local addresses.

IP NAT [ inside 1 outside] – It enables NAT on at least one inside and one outside interface.

IP NAT inside destination list pool – It defines mapping between the access list and real host pool.

Static NAT configuration

# ip nat inside source local_ip global_ip

# int e0

# ip nat inside

# exit

NAT_router # configure terminal

NAT router (config) # ip nat inside source static 192.168.50.10

# interface serial 0/1

# ip nat inside

# exit

NAT_router (config) # int serial 0/0

(config-if) # ip nat outside

(config-if) # exit

Nat (config) # ip nat source static 10.1.1.1 170.46.2.2

Nat (config) # int e0

Nat (config-if) # ip add 10.1.1.10 255.255.255.0

Nat (config-if) # ip nat inside

Nat (config-if) # exit

Nat (config) # int s0

Nat (config-if) # ip add 170.46.2.1 255.255.255.0

Nat (config-if) # ip nat outside

Nat (config- if) # exit

Dynamic configuration

Syntax

# ip nat pool pool_name start_ip end_ip

# ip nat inside source start_ip end_ip

# int e0

# ip nat inside

#exit

R2 (config) # ip nat pool airtel 170.16.13.19 170.16.13.32 255.255.255.0

R2 (config) # ip nat inside source192.168.1.0 192.168.1.254

R2 (config) #int e0

R2 (config-if) #ip nat inside source list 1

R2 (config-if) #exit

R2 (config)# access-list 1 permit 192.168.1.0 0.0.0.255

PAT – Port Address Translation

Configuration

Note – To configure PAT delete dynamic NAT configuration using clear command

Nat (config) # clear ip Nat translation

Nat (config) # no ip nat pool globalnet 172.168.50.10 172.168.50.50 netmask 255.255.255.0

Nat (config) # ip nat pool patpool 172.168.50.100 172.168.50.100 netmask 255.255.255.0

Nat (config) # access-list 1 permit 10.0.0.0 0.0.0.255



Nat (config) # ip nat inside source list 1 pool patpool overload

VLAN – Virtual Local Area Network

It is a logical LAN. It defines a

a logical subnet is a group switch ports assigned to same VLAN regardless of their physical location in a switched network.

VLAN is a group of network devices that behave as they are connected to a single network segment.

Devices in single VLAN can share resources and bandwidth.

This reduces the traffic on network but every

needs to have separate network number.

Features of VLAN

1. Broadcast control – we can create individual networks and direct the messages or data to the host connected to the specific VLAN.

2. Security – It allows you to create and regulate independent networks or broadcast group which control ports to prevent unauthorized access of network.

3. Flexibility and scalability – it allows us to construct groups or networks connected to a switch or group of switches and we can modify the group by adding or deleting user.

Types of VLAN

End to end VLAN – members can reside on different switches. They are assigned to VLAN based on functions or workgroup rather than location.

Local VLAN – Host are assigned to VLAN based on their location.

VLAN membership can be assigned through

1. Static 2. Dynamic

Static VLAN – manually configured port by port.

Administrator decides which broadcast domain the host shall be connected and also to which VLAN these hosts shall belong.

Note- IP address of host should belong to network address of its respective VLAN.

Dynamic VLAN – Switches are assigned to VLAN automatically. It is based on number of host connected to switch. In this administrator needs to store the devices MAC address through VMPS- VLAN management policy server that maps MAC to VLAN.

Static VLAN

Switch > en

Switch # config t

Switch (config) # int fa0/1

Switch (config-if) # switch_port mode access

Switch (config-if) # switch_port access VLAN 12

Dynamic VLAN

Switch > en

Switch #config t

Switch (config) # int fa0/1

Switch (config-if) # switch_port mode access

Switch (config-if) # switch_port access VLAN dynamic

Switch (config-if) # vmps server ip address.

Trunking

Trunk links – it is a link of 100 or 1000 mbps point to point link between two switches it carries the traffic of multiple VLANs.

There are two options for trunking VLAN traffic between switches

1. ISL

2. 802.1 Q

ISL –inter switch link

It is a way of explicitly tagging VLAN to be multiplexed over a trunk link through external encapsulation. It allows the switch to identify VLAN membership of a frame over the trunk link.

IEEE 802.1 Q (supports ethernet & token ring)

It is a standard method of frame tagging. It inserts a field into the frame immediately after source MAC to identify VLAN.

VTP – VLAN trunking protocol

These are used to manage all configured VLANs across a switch. It allows to add delete and rename VLAN information that propagates across all switches configured in VTP domain.

Features of VTP

1. Consistent VLAN configuration across all switches in network.2. Supports ethernet ATM or FDDI networks 3. Accurate tracking and monitoring of VLANs 4. Dynamic reporting of added VLAN to all switch in a VTP domain.5. Plug and play VLAN adding.

VTP modes

Switches support one of three VTP

1. Client 2. Server3. Transparent

1. Client Mode – Switches receive information from VTP servers but they also send and receive updates. They cannot create change or delete VLAN.

2. Server Mode – This is default mode for all catalyst switches. It need at least one server in VTP domain switch can create add or delete VLAN in VTP domain.

3. Transparent – Switches don’t participate in VTP domain or share its VLAN database but they still forward VTP advertisement s through any configured trunk links. They create modify and delete VLAN and keep their own database.

VTP pruning

It ensures that there is no VLAN traffic sent across a trunk link which does not participate in VLAN network. It pressure bandwidth by configuring it to reduce the amount of broadcast, multicast and unicast packet.

VTP configuration

Switch( config) # vtp mode server

Switch (config) # vtp domain domain_name

Trunk link configuration

Ports can become trunk through static and dynamic registration using DTP (dynamic trunking protocol)

Switch modes

1. Access – The port is user a port in a single VLAN.2. Trunk – The port negotiates trunking with the port on the other end of link.3. Non-negotiate – The port is a trunk and does not do DTP negotiation with other side of link.4. Dynamic Desirable – Actively negotiates trunking with other side of the link. It becomes a trunk

dynamic desirable or dynamic auto mode.5. Dynamic Auto – Passively waits to be contracted by the other switch. It becomes a trunk if other

end is set to trunk or dynamic desirable mode.

Configuration ISL Trunks

To configure an ISL trunk

Switch (config-if) # trunk on

Trunk has 5 option

1. ON 2. OFF 3. Auto

4. Desirable 5. Non-negotiates

Configuration VLAN

Switch (config) #VLAN 10

Switch (config-vlan) # name sales.

To modify name

Switch (config) # vlan 10

Switch (config-vlan) # name sales_group 10

To add port

Switch (config-if) # switch_port access vlan 10

Verification commands

Show vtp status – to verify vtp configuration

Show interface gigabit ethernet 0/2 – switch verify trunks

Show vlan – verify vlan

Show spanning- tree vlan 10 – verify stp configuration

THE INTERFAZE= = EXCELLENCE IN IT/CISCO TECHNOLOGY = =

www.howtonetwork.net

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Name ___________________________________________________________ Mob. No._____________________________________

E-Mail ID_________________________________________________________Contact No.___________________________________

Academic Credential (with Stream) BE(IT) / BE(CS)/ BE(EC)/ BE(E & Ex) Year/Semester

BCA/ MCA/ BSc(IT)/ MSc(IT)

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

1. Do you have any knowledge of Internetworking Technologies such as CISCO, Juniper, AVAYA, NORTEL, Check Points? If yes, Please specify.

________________________________________________________________________________________________________________

2. Do you know the degree of importance if you have these vendor specific International Certifications additional to college degree?

________________________________________________________________________________________________________________

3. Please mark under mention Vendor Specific Certification, if knows about that: apologies

Professional Level

(a) CCNP (Routing & Switching) (b) CCNP(Security)/ CCSP

(c) CCNP (Voice)/CCVP (d) CCNP (Service Provider)/ CCIP

(e) Check Point Engineer/ Professional

Expert Level

(a) CCIE (Cisco Certified Internet Expert) Routing & Switching(b) CCIE (Cisco Certified Internet Expert) Security(c) CCIE (Cisco Certified Internet Expert) Voice over Internet Protocol

(d) CCIE (Cisco Certified Internet Expert) Internet Service Provider(e) CCIE (Cisco Certified Internet Expert) Wireless(f) CCIE (Cisco Certified Internet Expert) Storage Area Network

Specialization

(a) Firewall Specialist (PIX/ASA/Juniper Netscreen/ Fortigate)(b) Identity Management Specialist (AAA)(c) Virtual Private Network (IP Sec, GRE/GRE over IP Sec, GET, DM VPN, Remote VPN, SSL(d) Advanced BGP & MPLS(e) VMware(f) Sunsolaries & Veritas(g) Ethical Hacking(h) IPS/IDS

Few basic term which IT/CS/EC Students must know. Please try to recall your memory and try following questions :

4. You know the concept of TCP/UDP and all protocols comes under Internet Protocol Stack. Which is the fast protocol, TCP or UDP and why?

____________________________________________________________________________________________________________________

5. IP Address may be defined as unique identity of the host. Now 224.0.0.10 is also IP Address. Can it be a unique identity of the host? Specify the class of IP Address mentioned in this question.

___________________________________________________________________________________________________________________

6. Expend the following :

(a) OSI , ISO, IOS (b) ICMP/IGMP

(c) CSMA CD/ CA (e) VLSM/CIDR

(f) IANA (g) Internet

(i) GRE (j) DNS

(k) FORTRAN/ REGEX (l) BGP/MPLS

6. Write the port number of following protocols and specify that they comes under TCP or UDP:-

(a) FTP - (b) HTTP - (c) NTP –

(d) DNS - (e) RADIUS - (e) RIP –

(f) Telnet - (g) SSL- (h) HTTPS-

(i) BGP –

7. Write down OSI Layers and arrange under mention protocol/ Devices in order of OSI Layer.

Router, Hub, HTTP, TCP, UTP Cat6 Cable, IP, Switch, L3 Switch, Spanning Tree Protocol, UDP, Power Point,

8. Fill in the balnks :

a) Protocol used to access web page from Web server with encryption _____________________

b) Protocol used to down load/upload files from server_________________________________

c) “C” language does not have its own commands to write program. It has to depend on ______________

d) Basic difference between symmetric and asymmetric encryption is -______________________________

e) One computing device with limited memory and Storage Capacity runs multiple task of different nature and multiple policies may be define for each context. The concept is called_____________________________ It’s very cost effective.

f) Operating System used to manage LAN and WAN are called __________________ & _______________ respectively.

9. Select the Routing Protocol : IPX, OSPF, Appletalks, BGP, SPX, EIGRP

10. We use Regular Expressions in computer program to obtain desired output. Interpret following Regular Expression :-

(a) \\ (b) * (c) *.ppt

11. Who is Governor of Madhyapradesh ?

12. Who won Vimbledon championship in Female ?

13. What are the top News stories today ?

14. List WAN Technologies which you knows ?

15. What is MAC Address ? MAC Address function on which layer of OSI ?

16. What is IP Address ? IP Address function on which layer of OSI ?

17. What is the difference between Astronauts and Cosmonauts?

18. Explain the function of RADAR? What is MTI and Doppler Effect?

19. Why you can see the sparkles of firecracker much before it’s sound ?

20. What is the deference between Virus and Worms?

Static and Dynamic NAT

Both static and dynamic NAT require that enough public addresses are available to satisfy the total number of simultaneous user sessions.

Static NATStatic NAT also called inbound mapping, is the process of mapping an unregistered IP address to a registered IP address on a one-to-one basis. The unregistered or mapped IP address is assigned with the same registered IP address each time the request comes through. This process is particularly useful for web servers or hosts that must have a consistent address that is accessible from the Internet.

Simply, Static NAT enables a PC on a stub domain to maintain an assigned IP address when communicating with other devices outside its network or the Internet.

Static NAT configuration commands example:

R1#config t

R1(config)#ip nat inside source static 10.10.10.2 212.165.200.123

R1(config)#interface fa0/0 10.10.10.1 255.255.255.0

R1(config)#ip nat inside

R1(config)#interface se0/0 192.168.1.1 255.255.255.0

R1(config)#ip nat outside

The above configuration creates a permanent entry in the NAT table as long as the configuration is present and enables both inside and outside hosts to initiate a connection.

All you need to do in static NAT configuration is to define the addresses to translate and then configure NAT on the right interfaces. Packets arriving on an inside interface from the identified IP addresses are subject to translation. Packets arriving on an outside interface addressed to the identified IP address are subject to translation.

Dynamic NATUnlike static NAT that provides a permanent mapping between an internal address and a specific public address, dynamic NAT maps private IP addresses to public addresses. Dynamic NAT uses a pool of public addresses and assigns them on a first-come, first-served basis. When a host with a private IP address requests access to the Internet, dynamic NAT chooses an IP address from the pool that is not already in use by another host. Dynamic NAT is useful when fewer addresses are available than the actual number of hosts to be translated.

Dynamic NAT configuration commands example:

R1#config t

R1(config)#ip nat-pool 179.9.8.80 179.9.8.95 netmask 255.255.255.0

R1 (config #ip nat inside source list 1 pool nat-pool1

R1 (config)#interface fa0/0 10.10.10.1 255.255.255.0

R1(config)#ip nat inside

R1(config)#interface se0/0

R1(config)#ip address 192.168.1.1 255.255.255.0

R1(config)#ip nat outside

R1(config)#access-list 1 permit 10.10.10.0 0.0.0.255

While static NAT provides a permanent mapping between an internal address and a specific public address, dynamic NAT maps private IP addresses to public addresses. These public IP addresses come from a NAT pool.

Note:

When configuring dynamic NAT, you need an ACL to permit only those addresses that are to be translated. Remember, you have to add an implicit "deny all" at the end of each ACL.

NAT Overload or PAT

NAT overload sometimes called PAT (Port Address Translation) maps multiple unregistered or private IP addresses to a single registered or public IP address by using different ports. This is what most home broadband routers do. Your ISP assigns an IP address to your router, but you find out that all the computers in the house could connect to the Internet at the same time.

PAT uses unique source port numbers on the inside global IP address to distinguish between translations

When a client logs on the Internet, the NAT router assigns a port number to its source address. NAT overload or PAT ensures that clients use a different TCP port number for each client session with a server on the Internet. When the server response, the client router routes the packet based on the source port number, which had become the destination port number. This process also validates that the incoming packets were requested, thus adding a degree of security to the session

NAT Overload Table

Looking at the figure above, NAT overload or PAT used unique source port numbers on the inside global IP address to distinguish between translations. As NAT processes each packet, it uses a port number to identify the packet source - 2333 and 1555 in the above figure -.

Inside Local IP Address Inside Global IP Address Outside Global IP Address Outside Local IP Address

10.10.10.2:1555 209.165.200.226:1555 209.165.201.1:80 209.165.201.1:80

10.10.10.3:2333 209.165.200.226:2333 209.165.202.129:80 209.165.202.129:80

* The source address (SA) is the inside local IP address with the assigned port number attached.

* The destination address (DA) is the outside local IP address with the service port number attached, in this case port 80: HTTP (Internet).

At the border gateway router (R1), NAT overload changes the SA to the inside global IP address of the client, again with the port number attached. The DA is the same address, but is now referred to as the outside global IP address. When the web server replies, the same path is followed but in reverse.

Documents

IP Configuration