33597689 Ccna Quick Revision Notes

8/19/2019 33597689 Ccna Quick Revision Notes

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Quick Notes

Standard Access Lists

1 - 99 or 1300 - 1999 Standard Access List (Looks at the source IP) place close to destination

Stop the Accounting users from accessing the ! ser"er attached to La# $ router #ut allo% all other users access to the LA&'

RouterB#config tRouterB(config)#access-list 10 deny 192.168.10.128 0.0.0.31RouterB(config)#access-list 10 permit anyRouterB(config)#interface Ethernet 0

RouterB(config-if)#ip access-group 10 out

19'1*'10'19+, +. /3 #its . th octet is the interesting octet 11100000 .$lock sie 2 . 3&et I45s 0 3 . 91* 10ost 19'1*'10'19 is in the 1* su#netso su#net 19'1*'10'1*

6ildcard is 0'0'0'31 one less than the #lock sie in the interesting octet'


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78tended Access Lists

100 - 199 or 000 99 78tended Access List place close to source

Stop telnet access to the net%orks attached to the 71 and 7 interfaces'

Rtr(config)#access-list 110 deny tcp any 172.16.48.0 0.0.1.2 e! 23Rtr(config)#access-list 110 deny tcp any 172.16.192.0 0.0.63.2 e! 23Rtr(config)#access-list 110 permit ip any anyRtr(config)#interface Ethernet 1Rtr(config-if)#ip access-group 110 out

Rtr(config-if)#interface Ethernet 2Rtr(config-if)#ip access-group 110 out

1,'1'20'1,3+0 lass $ address +1 3rd octet is the interesting octet +0 . #its #orro%ed11110000 .0$lock sie 2 - .0 10 1 3 .* .20 is in the .* su#net 1,'1'.*'0 %ildcard mask is 1 less than #lock sie 0'0'12'22

Note %e configure one access list containing #oth conditions and appl: it to the t%o interfacesrather than create one access list for each condition and place it on each interface'

Example


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Pre"ent S;


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Allow Access to a Range of Contiguous ! Addresses

Allo% all hosts in &et%ork $ %ith the net%ork address 19'1*'10'0+. to access net%ork19'1*'00'0+. in &et%ork A'

)access-list 101 permit ip 192.168.10.0 0.0.0.2 192.168.200.0 0.0.0.2 "source# "destination#

)interface ethernet0)ip access-group 101 in


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onfigure an e8tended access list name it secure@LA& to allo% pings from loop#ack 0 !outer $ toloop#ack 0 !outer A and also an access list to allo% an:one to telnet into loop#ack 1 on !outer Aonl:'

RouterA>enable

RouterA#config tRouterA(config)#ip access-list e*tended secure+,RouterA(config-ext-nacl)# permit icmp host 172.30.1.1 host 172.16.1.1

(source) (destination)RouterA(config-ext-nacl)# permit tcp any host 172.20.1.1 e! telnetRouterA(config-ext-nacl)#e*it source destinationRouterA(config)#int s0RouterA(config-if)#ip access-group secure+, inRouterA(config-if)#exitRouterA(config)#exit

onfirm %ith the sho% ip access-lists command

RouterA#sho( ip access-lists

Extended ip access list secure_LAN Perit icp !ost "$%&'%"%" !ost "$%"%"%" Perit tcp an !ost "$%$'%"%" e* telnet

Static &A<

4efine Inside Local and Inside lo#al Addresses

Router(config)#ip nat inside source static 10.0.0.3 179.2.2.80 Inside local outside glo#al

Router(config)#interface ethernet0 Router(config-if)#ip nat inside Router(config)#interface serial0 Router(config-if)#ip nat outside


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inside local outside glo#al(config)#ip nat inside source static 10.1.1.2 192.168.1.2(config)#int E0(config-if)#ip nat inside(config-if)#e*it(config)#int %0(config)#ip nat outside

4:namic &A<

A router needs to #e configured %ith &A< and it has 12 pu#lic addresses 1,9'9'*'*0 through1,9'9'*'92 call this pool@1' >n the inside net%ork hosts use the pri"ate addresses of 10'1'0'0+1'6hat is the &A< configuration on the routerB

(config)#access-list 1 permit 10.1.0.0 0.0.2.2(config)#ip nat pool $//,+1 179.9.8.80 179.9.8.9 netmas 2.2.2.0

pu#lic address pool(config)#ip nat inside source list 1 pool $//,+1(config)#int E0

(config-if)#ip nat inside(config)#e*it


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(config)int %0(config-if)#ip nat outside

Another 78ample

Router(config)#access-list 1 permit 10.0.0.0 0.0.0.2Router(config)#ip nat pool cisco 179.2.2.6 179.2.2.90 netmas2.2.2.224Router(config)#ip nat inside source list 1 pool cisco Router(config)#interface ethernet0 Router(config-if)#ip nat inside Router(config)#interface serial0 Router(config-if)#ip nat outside

lo#al outside addresses 2 therefore #lock sie 3 netmask 2 3 .

onfigure PA<

A #order router needs to #e configured %ith &A< and %ill allo% pu#lic addresses 19*'1*'131'2through ,0' >n the inside net%ork there are 3 hosts that use the pri"ate addresses of19'1*'10'19 through 190' 6hat is the &A< configuration on the #order routerB

Answer

#ip nat pool "odd 198.18.131.6 198.18.131.70 netmas 2.2.2.248

#access-list 1 permit 192.168.10.128 0.0.0.63#ip nat inside source list 1 pool "odd oerload


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ip nat pool +odd ",%"%"&"%. ",%"%"&"%' netas/ $..%$..%$..%$0

Sets the pool name as


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.' All pass%ords ha"e #een temporaril: set to DiscoD


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5ea1er>enale5ea1er#configure terminalRouter(config)#hostname (eaer5ea1er(config)#access-list 10 permit 192.168.100.16 0.0.0.15ea1er(config)#ip nat pool isp+adr 198.18.184.10 198.18.184.110 netmas2.2.2.248

5ea1er(config)#ip nat inside source list 10 pool isp+adr oerload

5ea1er(config)#access-list 10 permit 192.168.100.16 0.0.0.1

&um#er inside hosts 1. #lock sie 1 %ildcard 0'0'0'12Start of local pool 19'1*'100'1, lies in the 19'1*'100'1 su#net

19*'1*'1*.'102 110 2 addresses #lock sie * 2 * .* netmask 22'22'22'.*

5ea1er(config)#ip nat inside source list 10 pool isp+adr oerload

o"erload ke:%ord is compulsor: #ecause the internal LA& address space is more then the ISP

pro"ided pu#lic address range pu#lic address for 1. pri"ate lan hosts %hich all need to access theinternet at the same time'

--------------------1erif configuration--------------------

#clear ip nat translation 6#clear ip nat translation inside glob ip local ip 7outside glob ip localip8

#s!o9 ip nat translations#s!o9 ip nat statistics

Pass%ords

ena#le pass%ord (used to secure pri"ileged mode)ena#le secret the ne%er encr:pted pass%ord that o"errides the ena#le pass%ord

Router#config tRouter(config)#enale secret todd Router(config)#enale pass(ord todd

Au8iliar: Pass%ord

Router#config tRouter(config)#line au* 0Router(config-line)#loginRouter(config-line)# pass(ord todd

onsole Pass%ord

Router#config tRouter(config)#line console 0Router(config-line)#loginRouter(config-line)# pass(ord todd1

G


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Router(config)#line ty 0 4Router(config-line)#loginRouter(config-line)# pass(ord todd2

In effect the onl: line that changes is the line config


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$oots normall:'

Router#sho( interface s050Cerial'2' is up? line protocol is do9n

4atalink pro#lem' locking (keepali"e) or framing pro#lem' heck the keepali"es and encapsulationmatches on #oth ends and the clock rate is set if needed'

Router#sh int s050Cerial'2' is do9n? line protocol is do9n

Ph:sical la:er pro#lem' If #oth are do%n it5s a ca#le or interface pro#lem'

QuestionHou as the administrator issue the shutdo%n command on Serial 1' Hou later "ie% this interfaceusing the sho% interface Serial 1 command' o% %ill this interface #e displa:edB

A' Serial 1 is up line protocol is up'$' Serial 1 is up line protocol is do%n'' Serial 1 is do%n line protocol is do%n'4' Serial 1 is administrati"el: do%n the line protocol is do%n'

Answer 6

78planation


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Rconfig t Rconfig tR&(config)#int s' R&(config)#int s'R&(config-if)#no cdp enale R&(config-if)#cdp enaleR&(config-if)#:; R&(config-if)#:;


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6hat are the "alid hostsB 1- 2-1 19-190 193-2.

KuestionHou %ork as a net%ork technician' Hou ha"e su#netted the 01'102'13'0 net%ork %ith a + mask'Hour #oss asks :ou ho% man: usa#le su#net%orks and usa#le host addresses per su#net this %illpro"ide' 6hat should :ou tell herB

A' . net%orks and . hosts$' . net%orks and . hosts' net%orks and hosts4' net%orks and hosts

Ans%er

+ therefore #its #orro%ed for net%ork

Su#nets J - . - #its for net%ork portion therefore #its left for num#er of hosts J - .

Summariation

QuestionIn the net%ork sho%n #elo% %hat is the most efficient summariation that !1 can use to ad"ertiseits net%orks to !B

A' 1,'1'0'0+

$' 1,'1'0'0+1

' 1,'1'.'0+

4' 1,'1'.'0+2

1,'1'.'1*+2 1,'1'2'0+.


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1,'1''0+. 1,'1','0+.

7' 1,'1'.'0+1

Answer C

1,'1'.'0+

78planationE In large internet%orks hundreds or e"en thousands of net%ork addresses can e8ist' Itis often pro#lematic for routers to maintain this "olume of routes in their routing ta#les' !outesummariation (also called route aggregation or supernetting) can reduce the num#er of routes thata router must maintain #ecause it is a method of representing a series of net%ork num#ers in asingle summar: address'

1,'1'.'0 1,'1 E 00000100'01,'1'.'1* E 00000100'1*1,'1'2'0 E 00000101'01,'1''0 E 00000110'0

1,'1','0 E 00000111'0

1,'1 is the same for all net%orks 3 rd octet changes therefore reduce to #inar: to find the remainingcommon #its %hich is the first #its so +1 / + +

Quick Notes 8AN

96LC is the default encapsulation used 2y cisco routers o-er serial links No Authentication can 2e used with 96LC:

orporateRouter>enaleRouter#config tRouter(config)#hostname #orp3orp(config)#interface serial 03orp(config-if)#ip address 10.1.1.1 2.2.2.03orp(config-if)#no shutdo(n3orp(config-if)#e*it3orp(config)#e*it3orp#

ere the default 4L is used as orp router is cisco no configuration necessar:

A show interface serial ) sho%s 4L running'

outer)sho( int s0Cerial'2' is up? line protocol is upJ+K ".'' btes? B5 ".00 bitEncapsulation DL3? loopbac/ not set

PPP

If %e ha"e a isco router and a non-isco router connected %e must configure PPP 4L %on5t

%ork' Authentication can 2e used with !!!


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Left#config t Left(config)#username ight pass(ord cisco Left(config)#int s0 Left(config-if)#encapsulation ppp Left(config-if)# ppp authentication chap Left(config-if)# ppp authentication pap Left(config-if)#

Pass%ords must match on each router

?rame !ela:

4:namic address mapping using In"erse A!P ;ingle nterface

orporateRouter>enableRouter#config tRouter(config)#hostname #orp3orp(config)#interface serial 0

3orp(config-if)#encapsulation frame-relay3orp(config-if)#frame-relay lmi-type cisco3orp(config-if)#ip address 10.1.1.1 2.2.2.03orp(config-if)#frame-relay interface-dlci 1003orp(config-if)#no shutdo(n3orp(config-if)#exit3orp(config)#exit3orp#

&o encapsulation method %as specificall: configured the default is isco %hich means that aisco router is on #oth sides of the link'

If :ou ha"e a isco router on one side of the link and a &ortel or other on the other side of the link

then the configuration %ould #e'


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orporateRouter>enableRouter#config tRouter(config)#hostname #orp3orp(config)#interface serial 03orp(config-if)#encapsulation frame-relay ietf

3orp(config-if)#frame-relay lmi-type ansi or .933 )3orp(config-if)#ip address 10.1.1.1 2.2.2.03orp(config-if)#frame-relay interface-dlci 1003orp(config-if)#no shutdo(n3orp(config-if)#exit3orp(config)#exit


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show frame p-c 4ispla:s the ?7& $7& and 47 "alues'

R1#show frame pvc

PVC Statistics for interface Serial0 (Frame Relay DTE)

Active Inactive Deleted Static

Local 2 0 0 0

Switched 0 0 0 0

Unused 0 0 0 0

DLCI = 122, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial0

input pkts 30 output pkts 0 in bytes 2280

out bytes 0 dropped pkts 0 in FECN pkts 0

in BECN pkts 0 out FECN pkts 0 out BECN pkts 0

in DE pkts 0 out DE pkts 0

out bcast pkts 0 out bcast bytes 0

pvc create time 00:07:45, last time pvc status changed 00:06:55

;u2interfaces


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Point-to-Point

entralRouter>enableRouter#config t

Router(config)#!ostnae 3entral

3entral(config)#interface serial 03entral(config-if)#encapsulation frame-relay3entral(config-if)#frame-relay lmi-type cisco3entral(config-if)#no shutdo(n3entral(config-if)#no ip address

3entral(config-if)#interface serial 050.1 point-to-point3entral(config-subif)#ip address 10.20.1.1 2.2.2.03entral(config-subif)#frame-relay interface-dlci 1

3entral(config-if)#interface serial 050.2 point-to-point

3entral(config-subif)#ip address 10.20.2.1 2.2.2.03entral(config-subif)#frame-relay interface-dlci 2

3entral(config-if)#interface serial 050.3 point-to-point3entral(config-subif)#ip address 10.20.3.1 2.2.2.03entral(config-subif)#frame-relay interface-dlci 33entral(config-if)#exit3entral(config)#exit


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;ultipoint and point-to-point su#interfaces can coe8ist

RouterA(config)#interface serial 050RouterA(config-if)#no ip address (optional)(reo1es ip address onl re*uired if t!e interface alread had an ip address)RouterA(config-if)#encapsulation frame-relay ietfRouterA(config-if)#frame-relay lmi-type ansiRouterA(config-if)#interface s050.2 point-to-pointRouterA(config-subif)#ip address 2.1.1.1 2.2.2.0RouterA(config-subif)#frame-relay interface-dlci 20 roadcast

RouterA(config)#interface serial 050RouterA(config-if)#encapsulation frame-relayRouterA(config-if)#frame-relay lmi-type ciscoRouterA(config-if)#int s050.1 multipointRouterA(config-subif)#ip address 1.1.1.1 2.2.0.0RouterA(config-subif)#frame-relay map ip 1.1.1.2 18 roadcast

RouterA(config-subif)#frame-relay map ip 1.1.1.3 19 roadcast

RouterA(config-subif)#frame-relay interface-dlci 18 roadcast


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.. displa:s statistics for all interfaces configured on the s%itch sho%s L;Itraffic encapsulation as %ell as La:er- and La:er3 information'

sho( frame map sho%s net%ork la:er-to-4LI mappings


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IS4&

IS4& $!I is made up of t%o $ channels of .k each and one 4 channel of 1kalso referred to as $ / 4


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dot$@ Example

It is recommended that the su#-interface "alue is the same as the GLA&'

switchportHou onl: use the s%itchport command on s%itchesMnot routers'

Hou can configure an interface to #e an access linkC9itc!(config-if)#s(itchport mode access

>r put a port in a certain GLA&C9itc!(config-if)#s(itchport access lan 101


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reating GLA&5s

%1)config t

C"(config)#lan 2C"(config-1lan)#name %alesC"(config-1lan)#lan 3C"(config-1lan)#name &aretingC"(config-1lan)#lan 4C"(config-1lan)#name accountingC"(config-1lan)#

After :ou ha"e created GLA&s "erif: them %ith a sho( lan command

show -lan

%1)sho( lan


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C"(config-if)#s(itchport mode accessC"(config-if)#s(itchport access lan 3

%1)config tEnter configuration coands one per line% End 9it! 3N+RL2;

C"(config)#lan C"(config-1lan)#name maretingC"(config-1lan)#e*itC"(config)#lan 10C"(config-1lan)#name humanresourcesC"(config-1lan)#e*it

C"(config)#interface astEthernet 052C"(config-if)#s(itchport mode accessC"(config-if)#s(itchport access lan C"(config-if)#e*itC"(config)#interface fastEternet 053C"(config-if)#s(itchport mode access

C"(config-if)#s(itchport access lan C"(config-if)#e*itC"(config)#interface fastEternet 054C"(config-if)#s(itchport mode accessC"(config-if)#s(itchport access lan 10C"(config-if)#e*itC"(config)#interface fastEternet 05C"(config-if)#s(itchport mode accessC"(config-if)#s(itchport access lan 10C"(config-if)#e*itC"(config)#

At this point ports and 3 can communicate %ith each other and ports . N 2 can communicate'


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Question6hat command %ill configure an interface on a atal:st 900 series s%itch to carr: traffic from allGLA&s to another directl: connected s%itchB (hoose t%o)

A' S%itch(config-if) "lan all$' S%itch(config-if) s%itchport access "lan 30

' S%itch(config-if) s%itchport access "lan all4' S%itch(config-if) s%itchport mode trunk7' S%itch(config-if) s%itchport trunk encapsulation dot1C

Answer C, E

S%itch(config-if) s%itchport access "lan allS%itch(config-if) s%itchport trunk encapsulation dot1C

S%itches ha"e 3 G

onfiguring the 4omain

",''(config)#tp mode serer",''(config)#tp domain #isco2",''(config)#tp pass(ord cantona

G


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Question

ost A in the graphic is connected to a s%itch port assigned to GLA& 1' 6hich t%o settings on host A are reCuired to allo% connecti"it: %ith ost $ on GLA& B (hoose t%o)

A' IP addressE 19'1'1' 22'22'22'.0$' IP addressE 19'1'1'130 22'22'22'19' IP addressE 19'1'1'1. 22'22'22'.04' 4efault gate%a:E 19'1'1'197' 4efault gate%a:E 19'1'1'2

?' 4efault gate%a:E 19'1'1'1

Answer C, 6

78planationSu#-interface ?ast 7thernet 0+0' %as created for GLA& 1"ia the Dencapsulation dot1C 1D command'

is correct asost A resides in GLA& 1 it must #e configured %ith an IP address in the 19'1'1'1*+*su#netGLA& 1 19'1'1'19 22'22'22'.0 host rangeB2 .0 1 $lock Sie01 3 .* . *0 9 11 1* 1..

19 is in the 1* su#net "alid hosts 19 - 1.


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4 is correct asost A must #e configured %ith the IP address of the default gate%a: %hich is the IP addressassigned to the su#-interface of the router'

Question6hich of the follo%ing are "alid configuration "alues for the hosts sho%n in the graphicB (choosethree)

A' host A IP addressE 19'1'1'2

$' host A su#net maskE 22'22'22'.

' host $ IP addressE 19'1'1'12

4' host $ default gate%a:E 19'1'1'2

7' host IP addressE 19'1'1'1

?' host su#net maskE 22'22'22'.

Answer C, 6, 0

78planationGLA&1 19'1'1'2 22'22'22'19 hostsB2 19 . $lock Sie0 . 1* 192 lies in the . su#netost range 2 -1

GLA&10 19'1'1'19 22'22'22'.2 . 3


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0 3 . 9 1* 1019 lies in the 1* su#netost range 19 -2*

!outing

!oute A4onnected 0Static 17I!P 90I!P 100>SP? 110!IP 107nhanced7I!P 1,0nkno%n 22

Link-state routing uses

Linkstate ad-ertisements "L;As# B A link-state ad"ertisement (LSA) is a small packet of routing information that is sent #et%een routers'


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4' n the LA& side of each of theselocations :ou ha"e a small 7thernet net%ork'


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78ample!outer$ is connected to the net%orks 19'1*'0'0 19'1*'30'0 and 19'1*'.0'06e must configure the follo%ing static routes on !outer$19'1*'10'0

19'1*'20'0

RouterB(config)#ip route 192.168.10.0 2.2.2.0 192.168.20.1RouterB(config)#ip route 192.168.0.0 2.2.2.0 192.168.40.2

&o% looking at the routing ta#le :ou can see !outer$ understands ho% to find each net%ork'outer:)sho( ip route3odesF 3 - connected? etcM

C ",$%"%.'%' 7"2'8 1ia ",$%"%0'%$3 ",$%"%0'%' is directl connected? Cerial '2"3 ",$%"%&'%' is directl connected? 4astEt!ernet'2'3 ",$%"%$'%' is directl connected? Cerial '2'

C ",$%"%"'%' 7"2'8 1ia ",$%"%$'%"RouterB#

4efault !oute

A default route ser"es as a gate%a: of last resort' If there are no matches for a destination in therouting ta#le the default route %ill #e used'

R"(config)#ip route 0.0.0.0 0.0.0.0 200.1.1.2 ne*t-hop '$ address;R"(config)#ip route 0.0.0.0 0.0.0.0 serial0 local e*it interface;


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D% ip route $..%$..%$..%$.. $..%$..%$..%$.. "$%"%"%"E% ip route $..%$..%$..%$.. $..%$..%$..%$.. serial"4% ip route $..%$..%$..%$.. $..%$..%$..%$.. ",%"$%"$%"$I% ip route $..%$..%$..%$.. $..%$..%$..%$.. serial'% ip route '%'%'%' '%'%'%' "$%"%"%"

Answer A, C

78planation


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onfigure !outer A use the net%ork I4 of 19'1*'1.'0+*'


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If the passi"e interface command is ena#led on the fa0+0 interface of !outer 7 %hich statementsare trueB (hoose t%o') A' !outer 7 %ill send all routing updates "ia interface fa0+0'$' !outer 7 %ill ignore all routing updates learned "ia interface fa0+0'' !outer 7 %ill use routing updates learned "ia interface fa0+0'4' !outer 7 %ill not send routing updates "ia interface fa0+0'

Answer C, 6

!outer 7 %ill use routing updates learned "ia interface fa0+0'!outer 7 %ill not send routing updates "ia interface fa0+0'

!IP" is a classless routing protocol (e"en though it is configured as classful like !IP"1 it sendssu#net mask information along %ith the route updates)

Router3(config)#router ripRouter3(config-router)#ersion 2Router3(config-router)#net(or 192.168.40.0Router3(config-router)#net(or 192.168.0.0

!IP "ersion default #eha"ior is to autosummarie routes ad"ertised across classful #oundaries'


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It #roadcasts it entire routing ta#le e"er: 30 seconds #: default and it can #e load #alanced asman: as si8 eCual cost paths (. paths are the default)'

QuestionHou are configuring the Ike router on the net%ork sho%n in the figure #elo%' Hou %ould like to usethe !IP routing protocol to propagate all the net%orks to the three routers sho%n' 6hat

configuration %ould :ou appl: to Ike to ha"e it participate in this o#Recti"eB

A% H/e(config)#router rip H/e(config-router)#net9or/ "$%"%'%' H/e(config-router)#net9or/ ",$%"%0.%'

B% H/e(config)#router rip H/e(config-router)#net9or/ "$%"%&'%' H/e(config-router)#net9or/ ",$%"%&.%' H/e(config-router)#net9or/ ",$%"%0.%' H/e(config-router)#net9or/ ",$%"%..%'

3% H/e(config)#router rip H/e(config-router)#net9or/ "$%"%'%' H/e(config-router)#net9or/ ",$%"%&.%' H/e(config-router)#net9or/ ",$%"%0.%' H/e(config-router)#net9or/ ",$%"%..%'

D% H/e(config)#router rip H/e(config-router)#net9or/ "$%"%'%' H/e(config-router)#net9or/ ",$%"%'%'

Answer A

!IP is considered a classful protocol' ?rom a configuration standpoint this means that net%orksmust #e entered into the configuration using their default classes (lass A $ or )' $ecause1,'1'0'0 is a class $ net%ork it must #e entered as if it had a class $ su#net mask rather thanthe su#net mask sho%n in the figure' In addition :ou enter directl: connected interfaces onl: into arouting process

7I!P

7I!P is a classless enhanced distance "ector Cisco proprietary protocol'It includes the su#net mask in its route updates

It doesn5t send link state updates like >SP? #ut sends distance "ector updates %ith info a#out

net%orks and the cost of reaching them' $ut like link state it s:nchronises routing ta#les #et%eenneigh#ors at startup and %hen the topolog: changes


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7I!P hello messages are sent e"er: 2 secs on 7thernet #: default'7I!P has a ma8imum hop count of 100 #ut it can #e set up to 22'

Router#config tRouter(config)#router eigrp 20

Router(config-router)#net(or 172.16.0.0 Router(config-router)#net(or 10.0.0.0

&ote the AS num#er 0 %hich can #e an: num#er 1 to 2232

Router(config)#router eigrp 20Router(config-router)# passie-interface serial 051

ER! passi-e interfaces differ to R! they will neither send nor recei-e updates.

7I!P also supports the use of discontiguous su#nets

6iscontiguous su2nets work with D;!0 2y default 2ecause D;!0 does not autosummariselike ER!.

A 6iscontiguous Network

ere the su#nets 1,'1'10'0 and 1,'1'0'0 are connected together %ith a 10'3'1'0 net%ork' $:default each router thinks it has the onl: 1,'1'0'0 classful net%ork'

Configuring 6iscontiguous Networks

$: default routers running 7I!P %ill automaticall: summarise the classful #oundaries and routing%ill not %ork' ere5s ho% to turn auto summarisation off'

outer)config tRouterA(config)#router eigrp 100


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RouterA(config-router)#net(or 172.16.0.0RouterA(config-router)#net(or 10.0.0.0RouterA(config-router)#no auto-summary

outer:)config t

RouterB(config)#router eigrp 100RouterB(config-router)#net(or 172.16.0.0RouterB(config-router)#net(or 10.0.0.0RouterB(config-router)#no auto-summary

$: using the no auto-summary command 7I!P %ill ad"ertise all the su#nets #et%een the t%orouters'

In the presence of discontiguous su#nets automatic summarisation must #e disa#led for routing to%ork'

7I!P topolog: ta#le

Routes with larger metrics to the network -ia other routers, is the Reported 6istance "R6#.

A ?easi#le Successor is a neigh#or %hose !eported 4istance is less than the current ?easi#le4istance'

SP? cant load #alance across uneCual cost links as 7I!P can'


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>SP? supports GLS; has no limitation of net%ork reacha#ilit: it maintains neigh#or relationshipsusing the IP multicast address of .'0'0'2' After initialiation >SP? onl: sends updates on routingta#le sections %hich ha"e changed it does not send the entire routing ta#le'

Router 6 nl: the 4! %ill send LSAs to the rest of the net%ork'

• ?or #ackup purposes also a $ackup 4! ($4!) is elected

• All routers also esta#lish adRacencies to the $4!

• $4! itself also esta#lishes adRacenc: to 4!

R"#sho( ip ospf neighorNeig!bor HD Pri Ctate Dead +ie Address Hnterface$%$%$%$ " 4KLL2BDR ''F''F&0 ",$%"%"$%$ Cerial"2"&%&%&%& " 4KLL2BDR ''F''F& ",$%"%"&%& 4astEt!ernet'2'

Neigh2orship data2ase A "ariet: of details such as the !outer I4 and state are maintained oneach router in the neigh#ourship data#ase it is a list of all >SP? routers %hich ha"e recei"ed hellopackets'

onfiguring Priorit:


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A router with the highest D;!0 priority will win the election for 6R.

Rconfig tR&(config)#interface f050R&(config-if)#ip ospf priority 100

&ote %e ha"e to reload or shutdo%n the routers for election to take place and priorit: take effect'

6e can see Priorit: %ith sho( ip ospf interface

3)sho( ip ospf interface4astEt!ernet'2' is up? line protocol is upHnternet Address ""%".0%0.%&, Area 'Process HD 0,,, Router HD ""%".0%0.%&, Net9or/ +pe BRAD3AC+ 3ost "'+ransit Dela is " sec %tate


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onfiguring >SP? Areas

After the >SP? process %e need to identif: the interfaces and area on %hich :ou %ant to acti"ate>SP?'

RouterA#config tRouterA(config)#router ospf 1RouterA(config-router)#net(or 10.0.0.0 0.2.2.2 area 0In multi-area >SP? net%orks all areas are reCuired to connect to area 0 the #ack#one area'

SP?)


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La:er S%itching

0orward*filter decisions 6hen a frame is recei"ed on an interface the s%itch looks at thedestination hard%are address and finds the e8it interface in the ;A data#ase'


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Spanning


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An: port that is not either a root port or a designated port is placed into the #locking state'

S%itch A is the root #ridge #ecause it5s the one %ith the lo%est #ridge I4' S%itch $ must shut do%none of its ports connected to S%itch A to pre"ent a s%itching loop from occurring'

S


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In order to allo% mo"ement #et%een the cells %ithout the loss of signal $SSs must o"erlap #:appro8imatel: 10'


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6i-?i Protected Access (6PA)' Specifies the use of d:namic encr:ption ke:s that change each timea client esta#lishes a connection' It includes authentication #: PST'

QuestionHou and a co-%orker ha"e esta#lished %ireless communication directl: #et%een :our %irelesslaptops' 6hat t:pe of %ireless topolog: has #een createdB

A' $SS$' 7SS' I$SS4' SSI4

Answer C

Explanation Ad-hoc mode or Independent $asic Ser"ice Set UI$SSV is simpl: a group of computers talking%irelessl: to each other %ith no access point (AP)'

IP"

14AE0043E0000E?3$E0AAE00??E?7*E92A or

14AE43E0E?3$EAAE??E?7*E92A %ith the leading eros remo"ed

A contiguous seCuence of 1-#it #locks set to 0 in the colon-he8adecimal format can #ecompressed to EE

?7*0E0E0E0EAAE??E?79AE.A can #e compressed to ?7*0EEAAE??E?79AE.A'

??0E0E0E0E0E0E0E can #e compressed to ??0EE'

0000 ma: #e replaced %ith t%o colonsEE as long as there is onl: one dou#le colon used in anaddress

"$&0F'F'F'FAB3DF'F'F"$&

could #e represented as"$&0FFAB3DF'F'F"$&

or"$&0F'F'F'FAB3DFF"$&

Hou can identif: these and other IP" addresses #: their initial #its

1111 111010 - Link Local prefi8 0E()GG*$)

1111 111011 a site-local address IP" unicast address prefi8 0EC)GG*$)

1111 1111 ;ulticast has a prefi8 of 00))GG*(

to. is &))&GG*$' - this is the transition s:stemMthe structure that allo%s IP" packets to #etransmitted o"er an IP". net%ork %ithout the need to configure e8plicit tunnels'

Autoconfiguration


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;A-.*E 00E01E03E9E*$E? 7I-.E 001E03ffEfe9E*#cf

Example

ost 7thernet address is 00E30E.*E3E2*Edf

&et%ork prefi8 is 001Ed#*E1EcafeEE+.

Address is

001E0d#*E0001EcafeE030E.*ffEfe3E2*df


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A router that is running #oth IP". and IP" addressing on the same interface is kno%n as4ual-stack

33597689 Ccna Quick Revision Notes

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