Everyone, so now we are going to discuss the SPF mantra, if you remember, each routing protocol is
having different metrics like before we discuss reports, having the whole corn and SPF is having that
metric as a cause and with all as having the bandwidth and delay.
We did not cover the year GDP.
After we finished your SPF, we are going to look very to be also.
So now we need to check.
We are seeing SPF metric is cost.
So we need to remember cost is equal to the reference bandwidth by divided by interphase bandwidth.
This is a formula given by Cisco and what we can say.
First thing we need to remember oil of might, costs and causes equal to reference bandwidth divided
by interface bandwidth.
This point we need to remember in the will you what is always free of matter.
So we need to see costs and they will what its cost is equal to a reference bandwidth divided by interface
bandwidth for which interface you want to calculate the bandwidth that interface bandwidth.
What we have, we will divide that one and reference bandwidth is nothing but 100 and BP is inversely
best out.
So this point also we need to remember in the score out define default value for that difference.
Bandwidth 100Mbps hundred megabyte.
That is nothing but tend to boroff ed.
OK.
So what we can say is we use metric called cost, which is based upon the bandwidth of the interface,
and we can calculate this by using the formula causes equal to reference bandwidth by interphase bandwidth
and reference bandwidth is the default value on the quarter that is hundred megabyte.
And it is nothing but time to Parafield, and we can divide that into part of it with the reference
into part of aid, with the interface bandwidth to get that value and the lower the cost, the better
the part.
As we discussed, whenever we have the lower metric, we will prefer that part and the router, which
is having the low cost that value is going to prefer and that is going to be stored in the routing table.
If you have the two part with the equal cost, the noise you have is going to do that load balancing.
Example if you have like this scenario, if you want to go from here, example R1 two are do you want
to go to R1 to R2?
You have to part one is this one one is this one?
Both are having same cost example.
This one is also having one cost.
This one also having one cost.
This is a fast internet zero by zero.
This is a fast internet, zero by one.
This is also zero by zero and this is the opposite of zero by one.
So what SPF will give if we, if we have the equal cost would link, then he will send one packet from
here, one packet from here.
They will do that load balancing or SPF will do that.
Equal cost load balancing.
Equal costs, load balancing.
Equal cars load balancing means we will have the same costs if you have one here, here should be one,
if you have been here, here should be 10, but you need to remember e.g. AARP is doing equal as well
as unequal, unequal and equal.
So even if you have that unequal cost or equal cost, they will do that load balancing in their geography.
But in ways they will do only for that equal costs.
We need to remember this one.
OK, so now what we are seeing, if two part is equal cost, the noise is going to use the boat, but
they will do that load balancing among them 50 percent, 50 percent off it will go up.
15 percent traffic will go from the below.
So this one, we understand, we understand the formula.
Now we have the idea and we need to remember this box.
This box is very simple.
Internet link, OK, internet link via a fast internet link.
We have clear link.
We have Gigabyte Link.
We have 10 gigabyte, 40 gigabyte one gigabyte.
So this is a default value of the interface.
If we are using internet, then we will have that 10 megabyte.
If we are using the fastest, we will have the 100 megabyte.
If we are using the serial, then we will have one, five or four cables.
If we are using the Gigabyte link, then we have one GB as if we are using 10 gigabyte link.
Then we have the 10 dubious speed of the bandwidth.
This value we need to remember so we can easily calculate if we did not remember, we can get this value
and so no need to worry.
If we go inside that Outtara and we check the interface, we can get this value on.
So I will show you how we can get that value.
Now just we need to remember one megabyte is nothing.
But then two part of six, OK, one megabyte is nothing, but then to borrow six.
Now what I will do, I will go any interface.
I will go in the other one.
OK.
In Ottawa, and I will check the interface bandwidth.
What is the interface bandwidth in that one?
I want to verify that one.
So what I will do, I read your interface was internet zero zero.
OK.
Islature interface fast.
Internet zero by zero.
So if you see this is the bandwidth.
OK, this is the bandwidth.
What is the bandwidth is written here.
Here, bandwidth is nothing, but BW is equal to one two three four five.
OK, then two four five.
And if you see kilobyte, if I want to remove kilobyte, that will be 10 to one of three.
So Total will return to par four eight five six seven eight.
So bandwidth for that fast, fast internet is how much time to traffic.
Then, to paraphrase, it is nothing but 10 to 100 megabyte also, so you can write 100.
Let me show you here.
In other words, what we wrote this one hundred megabytes, if you see here, then topography six is
nothing but one megabyte, then topography six is one megabyte.
So what value we have here in the router just now, what we observe, we have 10 topography and we have
two part of three.
So we are told we have to eight this value just now.
Check how we check.
We have five zero one two three four five and cables.
So if I want to remove cables, I need to add more three zero.
So if I three zero one two three four five six seven eight or ten to provide this value, is that what
is this value?
This value is Firefox Internet zero zero four two two zero zero zero.
That is nothing but this one if I want to remove.
If I want to convert this into 10 to ward off zero how I can convert, I write 100 megabits per second.
I want to remove the megabyte Busacca.
And so over eight hundred when I want to remove this one, I need to write in two part of six, so I
will write in 220 part of six.
So six.
And this tool.
So 10 tuberous to entertain part of six.
So what is this value?
10.
Topography eight.
That means this is it.
And topography.
This is nothing what topography.
And if you see, just now we check this one out of twenty eight.
So just we are comparing we are seeing that this value we need to remember if we did not remember,
we can log in to that outline.
We can check the interface and we know that into 100 megabyte, there is nothing but time to Parafield.
OK, this value just showing you.
But if you remember directly, no need to check and do calculation.
Now you know what is our farm cost is equal to rephrase when we reference bandwidth always is called
into part of aid.
We write in topography, divide by interface, band, whatever interface you.
To calculate the cost that interface, bandwidth meaning to the idea.
So this interface example, this interface.
So this is the 100 megabytes, 100 megabytes we thought we can write hesitant to provide.
Right.
Just now, we can do calculations over lightning topography.
This one, this one can sell, so you will have one.
So cost will be one.
So this is the one.
OK.
This is day one.
Now we will do for the internet link.
We will do for the entire Middle Eastern.
Link is having an MVP.
So sees equal to 10 megabytes this value.
Or let me take both.
What we are seeing costs us is equal to reference bandwidth divided by interface, bandwidth, interface,
bandwidth and Cizik, although we can say and to part of it, OK.
And the interface bandwidth is to Prof.
Sermon.
So when we calculate we have 10, so cost will return.
If you are confused, we can write this well.
So this is 100 megabytes per second and this one is it 10 megabytes for second.
So this this cancels, so you have only 10 or 10 will be that cost for internet link?
OK.
Let me show you here this one.
I am seeing this one 10 megabytes references.
Nothing worked in topography and topography.
And also we can write like A and B B this one.
Also this one, this one the same.
So I divide this value with the 100 and.
So we have only ten here.
So this is a course for the internet link.
Same thing we can do for this one, this one, this one.
But easy.
Just remember, internet is having costs in the SPF in SPF internet link is having that cost them fast.
Internet is having the one and the cereal is having sixty.
For all of our interface about means more than fast internet means Google.
You, Google and Google for all are having one.
So just remember Cereal 64, Internet 10 and all of that will have one.
If you remember also that OK, in Interview of the Ox, you can calculate or you can just tell that
cost is equal to the reference bandwidth by interface bandwidth references.
And I think we tend to part of it.
Interface means this value, or we can check that out just now.
What we check this one game is three zero KiloByte Kilo and the Boroff three.
So this is Fi M3, that means 10 to part of it.
So now we will do one lap so we can verify that one also, OK?
We will do one lap, so we will have that idea.
This is a pity.
And now we will do the lap.
In that scenario, we will take one water or 3.0 we will use.
So let me stop this recording.