The second step consists of setting the seventh but of the 64 bit address this but identifies the 40
A.
But MAC addresses uniqueness or lack there of an ethernet address has two significances.
It's either globally managed or locally managed globally managed means that you use the Venda MAC address
locally managed means that you rewrite the MAC address with your own value.
In other words you change the MAC address to a locally significant value.
So that's 7.
But all the usual bet is set to either one which means the address is unique or set to zero meaning
the address is not unique.
Now in this example let's assume that we're using a vendor MAC address.
So in other words this but get sick to one if you have a binary value of six zeros followed by one followed
by zero.
Converting that back to hexadecimal will give you a value of zero.
So just to reiterate you have a hexadecimal value of 0 0 that's converted into binary the seventh binary
but is either set to 1 or 0 depending whether its globally unique or not globally unique.
That is then converted back to hexadecimal.
So once again the V-6 aggregate of all global unicast address is 128 bits in length half of the address
is the network prefix which is 64 bits and half of the addresses the interface identify which is 64
bits the network prefix is broken up into two major parts.
You have the global routing prefix which is used for the public apology.
In other words the Internet and the subnet ID which is used for the site topology.
In other words the subnet portion of the address would be used to create subnets within an enterprise
or within an organization or within a site.
It's 16 but same length.
That means that a service provider will give you a slash 48 subnet for every site organization that
you manage that gives you 16 bits for subnets which allows you to create 65000 536 subnets within your
organization from one subnet given to you by the service provider.
You would continue using a 64 mosque on every link no matter whether it's a point to point link or anything
that subnet the service provider network consists of a slush Forty-Eight network your internal networks
consist of flesh 64 subnets.
So once again the ISP will allocate forty eight subnet you will allocate a slice 64 subnet to each interface.
Once again no need to do complicated submitting all your subnets are slash 64 was from the slash forty
eight that you were allocated by your service provider.
Remember there is no net all internal addresses within your organization by using these IP V-6 aggregated
all global unicast addresses which are the equivalent of public IP addresses with an IP version 4 the
version 6 address is actually broken up into more fields.
I wouldn't worry too much about this but I just want to show you the actual format for this aggregated
global unicast address.
You firstly have the interface identify which has 64 bits in length.
I've explained that that identifies the equivalent of the host portion in an IP version 4 address.
The next part is the SLA ID or site level aggregation identifier.
This is like your subnet identifier which represents subnets within an organization its 16 bits in length
giving you over 65000 subnets to use within a site or an organization.
Then you have the ID which is the next level aggregation identifier.
And this will be used by your ISP.
They are a reserved bits which are not currently used and then you have the TSA ID which is the top
level aggregation identifier used by various regional Internet registries around the world the Internet
registries will then assign TLM IDs to large eyes is specifically transit providers and exchanges.
And then lastly we have the format prefix which is set to 001.
Once again this portion of the address is the public typology and we are not particularly concerned
with that in this course within enterprises or sites we would have the subnet ID which is used for site
typology.
And then once again the interface ID which is used as the host portion of an IP address.
The advantage of this IP V-6 address layout is aggregation.
It allows for aggregation or summarization of addresses within the global Internet.
Just be aware as well that every IP V-6 interface contains at least one loopback address which is colon
colon one slash 128 optioning interfaces might include multiple unique local and global addresses.
This is an important concept in IP version for on a Cisco router.
You can only allocate a single IP address as the primary IP address on that interface.
All subsequent IP addresses are configured a secondary IP addresses.
However an IP version 6 you can configure multiple primary IP addresses on an interface that's quite
a major change from kabillion for.
I'll show you in a moment when you enable IP V-6 on a Cisco routers interface multiple IP addresses
are automatically allocated to that interface.
And once again the whole reason for this address layout is aggregation and summarization.
So let's look at global aggregation in Internet registry.
We'll have for instance a slashed 16 address.
So 2001 colon colon slash 16 a slash 32 subnet is allocated to an ISP.
So in this example 2001 Carlon one two three four colon colon slash 32 is allocated let's say for instance
to this ISP the service provider can then allocate a slash 48 submit to an organization or enterprise.
So in this example let's assume that 2001 Colan one two three four colon one colon colon slash 48 is
allocated to customer.
A customer can then subnet the slash 48 to slash 64 submits and allocate those subnets to every interface
within the organization.
So notice 2001.
2001 one two three four Colan one which is a slash Forty-Eight subnet.
The Enterprise was allocated is submitted again to Colon to Colon colon.
In other words a slash 64 subnet is allocated to this interface and then notice over here three is allocated
to this interface all link just to help you once again with these addresses.
Remember these values on hexadecimal a single value in hex equates to four binary bits.
So we have one two three four hexadecimal values for hex values times for Issue 16 binary.
That's.
So this is actually a 16 bit address.
Hence slash 16 by the same token here.
Remember this is 16 and this is 16 set of values between the colons are 16 bit values so 16 for 16 gives
you 32.
So hence slash 32.
Once again here we have another valley between Cullens.
So it's 16 16 and 16.
Remember leading zeros can be dropped in an address.
So that gives you 48 bits in 48 and lost the this address there is 1 2 3 4 Baillieu's between Colon's
leading zeroes have been dropped.
So that's four times sixteen giving you slash 64.
I hope that helps you decipher the address a little easier.
Please note on these subnets we have not displayed the host portion of the address.
Now without further ado let's set up a basic IP version 6 network.
In this example I have Route 1 and route to both route as have a fost Ethan and interface of one's network
and the cost Ethan and interface is going to be 2001.
Column One column one code on one router to use force Ethernet subnet is going to be 2001 Carlon one
Kolin one code and three the rod is connected by a serial link and the subnet is going to be two thousand
in one color and one color in one color.
Notice once again the subnet mask is always Sless 64 on all subnets.
OK so in Rato one I'm going to break out of the initial configuration dialog
get into global config mode it gives the Rodda a name and then I'm going to enable IPV sake's uni cost
routeing so that we can run the B-6 on this Rodda and then I'm going to go into it 0 0 Foster Ethan
ethernet interface and give it an address so IP V-6 and notice there are a lot of options here.
But I'm going to specify a dress and then I'm going to specify an IP V-6 address.
So 2001
and in this case I'm going to give the interface an address of one that's as simple as that to configure
an IP version 6 address on a router.
This portion is the network portion.
And notice we've got code on Colan So there are a bunch of zeros not displayed here.
And we ending in a one and then I can no shut the interface and as you can see the interfaces come up
so knock on top do paying two thousand and one
and paying the kids race.
And as you can see the ping is successful on the cereal zero interface.
I can do the same thing IPV six the drapes 2001
and on this side I'm giving in an address of Colan one.
And on this side I'm going to give an address of colon to some rodded to do the same thing.
Enable IPV six unit cost routing and then on it seriously I Ciro give it an IP V-6 address 2001
no shut the interface and 0 0 0 given an address
and I shut that interface.
So hopefully now from rhotic to I should be able to ping roaded 1.
That doesn't work because I forgot to note the interface on the side so I'll shut it and go back to
reality.
Well let's see if that pings succeeds this time.
Get into face came up and as you can see the pink succeeded.
It's as simple as that to configure IP addresses on a Cisco router.
Now on the first effective interface I could give it another IP address so I could say IPV six trace
and let's just be lazy.
It's given an address of 2001 column called on one 64.
And as you can see the rod has accepted that address on the right.
I could not ping 2001.
Carl On-Call on one and as you can see the thing succeeds.
I could go back into the interface and give it an address as follows.
IPV 6 address and it's a 2001 Carlon to Colon colon.
Notice it gives you the option of link local address but we don't want to do that.
Let's go for Slash 64.
Notice please I haven't cooked a host portion on this address.
Just specify the network portion and now what I can do is I can specify UI 64 and hit enter.
So we are going to use the Mac address as part of that address.
So now I can type the command show to run interface sera sera to show you the configuration.
And as you can see there's no provision for address configured on this interface.
There are only IP version 6 addresses and there are three IP version 6 addresses that we have manually
configured.
I couldn't up show interface 0 0 the MAC address of this interface is C 4 0 1 0 F E 8 followed by four
zeros.
So the Venda portion of this address is see 4 0 1 0 F and the unique portion is e-rate followed by four
zeros.
So just to display that nicely.
I'm going to say show interface 0 0 Why include a set.
Only shows that Mac address in the output.
And there it is.
And then I'm going to show IPB 6 interface 0 0 and only include the addresses that we configured and
the other three IP addresses we can take it on the interface so noted here please.
We'll start from the right inside the unique portion of the MAC address is 8 followed by four zeros.
There it is in the IP address.
Remember leading zeros can be dropped.
So this zero represents those four zeros the eight is the right over there F F F E has been inserted
in the address to make it 64 bucks and then notice the remaining portion is C 4 0 1 0 F which is represented
here as C6 0 or 1 if once again leading zeros can be removed.
Notice the zero in front of this f has been removed.
See 4 0 1 has been converted to see 6 0 1 because the 7th but has been changed to a one to represent
that this mac addresses globally unique.
So notice a IP address is derived from the MAC address by using the UI representation of the MAC address.