Jan 9, 2015
Tools
Hardware;
- Router
- Switch
- Laptop/PC
- Console cable
- Ethernet Cable (Cat5(e)/Cat6)
Software;
- CIOS
- Packet Tracer
ICONS
What is a Router?
A router is a device that forwards data/voice packets
along networks.
A router is a device that routes network traffic
What is a Switch?
A switch serves as a controller, enabling networked
devices to talk to each other
Managed
Unmanaged
Device and Port/Interface Identification
Exercise 1.
1.
2.
3.
4.
Identify a router
Identify a switch
Identify all interfaces on your router and switch
Identify all cables and connectors.
Exercise 2
1. Install any terminal of your choice (Putty, secureCRT, Teraterm)
2. Configure serial line connection settings
i. Speed = 9600
ii. Data bits = 8
iii. Stop bits = 1
iv. Parity = None
v. Flow Control = XON/XOFF
3. Power on devices.
4. Examine the boot process.
Packet Tracer
The language.
- Computers only understand the language of zeros and ones.
Binary
Understanding IP Addressing
Understanding IP Addressing
IP Address: A logical numeric address that is assigned to every
single computer, printer, switch, router or any other device that is
part of a TCP/IP-based network
Subnet: A separate and identifiable portion of an organization's
network, typically arranged on one floor, building or geographical
location
Subnet Mask: A 32-bit number used to differentiate the network
component of an IP address by dividing the IP address into a
network address and host address
Network Interface Card (NIC): A computer hardware component
that allows a computer to connect to a network
Understanding IP Addressing
DHCP: Dynamic Host Configuration Protocol (DHCP) is a network
protocol that enables a server to automatically assign an IP address
to a computer from a defined range of numbers (i.e., a scope)
configured for a given network
TFTP: Trivial File Transfer Protocol (TFTP) is a simple, lock-step, file
transfer protocol which allows a client to get from or put a file onto
a remote host.
DMARC: The separation point between carrier equipment and CPE.
DNS (Domain Name System)
A system used on the Internet for translating names of network
nodes into addresses.
HTTP (Hypertext Transfer Protocol)
The protocol used by web browsers and web servers to transfer
files, such as text and graphic files.
Understanding IP Addressing
HTTPS (Hypertext Transfer Protocol Secure)
The protocol used by web browsers and web servers to transfer
files, such as text and graphic files securely.
Port Number
A field in a TCP or UDP header that identifies the application that
either sent or should receive the data inside the data segment.
Common ports include: 80, 443, 110, 21, 3389, 25, 5060
RAM (Random-access Memory)
A type of volatile memory that can be read and written by a
microprocessor.
Understanding IP Addressing
NVRAM (Non-Volatile Random-access Memory)
A type of non volatile memory that can be read and written by a
microprocessor and retains information when powered off.
Routing Protocol
A protocol that accomplishes routing through the implementation
of a specific routing algorithm. Examples include the Interior
Gateway Routing Protocol (IGRP), the Open Shortest Path First
(OSPF) protocol, and the Routing Information Protocol (RIP).
Subnetting.
Classful IP Addressing.
Subnetting.
Subnet Mask based on Class
Converting Decimals to Binary .
13
12
11
10
Bits
24
n
2
23
22
21
20
2 raised to
bit value
32
16
8
4
2
1
Actuals
224
240
248
252
254
255
Subnet
Mask
17
16
15
14
27
26
25
128
64
128
192
1
0
1
0
1
0
1
1
Exercise: Convert 171 to binary
n
2
Converting Decimals to Binary .
Converting Decimals to Binary .
Exercise 2.
1.Question 1: Convert
255 from decimal to
binary.
2.Question 2: Convert
187 from decimal to
binary.
3.Question 5: Convert
241 from binary to
decimal.
4. Question 3: Convert
223 from decimal to
binary.
5. Question 4: Convert
240 from decimal to
binary.
Converting Decimals to Binary .
Converting Decimals to Binary .
Cisco Devices/ IOS
Open Systems Interconnection model (OSI)
is a conceptual model that characterizes and
standardizes the internal functions of a
communication system by partitioning it into
abstraction layers.
7.
6.
5.
4.
3.
2.
1.
Application
Presentation
Session
Transport
Network
Data link
Physical
7.
6.
5.
4.
3.
2.
1.
Anyway
Packets
Stupid
Those
Need
Don’t
People
Please Do Not Tell Sales People Anything
Physical (Layer 1)
It provides the hardware means of sending and
receiving data on a carrier, including defining cables,
cards and physical aspects.
e.g RJ45
Please Do Not Tell Sales People Anything
Data Link (Layer 2)
At this layer, data packets are encoded and decoded
into bits. It furnishes transmission protocol knowledge
and management and handles errors in the physical
layer, flow control and frame synchronization.
The data link layer is divided into two sub layers: The Media Access Control (MAC)
layer and the Logical Link Control (LLC) layer. The MAC sub layer controls how a
computer on the network gains access to the data and permission to transmit it. The
LLC layer controls frame synchronization, flow control and error checking.
e.g. PPP, FDDI, ATM, IEEE 802.5/ 802.2, IEEE 802.3/802.2, HDLC
Please Do Not Tell Sales People Anything
Network (Layer 3)
This layer provides switching and routing technologies,
creating logical paths, known as virtual circuits, for
transmitting data from node to node. Routing and
forwarding are functions of this layer, as well as
addressing, internetworking, error handling,
e.g. AppleTalk, IP,
Please Do Not Tell Sales People Anything
Transport (Layer 4)
This layer provides transparent transfer of data
between end systems, or hosts, and is
responsible for end-to-end error recovery and
flow control. It ensures complete data transfer.
e.g SPX, TCP, UDP.
Please Do Not Tell Sales People Anything
Session (Layer 5)
This layer establishes, manages and terminates
connections between applications. The session layer
sets up, coordinates, and terminates conversations,
exchanges, and dialogues between the applications at
each end. It deals with session and connection
coordination.
- e.g. RPC, SQL.
Please Do Not Tell Sales People Anything
Presentation (Layer 6)
This layer provides independence from differences in data
representation by translating from application to network format,
and vice versa. The presentation layer works to transform data into
the form that the application layer can accept. This layer formats
and encrypts data to be sent across a network, providing freedom
from compatibility problems.
TIFF, GIF, JPEG, MPEG, MIDI.
Please Do Not Tell Sales People Anything
Application (Layer 7)
This layer supports application and end-user processes.
Communication partners are identified, quality of service is
identified, user authentication and privacy are considered, and
any constraints on data syntax are identified.
file transfers, e-mail, and other network software services. Telnet
and FTP are applications that exist entirely in the application
e.g. browsers, NFS, SNMP, Telnet, HTTP, FTP
Please Do Not Tell Sales People Anything
3:1
1:1
1:1
2:1
Please Do Not Tell Sales People Anything
Please Do Not Tell Sales People Anything
Please Do Not Tell Sales People Anything
Please Do Not Tell Sales People Anything
Which of the following correctly describe steps in the OSI data encapsulation process?
(Choose two)
A. The transport layer divides a data stream into segments and may add reliability and
flow control information.
B. The data link layer adds physical source and destination addresses and an FCS to
the segment.
C. Packets are created when the network layer encapsulates a frame with source and
destination host addresses and protocol-related control information.
D. Packets are created when the network layer adds Layer 3 addresses and control
information to a segment.
E. The presentation layer translates bits into voltages for transmission across the
physical link.
Please Do Not Tell Sales People Anything
A network administrator is verifying the configuration of a newly
installed host by establishing an FTP connection to a remote
server. What is the highest layer of the protocol stack that the
network administrator is using for this operation?
A. application
B. presentation
C. session
D. transport
E. internet
F. data link
Please Do Not Tell Sales People Anything
A receiving host computes the checksum on a frame and
determines that the frame is damaged. The frame is then
discarded. At which OSI layer did this happen?
A. session
B. network
C. physical
D. data link
E. transport
Please Do Not Tell Sales People Anything
At which layer of the OSI model is RSTP used to
prevent loops?
A. data link
B. network
C. physical
D. transport
Please Do Not Tell Sales People Anything
Please Do Not Tell Sales People Anything
Routers are Computers
Routers are at the Center of every Network
What is a Router?
Main Function
Is to router or
forward packets
destined for local
and remote
network by
determining best
path
What is a Router?
Routers are Computers
CPU
RAM
ROM
Operating system
CPU
RAM
ROM
Flash memory
NVRAM
Cisco Devices/ IOS
CPU
The CPU executes operating system instructions such as
1. System initialization
2. Routing Functions
3. Network interface Control
RAM
Stores information or instructions needed to be executed such as
1.
2.
3.
4.
Operating system (Copied to RAM during bootup)
Running Configuration
IP Routing Tables
ARP Cache (Maps IP addresses to MAC addresses)
ROM
Read only memory is permanent storage. Cisco devices use ROM to store
1. Bootstrap instructions
2. Basic diagnostics software
3. A scaled down version of IOS
Flash Memory
This is non volatile computer memory that can be electronically erased and
reprogrammed. It is used as a permanent storage of the;
1. Operating system (CIOS)
NVRAM
This is also non volatile Random Access Memory which is used to store
1. The start-up configuration file.
The Boot Process
The Boot Process
The Boot Process
The Boot Process
A Cisco router is booting and has just completed the POST
process. It is now ready to find and load an IOS image.
What function does the router perform next?
A. It checks the configuration register
B. It attempts to boot from a TFTP server
C. It loads the first image file in flash memory
D. It inspects the configuration file in NVRAM for boot
instructions
CLI Configuration and Addressing-Basic Router Configuration
User EXEC Mode
The default command mode for the CLI is user EXEC mode. the user EXEC commands
allow you to connect to remote devices, perform basic tests, and list system information.
Router>.
Privileged EXEC Mode
Privileged EXEC mode is password protected, and allows the use of all EXEC mode
commands available on the system.
Router# .
Global Configuration Mode
Global configuration commands generally apply to features that affect the system as a
whole, rather than just one protocol or interface.
Router(config)# .
ROM Monitor Mode, and Setup Mode (ignore)
Basic Router Configuration
When configuring a router, certain basic tasks are
performed. Including the following
1. Name the router.
2. Setting password.
3. Configuring interfaces.
4. Configuring a banner.
5. Saving changes on a router.
6. Verifying basic configuration and router operations.
Appendix 1A
A network administrator needs to allow only one Telnet connection to a router.
Which set of commands will accomplish this task?
A.
access-list 1 permit 192.168.1.0 0.0.0.255
line vty 0 4
login
password cisco
access-class 1
B.
enable password secret
line vty 0
login
password cisco
C. line vty 1
login
password cisco
D. line vty 0 4
login
password cisco
Subnet Mask / # of Host
Routers are at the Center of every Network
Subnet Mask / # of Host
n
2
Subnets =
n
Host = 2 -2
n= # of borrowed bits
Subnet Mask / # of Host
16 hosts < 25 – 2 (we need to borrow 5 bits -> /27)
11 hosts < 24 – 2 (borrow 4 bits -> /28)
5 hosts < 23 – 2 (borrow 3 bits -> /29)
Subnet Mask / # of Host
Convert the following binary to decimal--01101101.
225
109
1101
112
Subnet Mask / # of Host
What address Class does 172.16.33.1/24 belong to?
Class A
Class B
Class C
Class D
Subnet Mask / # of Host
When calculating usable hosts per subnet, the following
formula is used 2^bits - 2. For what reason is two
subtracted? (choose two)
Broadcast
Multicast
Unicast
Network
Subnet Mask / # of Host
Your organization is designing a Wide Area Network. Locations
have varying numbers of hosts. The largest network will have no
more than 55 hosts. What subnet mask accomplishes the goal
and maximizes the number of subnets that may be created?
A: 255.255.255.192
B: /25
C: 255.255.255.224
D: /27
Subnet Mask / # of Host
What are two ways to represent a network mask that would
allow 14 hosts?
A: /14
B: 255.255.255.240
C: 255.255.14.0
D: /28
Subnet Mask / # of Host
Based on 1.1.1.0/24, the IP address would be:
Class A
Class B
Class C
Class D
Subnet Mask / # of Host
How many hosts can be located on a network,
where the IPv4 netmask is 27 bits?
A: 27
B: 30
C: 32
D: 5
Appendix 1B-1
Appendix 1B
Cisco Discovery Protocol
CDP
CDP is primarily used to obtain protocol addresses of direct neighboring devices
and discover the platform of those devices
Command
Router(config)# cdp run
Purpose
Enables CDP on the system.
Router(config)# no cdp run
Disables CDP on the system.
Router(config-if)# cdp enable
Enables CDP on an interface.
Router(config-if)# no cdp enable
Disables CDP on an interface.
Router# show cdp neighbour
Collision & Broadcast domain
A collision domain is, as the name implies, a part of a network where
packet collisions can occur. A collision occurs when two devices send a
packet at the same time on the shared network segment. The packets
collide and both devices must send the packets again, which reduces
network efficiency. HUB and SWITCHES
A broadcast domain is a domain in which a broadcast is forwarded. A
broadcast domain contains all devices that can reach each other at the
data link layer (OSI layer 2) by using broadcast. All ports on a hub or a
switch are by default in the same broadcast domain. All ports on a
router are in the different broadcast domains and routers don't forward
broadcasts from one broadcast domain to another. ROUTER
ICONS
Routing Protocols
RIP
1. Routing protocols enable routers to know where to
forward packets.
2. Information about where a router should send specific
packets are stored in the ROUTING TABLE.
Types of routes.
1. Connected Routes
2. Static Routes
3. Dynamics routes.
Routes
1.Routing tables store information about
other destinations subnets (Subnet
number and subnet mask)
2.They contain the direction which tells the
router what other routers or host to send
packets next(Outgoing interface and nexthop router
Learning Connected Routes
Subnets to which routers interfaces are connected are
called DIRECTLY CONNECTED ROUTES.
A router adds a directly connected route for each interface
that has been configured with an IP address, and its up
and working to its database.
Next Hop
Next Hop
Next Hop
LAB Static Route
Administrative distance
Administrative distance is the feature that routers use in
order to select the best path when there are two or more
different routes to the same destination from two different
routing protocols.
Administrative distance defines the reliability of a routing
protocol.
Each Routing Protocol has its default administrative distance.
Administrative distance
The Default Administrative
distance for RIP is 120
Routing Information Protocol (RIP)
• Routing Protocols exchange routing table information
• Therefore, they learn routing information about IP subnets from their
neighboring routers
• They advertise routing information with their neighboring routers
• If more than one route exist for each subnet, they chose the best route.
(HOW DO THEY DO THIS?)
• If a link fails (topology changes) they react by advertising that some
routes have failed and pick a new currently best route (Convergence)
Routing Information Protocol (RIP)
All routing protocols use a metric
A metric simply determines how good each route is.
Hop-count tells the router how many more routers a
packet has to traverse to get to its destination.
Next Hop
Refer to the exhibit, Host A pings interface S0/0 on router 3,
what is the TTL value for that ping ?
A. 253
B. 252
C. 255
D. 254
Next Hop
Refer to the exhibit, Host A pings interface S0/0 on router 3,
what is the TTL value for that ping ?
Refer to the exhibit. A network administrator attempts to
ping Host2 from Host1 and receives the results that are shown.
What is a possible problem?
A. The link between Host1 and Switch1 is down.
B. TCP/IP is not functioning on Host1
C. The link between Router1 and Router2 is
down.
D. The default gateway on Host1 is incorrect.
E. Interface Fa0/0 on Router1 is shutdown.
F. The link between Switch1 and Router1 is
down.
LAB RIP
Configuring RIP v2 on a Network.
BryPhil#configure terminal
BryPhil(config)#router rip
BryPhil(config-router)#version 2
BryPhil(config-router)#no auto summary
BryPhil(config-router)#network 192.168.1.0
BryPhil(config-router)#network 192.168.2.0
BryPhil(config-router)#network 172.16.1.0
BryPhil(config-router)#network 172.16.2.0
BryPhil(config-router)#end
BryPhil#copy run start
LAB RIP
Review
HINT
A network administrator is verifying the configuration of a
newly installed host by establishing an FTP connection to a
remote server.
What is the highest layer of the protocol stack that the
network administrator is using for this operation?
A. Application
B. Presentation
C. Session
D. Transport
E. Internet
F. Data link
Routing Protocol
OSPF
RIP v1
RIPv2
OSPF
Distance Vector
Classful
Hop-count
Slow Convergence
Distance Vector
Classless
Hop-Count
Slow
Convergence
Less CPU
Less complex
Link-State
Classless
Bandwidth/Cost
Fast Convergence
Less CPU
Less complex
More CPU
More complex
More OSPF
OSPF Cost Calculation and Path Determination
OSPF Cost Calculation and Path Determination
OSPF Cost Calculation and Path Determination
Link-state Routing Process
1. R1; Ethernet network 10.1.0.0/16; Cost 2
2. R1 -> R2; Serial point-to-point network; 10.2.0.0/16; Cost 20
3. R1 -> R3; Serial point-to-point network; 10.3.0.0/16; Cost 5
4. R1 -> R4; Serial point-to-point network; 10.4.0.0/16; Cost 20
Routers in other areas learn that
this route is down, but this is done
with a type of LSP that does not
cause them to rerun their SPF
algorithm. Routers in other areas
can update their routing tables
directly
Route source - Identifies how the route was learned.
Destination network - Identifies the address of the remote network.
Administrative distance - Identifies the trustworthiness of the route source.
Metric - Identifies the value assigned to reach the remote network. Lower values indicate preferred routes.
Next hop - Identifies the IPv4 address of the next router to forward the packet to.
Route timestamp - Identifies from when the route was last heard.
Outgoing interface - Identifies the exit interface to use to forward a packet toward the final destination.
Router(config)# router ospf process_ID
Router(config-router)# network IP_address wildcard_mask area_#
R4(config)#router ospf 4
R4(config-router)#network X.X.X.X xxx.xxx.xxx.xxx area 0
R4(config-router)#network X.X.X.X xxx.xxx.xxx.xxx area 0
R4(config-router)#
X.X.X.X = IP Address
xxx.xxx.xxx.xxx = wild card mask