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Free CCNA | EIGRP Introduction – Day 49 | 200-125 | Cisco Training


Cisco Certified Network Associate Day 49
welcome back everyone I’m Imran Rafai, your trainer for this entire
series today we are doing EIGRP introduction which is…. with OSPF…
EIGRP is….. these two topics are one of our most sought-after topics…
ever …right through from the time we started the series people have requested for EIGRP and OSPF and OSPF we did in the last few videos today we start
EIGRP so without wasting much time let’s get straight to this class before
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for us today today we would go go so we finished 2.4
so we will go from 2.4 to 2.6 we have not done 2.5 welcome back to 2.5 later
but we would be doing 2.6 today so that’s configure verify troubleshoot a
EIGRP for IP version 4 excluding authentication filtering manual
summarization redistribution stuff so this is configure verifying troubleshoot
topics but in today’s video we would only be doing introduction so we will
need to youth concepts of AI GRP and then in the
next video and the video after that we will look at
troubleshooting and configuration right so before we go ahead I want you to take
a moment right we did about four videos of four or five videos of year OSPF so I
want you to think when we when we did rip many many many moons ago we learned
that there was loop right there was a way they were
it was creating loops there were possibility of loop creations and we
looked at few loop prevention techniques what are those techniques in OSPF how do
you prevent loop in OSPF do we use a route poison and what about splitter
eysan do we you split horizon in OSPF so this is for you to find out use google
or read other resources but find answer for this question because i want if you
tried doing some research for yourself you’re going to remember that so I want
you to remember I want it to research I want you to understand and once you find
an answer comment in the comment section below and let’s see how many of you’ll
find answer and how many feel comment so what is e IG RP e IG RP is a hybrid
routing protocol now why do we call hybrid because it takes some good
features from distance vector routing protocol like rip and it takes some good
features from link state routing protocol like OSPF right so it’s a
hybrid technology it takes the good part from both these routing protocols and
then it has it cisco developed its own routing protocol called a IG RP so what
does it take from link state it takes the formation of neighbors so it forms
neighbors like unlike rip rip doesn’t form neighbors it just chatters I just
tells its neighbor whoever the neighbor is just chatters saying this is my
routing table this is the router I know right that’s what is rip did but OSPF
before it exchanged update it formed neighbors EW GRP
forms neighbors just like OSPF also if you remember rip-rip did periodic update
every 30 seconds there was a update and update was full routing table it sent
everything new to its neighbor of course with split horizon a rule it did not
send back route information about the rods that it learned from a certain
interface but other than that it sends all the interface all the routes that
Hypno’s from its routing table to its neighbor so eh RP didn’t want to do that
so EIG up it does not do full periodic update but if you remember OSPF did
hello so AIG RP also takes that Helu concept so every few seconds it sends
hello message to make sure the neighbor is still alive so rip did not do that
but oh oh oh SPF did that and ERG up uses it too what does it take from
distance vector unlike OSPF which is a link state
routing protocol which learns about the entire network topology before it makes
his routing decision yeah our Peters don’t do that
yeah ARP is more like rip it just routes by gossip
now when I say routes by gossip your neighbor tells you something and yeah
ARP just like rip would accept it if if the neighbor says that he knows how to
go to ten dot wonder 1.2 that’s it he just listens and he does not ask how do
you know tell me the entire know the topology network topology doesn’t ask
all that it just believes whatever the neighbor says just like rip so it works
like rip with routing with gossip yeah ARP was a cisco proprietary
trotting protocol until 2013 so before 2013 you had to have a cisco
infrastructure if you wanted to use GI GRT so what happened is before 2013 even
people and companies with cisco infrastructures they were reluctant to
use the edge erp in spite of EIGRP being a better protocol at least my personal
opinion Europe is a much much better and much
more easier protocol right in spite of being easier and much
better people were reluctant to use the idea pen they chose you os PF and that’s
why OSPF is the most used routing protocol that was because they don’t
want to lock themselves with cisco safe if you if you start a company and if you
configure CR GRP knowing that EIGRP needs cisco infrastructure so in future
if you wanted to invest in let’s say juniper or some other network
infrastructures right if you want to expand with other companies products you
couldn’t do it the cause of your GRP so in 2013 Cisco said we would make EA GRP
an open standard that means anybody could use VI GRP if they want so now if
you’re using non Cisco devices ERP is supported so that’s something that
happened in 2013 and that is a brilliant brilliant move by Cisco so if you look
at little little bit of history lessons rip version one was introduced in 1980s
early 80s rip was introduced rip had the limitations repair a lot of limitations
especially 16 hop which is the maximum it could do anything more than 16 hope
it wouldn’t support so if the network is a little big rip really failed there so
cisco introduced something called as IG RP internal gateway routing protocol and
then it was much much better than the RIP protocol but still it had more
distance vector was more related to distance vector than link state end of
the 80s OSPF will open standard OSPF for IP version 4 which is always P version 2
was released with link state so that was totally different was a new concept
early 90s cisco said ok this is time we need to upgrade we need to enhance igr p
so cisco created IG RP which is enhance IGRT
enhanced interior gateway routing protocol yes sharpy suddenly became much
better than OSP of because it took few qualities from OSPF it took few
qualities from grip and then it sir I became the best routing protocol that
is then and if you see here are th IP routing you know if you in our next
video when we look at configurations you will see eigrp configuration is much
much easier than OSPF so this is co wanted it to be easy it wanted to be
converging much much faster faster than OSPF as well and they wanted it to be
the best and it is quite honestly the best routing protocol among the three
later rip wanted to support classless so rip did lot more upgrade and the
repulsion to was introduced in the 90s in the 2000s rip where OSP version 3 to
support ice IP version 6 rip ng also supported IP version 6 and EIGRP v6
these were all three introduced to support IP version 6 because the world
was slowly moving towards IP version 6 and all these routing protocols wanted
to be ready so if you remember what we learnt in rip we realized if let’s say
from router one you want to go to router 3 if you do some network the routing
table would always use it would be populated by this route because imagine
of what what speeds this works at so if this was working at 64 kbps and these
were all 1 5 4 4 kbps right even this one 5 4 4 kb PS rip would always choose
this because rip did the only criteria or metric for it is hop count and this
has one hop count this would be 2 hop count but OSPF would look at this whole
topology and would choose to go through this EHR P also even though it does a
lot like this is vector it would look at the metric now in in rip the metric was
hop count in in OSPF the metric was cost and cost was inversely proportional to
the bandwidth but in erp it’s caused a game
alright the method metric is cause but then it is much more complicated it
takes into consideration bandwidth and delay by default these two are taken
into consideration but you could also tune energy RP to take into
concentration Lord so if a particular interface is being loaded you could make
sure that you get negative points and you would prefer something that is less
loaded right so that’s also something that you could do but for your CCNA
level we will be considering the metric formula which considers only bandwidth
and delay which is the default formula let’s try to brush up our knowledge on
distance vector especially rip we will see what we learned so if you remember a
rip rip when it did it had distance vector when it’s a distance vector like
we saw in the previous slide if there were three routers right the routing
table had two information if let’s say it has to go to network 20 whatever
20.000 so rhotic table here had the distance
write distance is hop so this is one hop so distance was one and it had a vector
vector is direction it had tell which way to go whether it has good this way
or that way so that’s why the name distance vector
comes it has a distance which is in this case hop and a vector which is the next
route where did is where does it have to go that’s vector that’s how the name
distance vector comes so that’s how rip did it then it did a periodic full
update so if you remember drip every 30 second sent out an update an update like
we discussed earlier it sends the full routing table now the periodic 30
seconds update of RIP had to function one was to update its routing table
whatever is in a sorting table is updated to the neighbor and also to
eight served the action of check if their neighbors alive
so if it doesn’t get a routing update from a neighbor
30 seconds if it sends and what if I mean it’s it sends it sees that it
doesn’t get an update from a neighbor or update about a route it knows that rod
could be out so you have the dead time whole time and all the timer that we
discuss so every 30 second it sends and it resets those timers and that’s how it
checks for life checks at those routes or those networks are still valid so the
periodic update releasing an update did to function one update and then it also
checked life like we discussed because of the problem of loop we use split
horizon so when he says split horizon what it said it said it would not send
back routes or updates on the same interface through which it learnt those
interfere those routes in the first place so split horizon rule was used to
prevent loop and route poisoning was another method where there was a
triggered update so whenever a particular network went down especially
if this let’s say in this case this network goes down this router sends a
poisoned route poisoned route means it creates the hop 216 which is a poisoned
route and it triggers an update it doesn’t wait for the 30 second time to
finish it triggers an update sends it to neighbors saying that this network is
now at sixteen hops right so these are the things what rip did to prevent loop
and how it worked now how does a IGRT work now if you remember from OSPF video
few videos ago we did OSPF introduction and that we learnt that OSPF did three
things first thing it formed neighbors second so that’s what it HEA also is
gonna do it forms neighbor that’s first step second step is to apology exchange
right so if you remember in that they said LSD be update now LSD be exchanges
it exchange LSD be Allah says it exchange ELISA to update
its ALS TV and then third step was to form a routing table now forming
neighbor with OSPF was very very complicated it had a lot of parameters
and then once it checks all those parameters it would stay in twos two-way
state some of those would go from too way too full
some of them would still stay into it in OSPF and EIGRP there’s nothing like that
all it checks it checks for parameters so like OSPF EIGRP wants one to enable
ER GRP every 10 seconds it sends out IL hello right it sends hello in the hello
there are four parameters there is an authentication so if there is any
authentication that you set up there is authentication values so both the
devices need to have the same authentication parameters it should both
be part of the same autonomous system so let’s have a new configure yep you’ll
see eigrp n is given autonomous system so both the devices should have the same
autonomous system numbers then it both needs to have the hello message should
be coming from the same source IP right if there are two devices that there
should be a common interface through which I’m saying a common sunlit through
which the hello packet is coming and then the key values should match now k
values is if you remember and maybe I’ll show you later why a little while later
in the formula there are K values so it’s 0 or 1 if it is 0 those whatever
the parameter is obviously it’s not it’s ignored and whatever K value that you
give as 1 those parameters are used in the formula so the K value should match
and for CCNA don’t tamper with your K values let that K values be the default
ones and that’s what cisco recommends in fact don’t tamper with your K values so
if these four parameters match for EA GRP you are a neighbor so those two
devices will become neighbor and they would add each other’s to their neighbor
tables the next is the topology exchange so
it’s cents updates – it depends I mean depends the hello hello message would go
to this multicast IP address so this is multicast hello will always go to this
multicast and to whoever is doing here JP let me just clear the screen so hello
hello message we’ll go to this multicast 22 24.000 to either it could go to the
unicast IP address of the neighbor or it could go to a multicast depending on how
its configured and these updates are communicated not by UDP or TCP it uses
another protocol called reliable transmission protocol RTP it’s used by
EIGRP it’s a reliable transport protocol that so it can check if the neighbor
received update so if you send an update and RTP you can check if the neighbor
has received it if it’s not it can pre transmit the updates so it’s it can make
sure that the neighbor has seen the updates unlike OSPF you don’t have a
mechanism for the receiving device you tell that it hasn’t received it eh okey
now if you remember we said rip sends the full topology full update every 30
seconds but ERP sends full update the first time so whenever a device comes on
it sends the full update it sends full information about all the network’s
routes that it knows or when there is a change if there’s a change it just sends
the updates it doesn’t send the entire table again whatever that network which
is change only that network update so it’s more like a partial update it it
sends partial updates when it required it doesn’t send full update again so for
instance let’s say if you configure ERP and for one year nothing changes on the
only on your new network all the networks are working then ERP will not
send update for one year unlike an OS bf if you remember OSPF type one Alice’s
a timer of 30 minutes so no matter what happens even if there’s no change every
30 minutes the La Silla the type 1 LS say whichever outer generator those
Alice’s will see that the timer which is 30 minutes has passed and it will
recreate and resend those LS a so OSPF every 30 minutes Alice’s will be updated
and it has to do that recalculation whatever that does but in in eigrp if
nothing changes you will not have anything no updates ERP updates
happening for whatever time that change does not happen so that’s that’s why we
a job is much more efficient and the third step of course is to build the
routing table so for neighbor topology exchange and then build routing table no
build routing table we use this metric this is the formula that is used to
calculate costs and depending on the cost we create the or populate the
routing table now what happens so initially let’s say our one sends a
hello to our to our two sins hello to our one as soon as this is done
if everything matches then they will have a neighbor table neighbor table so
in the neighbor table our two will list our one as a neighbor and our one will
list neighbor as our two so our to is listed in our ones neighbor table and
our one is listed in our to thing per table once this is done it updates it
sense our to algebra the our one would send the ten dot network to our one so
if you see the routing table it would say 10.1.1.10 top is f 0 / 0 and
whatever the cost would be shown here admin distance for eh ERP is 90 so if
you remember OSPF was 110 ERG RP is 90 and then we would have a feasible
distance value and we will talk about that in a while but your routing table
will have this information so we talked about metric so this is a metric now if
you see actual metric is slightly more complicated this you will have K value
so you’ll have bandwidth then divided by you would have K values then you will
have some K values here this is k3 whatever may be I think I don’t know if
I have it let me just quickly shoot you so this is from cisco’s website so if
you see this is a formula k1 and k2 bandwidth bandwidth whatever this this
is a formula and these are default values K 1 and K 3 is 1 K 2 K 3 K 4 K 5
are zeros so if you do a substitution of these values you finally the value the
the formula is reduced to bandwidth plus delay into 256 right so that’s what we
have used so if you look at our me just clear this so we reduce whatever that
using the default K values this is what we get so we get bandwidth the bandwidth
is nothing but 10 to the power 7 divided by whatever bandwidth that you have so
we will look at in the in the next slide we will see what I mean by the least
bandwidth but the formula is always 10 to the power 7 divided by least
bandwidth plus cumulative delay no accumulated delay is the delay from from
top whichever route of you are talking about till the till the subnet that we
are talking about where we are trying to find the root so the delays you need to
add all the delays in between right and Lee’s bandwidth is the lowest bandwidth
between all these things we will see how that is derived but this is the formula
just remember this formula talking of eigrp these are the four topics that you
need to learn that’s feasible distance reported distance successor and feasible
successor so let’s take a topology and we’ll try to understand these four terms
and once you understand these four terms other we are ready to start configuring
erp so let’s as you we are trying to populate our one
sorting table are ones routing table is what we’re interested in and we are
trying to go to this network 10.1.1.10 T for right now this is the bandwidth and
delay no bandwidth and delay you could have by default so by default gigabit is
one gigabit per second gbps your to convert that into kbps that becomes 1
million kbps right 10 to the power 6 or you talk about 100 Mbps that’s 100,000
QPS if you’re talking about Ethernet that’s 10,000 QPS or 10 Mbps you talk
about you know serial connections 1 5 4 4 kbps so accordingly the delay also is
calculated by Cisco so if you look at if you go to show interface G 0/0 it would
tell the whatever that bandwidth is and whatever delay is right these are the
physical property so for instance if you look at serial serial bandwidth by
default is 1 5 4 4 even if this is a 64 kbps line it would still say 1 5 4 4
cube appear so you as administrator should be very careful and you should
make sure that you put the correct values for the bandwidth and of course
delay would be you could again change the delay with the command so if you go
into that interface and say bandwidth and you can give bandwidth and delay and
you can give delay so whatever that you want you could give from that interface
but whatever that is configured you need to make sure that especially in serial
if if you leave Gigabit Ethernet and facet them if you leave but the default
values you should not have much problem but your serial interfaces be careful
that you have to set whatever the land speed is another thing that you need to
look at and these all saying milliseconds ms is milliseconds but
actually they are microseconds micro is a sign like that mu if you know
Mew is so microsecond but there is I didn’t have the same use mus that’s why
I said ms/ms so if you look at Cisco it says us us is nothing but you there no
writing you four microseconds it’s actually 200 microseconds 10
microseconds another thing what you need to be careful is if you look at the show
interface show interface G 0 star 0 it lists the delay by microsecond but if
you’re configuring if you go into the interface and then you want to configure
a spread certain delay you say delay day if you if you look at the unit there it
says tens of micro second so 10 micro second will become one tens of
microseconds so we will look at that tomorrow in the next video that is when
we do configuration but this is something you need to be careful the
configuration when you configure manually it is not micro it is tens of
microseconds so it’s less so let’s do this and also and it’s not only for
configuration even in our form if even in our calculation it uses tens of micro
so if you’d say 10 micros 100 micro second in the formula for delay it is
actually taking 10 because it’s doing tens of microseconds if just you need to
remember that right so when you do the calculation so now this is the bandwidth
for this interface and this is the delay this is the bandwidth for this interface
and this is the bandwidth for this interface bandwidth and delay rather
bandwidth and delay bandwidth and delay for this interface bandwidth and delay
for this interface bandwidth to deliver this interface and this interface so we
need to first find feasible distance feasible distance is the metric right
it’s it’s a metric once you put the formula you put all that calculation
whatever that you get is the feasible distance so for this
if you use the family that would be 10 to the power 7 divided by this is what
10 to power 6 10 to the power 6 so if you do 10 to the power 7 divided by 10
to power 6 that is 10 right if you know what it is 10 to the power 10 to the
power 7 divided into power 6 is 10 plus delay is 1 microsecond if you do tens of
if you do tens of microseconds that is 1 so that is in two so if you remember
formula this into 2 5 6 that is 11 into 2 5 6 which is nothing bad 2,860 that’s
the value of your feasible distance and this is the value so if you look at the
cost if you look at the cost for this router or the 5 to go to 10 dot this
network that’s directly connected but the feasible distance is 2 8 1 6 now
this 2 8 1 6 when a IGRT sends routing updates it would send this information
saying the bandwidth is so and so the delay is 1 so now whatever that value to
feasible distance would be considered no so that’s feasible distance so whatever
that we’re out of 5 is sending draw 2 to the feasible distance of router 5 will
become the release the reported distance for outer two so router 2 is reported
distance is not a PHY feasible distance so feasible distance is being reported
so that becomes reported distance so all these devices reported distance is the
feasible distance for this device right now we need feasible distance and
reported distance for a reason you will see that so that’s what the reporter
distance reported distance is the distance feasible distance of the next
device which it’s reporting to you now when a router 2 makes the calculation
what did you do it did the same thing so let’s let’s do this again when router 2
is doing it now router 2 needs to look at the bandwidth
now between this and this it was reported 1 million kbps and 100,000 kbps
which lower Louis bandwidth so if you remember
the formula this is the lowest bandwidth 100000 is Louis bandwidth the hundred
thousand is nothing but 10 to the power of 5 so it’s 10 to the power 7 divided
by 10 to the power of 5 which is nothing but 10 to the power 2 which is hundred
plus what is the cumulative delay 100 plus 10 hundred and ten hundred and ten
tens of micro is 11 so 100 plus 11 is equal to 111 into two five six whatever
they get is this value 28 thousand four hundred 16 which is the feasible
distance for router to the same way here now we’re talking about 10 to the power
4 divided that is thousand if we divide this band apart you’ll get thousand and
cumulative delay is one thousand ten milliseconds microseconds rather 1010 is
hundred and one tens of microseconds 101 101 plus thousand is thousand 101 into
256 you would get this value 281 856 similarly for this because in this case
the lowest bandwidth is the same because this is 1 million whatever 1 Gigabit
Ethernet so it gets a FD of 3 0 7 2 now this 3 0 to 7 2 goes to the next
device as the reported distance this will go as a reported distance and this
would go as the reported distance again it would use the formula from now when
it comes here this bandwidth is Gigabit Ethernet again but the reporting
bandwidth is 100,000 which is lesser hundred thousand so it’s using the
formula now let’s do this year I’ll clear this again now when router 1 is
doing the calculation it’s getting a reported bandwidth of 100,000 its
bandwidth is one gigabit because hundred thousand is less it is going to use 100
thousand which is 10 to the power of 5 10 to the power 7 which is nothing but
hundred cumulative delay 10 100 120 120 is nothing but 12
112 into two five six is thirty thousand 976 that is the feasible distance
similarly the physical distance is two eighty four four one six again it is
reporting 10,000 and 100,000 so it will use 10,000 the calculation and it will
add all the delay until the end so so what happens when it when ERP sensor
updates it sends thousand ten thousand ten microsecond because that’s what
isn’t update but this is particular only to this interface right so then this
device will definitely know whatever the delay it is sending plus it would add
its own delay would get the cumulative delay so after that it does the feasible
distance which is two eight four four one six and this device gets two million
170 360 right now all three devices have a feasible distance depending on the
doors feasible distance so so router one has three routes to go to this network
okay so it looks at the least feasible distance the least feasible distance is
definitely 330 976 so this route becomes the successor
right the lowest feasible distance becomes the successor and it also in the
routing table that’s there’s something called feasible successor that means in
case this route ever fails there should be somebody for immediate backup so that
backup is immediate Antonius so to make somebody a feasible successor there is
one rule the rule is the reported distance of the other like in this case
the other two routes the reported distance should be less than the
feasible distance so reported distance of 281,000 which is not less than this
feasible distance so this will not become a feasible successor the reported
distance is 3072 so definitely this can become a feasible successor so this will
go into the routing table as a feasible successor that means when they
network ever goes down traffic will start going through this right that’s
feasible success and that’s why and this change over this switch over
so whenever a network goes down the routing know the time it takes for the
rounding able to get an alternative path is known as a convergence time rip is
very very slow it takes a very long time to converge or OSPF few seconds eSGR p
is instantaneous and that’s why ARP is so beautiful it’s very efficient because
instantaneously switch over because there is already a feasible successor in
its routing table now what happens if both of these like this the successor
and the feasible successor fails when that happens each GOP will run an
algorithm called as dual dua l what it does is because now it knows it when it
does the calculation it knew that there is a third route so what it does is it
sends a request and that device will say yes that particular route is available
so it sends a reply right this is dwell so it sends a dual request
once it confirms that it will take this whatever route is available it would put
that in the routing table and that takes about few seconds to do it so even if
you feasible distance fail or feasible successor fails yes you have to converge
is quite fast I mean maybe few seconds three seconds four seconds five taken
ten seconds whatever the time it takes it takes for this other neighbor the
Witch of a neighbor that is active the active neighbor to reply as soon as the
active neighbor replies it puts that interface or rather that route on the
routing table and we are back doing business as usual so these are the four
critical terms in ERP feasible distance reported distance successor and feasible
successes and I hope this made sense if not watch it again I’m sure
it would make sense how these successes and feasible successes are thank you so
much for watching we will be back very soon with the configuration part for
EIGRP thank you and see y’all back very very soon
buh-bye

Reynold King

40 Replies to “Free CCNA | EIGRP Introduction – Day 49 | 200-125 | Cisco Training”

  1. I'm on my 35th day of watching but I would like to thank you for continuing your videos, baraka allahou fik

  2. This is part of our FREE CCNA series. All videos in this series are still valid. If Cisco changes anything, we will be updating this series to be current. Stay tuned. Subscribe to be notified of new videos.

  3. OMG I'm late for a live video hi sir Imran how are you doing thanks for your free CCNA tutorial video, and to all everyone here watching videos how are you all.

  4. Finally waiting has ended.. got this video…
    Sir please upload videos as soon as possible.. I am eagerly waiting for my first job after completion

  5. Thank you so much for doing this. Keep it up and don't mind those who want videos every second. Take your time. You are doing great! Thanks again!

  6. Thanks man though you upload your videos very late its worth waiting. You deserve all the love from your admirers.

  7. Thank you sir… Please share some assignment after each video. So we will work on that.. It will also help us for practice..

  8. Hello Imran
    I would like to thank you very much for your priceless tutorial that helps every learner to get the maximum amount of knowledge. You are giving a rich material in a very simple way
    I also want to rise your attention for one thing. Would you please consider providing subtitles for your videos in Arabic and french. Very big audience in North Africa will appreciate that because a lot of people don't understand English
    Thank you and good luck.

  9. creating multi areas in ospf can avoid loop prevention.thank you Mr Imran you are the great inspiration for all the networkers.

  10. Area 0 makes the OSPF Hierarchy loop-resistant when combining multiple areas because of two important rules in OSPF:

    Having a backbone area and requiring all other areas connect to it creates a point to point topology which in itself is resistant to loops.

    Having ABRs reject any Type-3 LSA that is received over a non backbone area.

  11. OSPF does not use route poison but uses kind of split horizon because non- back bone area does not exchange LSA but has to go tru back bone area. Also the back bone area is the main means that prevents looping

  12. Hello everyone,
    First of all I want to thank Imran for his video series.

    Regarding this video I have one question (for anyone who knows the answer):
    Why does EIGRP use reported distance for selecting the feasible successor instead of simply going for the second best feasible distance ? ( the best FD already being the used as primary route )
    In the example topology the feasible successor is the slow 1,544 kbps line while it could have been a route with a bottleneck of 10,000 kbps AND the delay of the slower route is greater as well.

    Seems to me that EIGRP didn't select the best possible backup route in this case.
    I see no reason why EIGRP shouldn't base itself on feasible distance only, that way the feasible successor would be the best available route !

    Thanks in advance
    Best regards Ken

  13. EIGRP is not longer consider a Hybrid Routing Protocol, the term hybrid routing protocol is used in some older documentation to define EIGRP. However, this term is misleading because EIGRP is not a hybrid between distance vector and link-state routing protocols. EIGRP is solely a distance vector routing protocol; therefore, Cisco no longer uses this term to refer to it.

  14. Hello Mr. Imran.
    I'm your student and I really appreciate the content you share. However, the FD at R1 & R2 is (112×256)=28672 and not 30976

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