DESIGN AND IMPLEMENT A NETWORK WITH PACKET TRACER IT: Network: Cisco 1 Fall 2013

Last few weeks, we…

¨  … looked at subnetting IPv4 network addresses.

¨  … designed a subnetting structure based on the number of networks only. ¤ Not terribly efficient

¨  … designed a subnetting structure based on the number of hosts on each network. ¤ VLSM

Let’s put it all together

¨  Build a network – what do we need? ¤ Server(s)? ¤ Workstation(s)? ¤ What else?

¨  Suppose we have 2 locations ¤ HQ here in Green Bay ¤ Branch office in Omaha

¨  Let’s sketch it out…

My list

¨  Workstations and Servers “in an appropriate number”

¨  Switch for each physical LAN ¤  If need more than one switch on a LAN that’s fine

¨  Tie our networks together ¤  Routers – one per network?

n  Assuming router has two interfaces ¤ Cables

n  Ethernet – straight-through and cross-over n  WAN/Serial for between routers

Look at Lab from last week

¨  How many routers?

¨  How tie routers together?

¨  What “makes” a LAN?

¨  How connect router to LAN?

LAN B800 Hosts

LAN C2,000 Hosts

LAN A6,000 Hosts

LAN D1,000 Hosts

WAN A-B WAN A-C WAN A-D

WAN Links

¨  Plain Old Telephone System (POTS) =up to 56 Kbps

¨  T1=1.544 Mbps ¨  T3=44.736 Mbps (21 T1’s) ¨  ADSL = 16−784 Kbps up; 1−9 Mbps down ¨  Cable modem = 512Kbps − 54Mbps

HQBranch Office

WAN link

Connect to WAN

¨  Old School − Dial-up to POTS è Modem

Connect to WAN Links

¨  DTE (our router) needs to connect to WAN ¨  DCE is “modem-like” device that does the connect

¨  A CSU/DSU is the DCE for connection to T1

DTE/DCE Cable

¨  Used in lab / testing environment to simulate a WAN link

¨  Sort of a “cross-over” for WAN.

¨  One side needs to take role of providing clock signal ¤  Typically done by CSU/DSU

¨  Side with the DCE end sets clock ¤ ONLY done by the side with the DCE!

OK… Let’s implement one…

¨  Need to create LANs ¤  Switch for each LAN

¨  Need to implement Workstations and Servers ¤  For simulation, one WS and one Server per LAN is enough

¨  Need to connect LANs ¤  Routers – one for each LAN

n  Used to connect LAN to Serial WAN

Packet Tracer – Build a LAN

¨  Add Switch

¨  Add Workstation

¨  Add Server

¨  Connect them

Straight-Through Cross-Over

Connect LAN nodes

¨  Workstation to Switch è Straight-through Copper ¤ FastEthernet

¨  Server to Switch è Straight-through Copper ¤ FastEthernet

¨  Router to Switch èStraight-through Copper ¤ FastEthernet 0/0 or FastEthernet 0/1

Packet Tracer: Inter-Connect LANs

¨  Add Router ¨  Add Router Interfaces (most likely needed)

¤ POWER OFF Router

Power

Empty Slot 2-Serial Port Module

PT – Inter-Connect LANs continues

¨  Router to Router è Serial DCE cable ¤ DCE = Data Communication Equipment

n Controls the comm. line (like a Modem of old) ¤ DTE = Data Terminal Equipment

n Actual end-node device (like a PC)

¨  On router, use Serial 0/0/0, Serial 0/0/1, Serial 0/1/0, or Serial 0/1/1

¨  DCE provides clock signal on WAN link ¤ One router on each Serial line must provide clock

Serial DCE

Configure Devices: IP Design

¨  IP network ID: 172.16.0.0 /16

Subnet  Name  

Needed  Size  

Allocated  Size   Address   Mask   Dec  Mask   Assignable  Range  

LAN  A   800   1022   172.16.0.0   /22   255.255.252.0   172.16.0.1  –  172.16.3.254  LAN  B   200   254   172.16.4.0   /24   255.255.255.0   172.16.4.1  –  172.16.4.254  WAN   2   2   172.16.5.0   /30   255.255.255.252  172.16.5.1  –  172.16.5.2  

Configure Devices in PT

¨  Workstations and Servers ¤ Statically assign “Appropriate” addresses for that

subnet ¤ Click the Object - Desktop - IP Config

Config Routers in PT

¨  Connection to LAN should be First valid host in that subnet

¨  Connection to other Router should be valid for that subnet (only two choices)

PT Router Config

¨  Click Object - Config - interface

¨  FastEthernet 0/0

IP Config

Activate it

PT Router Serial Config

¨  Click Object - Config - interface

¨  Serial 0/0/0

IP Config

Activate it

Set clock rate on DCE side of connection

Static Routes on the Router

¨  By default, routers only know about the networks they are directly connected to. ¤ Need to “learn” about non-connected networks.

PT- Static Routes

¨  One solution is create a static route to non-connected networks.

¨  Click Object - Config - Static (under Routing)

Remote Network Or 0.0.0.0 for default

Netmask of remote net Or 0.0.0.0 for default

Router that is “closer” to the destination net

Save PT Router Config

¨  Cisco Routers get configuration from startup-config file at boot time

¨  Need to save our settings to that file in NVRAM

¨  Click Object - Settings

Test it

¨  From simulated Workstation, start pinging your default gateway and work progressively further away ¤ Click Object - Desktop - Command prompt

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Summary

¨  We’ve looked at IP addressing ¤ Address; Subnet Mask; Gateway

¨  We’ve looked at Full Octet Subnetting ¨  We’ve looked at Partial Octet Subnetting ¨  We’ve designed a subnetting scheme with a fixed

length subnet mask ¨  We’ve designed a subnetting scheme with a variable

length subnet mask (VLSM) ¨  We’ve talked about applying our plan (assigning

addresses) ¨  Now we are ready to do it (Yay)!