IPv6 Stuff

IPv6 Training (Cisco) – How to Convert Hexadecimal to Decimal
By Charles E Ross

I wrote this article because lately I’ve been receiving a lot of emails from IPv6 enthusiasts asking me the question “How do I convert Hexadecimal to Decimal without using a calculator?”

Now, although the procedure may sound hard to perform, it’s rather easy to do; all you have to do is perform the following steps:

Steps:
1. Locate the “last digit” of the hexadecimal number that you want to convert. (the last digit of a hexadecimal number is the digit that is farthest to the right).

2. Once, you have identified the last digit; you will then multiply the “last digit” with (16^0). In other words, in step number two; you are going to multiply the value of the “last digit” with (16 to the power of zero).

Example: “last digit value” x (16^0) = “last digit value”

Note, that the power of 0 of any number is always 1.

Once, you have performed the formula on the last digit, write down the result; and then move on to the previous digit on the (your) left.

3. Each time you move on to a previous digit, you’ll need to increase the power (16^X) of the formula by 1 before performing the formula on that digit.

4. Simply perform the formula (digit value x (16^X) on all of the remaining digits until all digit results have been written down.

5. Then add (sum) all of the written down (stored) results together to get the final answer number.

Here’s an example: We are converting the HEXADECIMAL number FB8 to DECIMAL(the number 8 is the “last digit”)

1. 8 x (16^0) = 8
2. B x (16^1) = 176
3. F x (16^2) = 3840
4. 8 + 176 + 3840 = 4024

So, the decimal equivalent of the hexadecimal number FB8 is 4,024.

Here’s another example: We are converting the HEXADECIMAL number 7747 to DECIMAL (the number 7 is the “last digit”)

1. 7 x (16^0) = 7
2. 4 x (16^1) = 64
3. 7 x (16^2) = 1792
4. 7 x (16^3) = 28672
5. 7 + 64 + 1792 + 28672 = 30535

So, the decimal equivalent of the hexadecimal number 7747 is 30,535.

Below is a quick reference of the powers of 16:

16^0 = 1
16^1 = 16
16^2 = 256
16^3 = 4096
16^4 = 65536
16^5 = 1048576

I invite you to visit my website were you’ll find the latest information regarding Cisco IPv6 Design and Implementation Techniques.

To your success,

Charles Ross, CCNP #CSCO10444244 is the owner of Ittechtips.com; where you’ll find free comprehensive information and videos about IPv6 technology and how it works with Cisco Systems technology.

Sign-Up for “18 Free Videos” that will teach you IPv6 Address Representation In Under 10 Minutes! And, also learn more about the new “Cisco IPv6 Video Accelerated Training Course” at his website.

http://www.ciscoipv6ittechtips.com

Article Source: http://EzineArticles.com/?expert=Charles_E_Ross
http://EzineArticles.com/?IPv6-Training-(Cisco)—How-to-Convert-Hexadecimal-to-Decimal&id=1373060

IPv6 Training (Cisco) – the Difference Between Stateful and Stateless DHCP
By Charles E Ross

Well, instead of me just jumping right into explaining the difference between Stateful and Stateless DHCP. I’m going to slow down just a bit and briefly explain DHCP first.

DHCP stands for Dynamic Host Configuration Protocol, this client / server protocol has been around for awhile now, and is regually implemented on IPv4 networks. IPv4 DHCP, is explained in RFC 2131 and IPv6 DHCP is explained in RFC 3315. But, in a nutshell; network adminstrators use DHCP to provide a framework that is used by networked devices (DHCP clients) to obtain various necessary parameters from DHCP Servers so the DHCP clients can operate in an Internet Protocol (IP) network. Now when it comes to DHCP for IPv6 (RFC 3315), there are two ways DHCPv6 can be implemented, either Stateful or Stateless. Stateful DHCP is centrally managed on a DHCP server(s); and the DHCP clients use Stateful DHCP to obtain an IP address(es) and other useful configuration informaiton from the DHCP server(s).

But, Stateless DHCP on the other hand; means the DHCP server(s) is not required to store any dynamic state information on the DHCP server(s) about any indivisual DHCP clients. Instead, the DHCP clients autoconfigure their own IP address(es) based on router advertisments. So, with Stateless DHCP, the DHCP clients don’t use the DHCP server(s) to obtain IP address(es) information, they use the DHCP server(s) to obtain the other useful configuration informaiton (like the address(es) of DNS servers).

Currently, Cisco recommends that you use Stateless DHCP instead of Stateful DHCP when implementing and deploying IPv6 networks; because, Cisco Routers are not designed to act as Stateful DHCPv6 servers. But, if you need to implement Stateful DHCP on your IPv6 network; Cisco makes a product named Cisco Network Registar (CNR) that can help you out a lot. I invite you to visit my website were you’ll find the latest information regarding Cisco IPv6 Design and Implementation Techniques.

To your success,

Charles Ross, CCNP #CSCO10444244 is the owner of Ittechtips.com; where you’ll find free comprehensive information and videos about IPv6 technology and how it works with Cisco Systems technology.

Sign-Up for “18 Free Videos” that will teach you IPv6 Address Representation In Under 10 Minutes! at his website.

http://www.ciscoipv6ittechtips.com

Article Source: http://EzineArticles.com/?expert=Charles_E_Ross
http://EzineArticles.com/?IPv6-Training-(Cisco)—the-Difference-Between-Stateful-and-Stateless-DHCP&id=1325524

Cisco IPv6 Training – IPv6 Requesting Router (RR) Configuration
By Charles E Ross

Now you the first thing that you need to remember, is that the Requesting Router or RR is in most cases located at the customer’s location (premises); it’s the router that the customer (Site) has either purchased or has been given to them by their ISP.

In real world situations, the RR has 2 main responsibilities; obtaining the Global IPv6 prefix information (configurable parameters) from the ISP’s Delegating Router (DR); and then passing that Global IPv6 prefix information (configurable parameters) along through out the customer’s location (Site) by using Router Advertisements (RA).

Now, in order for you to configure a Cisco router’s upstream interface to act like a Requesting Router (DHCP client) you’ll need to perform these 5 steps:

1. Router>enable
2. Router#configure terminal
3. Router(config)#interface type number
4. Router(config-if)#ipv6 address autoconfig [default]
5. Router(config-if)#ipv6 dhcp client pd prefix-name [rapid-commit]

Steps Explained:

Step #1: Router>enable

Puts the router into Privileged Exec mode

Step #2: Router#configure terminal

Puts the router into Global Configuration mode

Step #3: Router(config)#interface serial 0/0

Allows, the RR to enter interface configuration mode for the serial 0/0 interface.

Step #4: Router(config)#ipv6 address autoconfig default

Allows, the RR router’s serial 0/0 interface to automatically configure its own IPv6 address(es) by using Stateless Autoconfiguration.The word “default” is used to tell the serial 0/0 interface to install a default route into the RR’s routing table; the default route indicates the upstream interface (serial 0/0) and the ISP’s Delegating Router’s interface.

Step #5: Router(config-if)#ipv6 dhcp client pd comcast-dhcp-prefix rapid-commit

Enables, the RR router’s serial 0/0 interface to begin acting as a DHCPv6 client; and also forces the interface to start requesting an IPv6 Prefix(es) from the ISP’s Delegating Router. The word “rapid-commit” is telling the interface (serial 0/0) to use the DHCPv6 two-message exchange method to ask for the IPv6 Prefix(es).

Now, just in case if you were wondering, the words “comcast-dhcp-prefix” used in the command is the name of the prefix.

I invite you to visit my website were you’ll find the latest information regarding Cisco IPv6 Design and Implementation Techniques.

To your success,

Charles Ross, CCNP #CSCO10444244 is the owner of Ittechtips.com; where you’ll find free comprehensive information and videos about IPv6 technology and how it works with Cisco Systems techonoloy.

Sign-Up for “18 Free Videos” that will teach you IPv6 Address Representation In Under 10 Minutes!!!! at his website.

http://www.ciscoipv6ittechtips.com

Article Source: http://EzineArticles.com/?expert=Charles_E_Ross
http://EzineArticles.com/?Cisco-IPv6-Training—IPv6-Requesting-Router-(RR)-Configuration&id=1335012

IPv6 Training (Cisco) – Assigning an IPv6 Address to an Interface
By Charles E Ross

Well, to make a long story short; the Interface command “ipv6 address” is used to assign (configure) a layer 3 IPv6 address to a Cisco router’s interface. Currently, there are five different ways the “ipv6 address” command can be used.

View Examples Below:

1. Syntax: Router(config-if)#ipv6 address ipv6 address/prefix-length

Example: Router(config-if)#ipv6 address 2001:100:100:100::1/64

2. Syntax: Router(config-if)#ipv6 address ipv6 prefix/prefix-length anycast

Example: Router(config-if)#ipv6 address 2001:0DB8:1:1::/64 anycast

3. Syntax: Router(config-if)#ipv6 address autoconfig [default]

Example: Router(config-if)#ipv6 address autoconfig

4. Syntax: Router(config-if)#ipv6 address ipv6 prefix/prefix-length eui-64

Example: Router(config-if)#ipv6 address 2001:100:100:100::/64 eui-64

5. Syntax: Router(config-if)#ipv6 address ipv6 link-local address/prefix-length link-local

Example: Router(config-if)#ipv6 address FE80::260:3EFF:FE11:5770/64 link-local

IPv6 Address Command Examples Explained:

1. Syntax: Router(config-if)#ipv6 address ipv6 address/prefix-length

Example: Router(config-if)#ipv6 address 2001:100:100:100::1/64

The first example is using the “ipv6 address” command to assign (configure) an IPv6 Global Unicast Address (GUA) to an interface. Notice, in the first example the “ipv6 address” command is requiring the complete IPv6 address and the prefix-length. The prefix-length (/64) is indicating how many high order bits are being used for the network portion of the GUA.

2. Syntax: Router(config-if)#ipv6 address ipv6 prefix/prefix-length anycast

Example: Router(config-if)#ipv6 address 2001:0DB8:1:1::/64 anycast

The second example is using the “ipv6 address” command to assign (configure) an IPv6 Anycast Address to an interface. Notice, in the second example the “ipv6 address” command is only requiring the IPv6 prefix (network portion) of an IPv6 address and the prefix-length, followed by the word “anycast”.

3. Syntax: Router(config-if)#ipv6 address autoconfig [default]

Example:Router(config-if)#ipv6 address autoconfig

The third example is using the “ipv6 address” command to make the interface in question automatically autoconfigure itself with an IPv6 address using stateless autoconfiguration. You can also use the keyword “default” to make the interface install a default route. But remember, the keyword “default” can only be used on one interface.

4. Syntax: Router(config-if)#ipv6 address ipv6 prefix/prefix-length eui-64

Example: Router(config-if)#ipv6 address 2001:100:100:100::/64 eui-64

The fourth example is using the “ipv6 address” command to assign (configure) an IPv6 Global Unicast Address (GUA) to an interface. But, unlike the first example; this example is requiring that the “ipv6 address” command use the IPv6 prefix (network portion) of an IPv6 address and the prefix-length; followed by the word “eui-64″. In other words, in this example, the interface is going to assign (configure) a GUA to itself; by combining the IPv6 prefix (network portion) which are the first sixty four (/64) high order bits; with the remaining sixty four low-order bits which are the EUI-64 Interface Identifier. The EUI-64 Interface Identifier, is actually the interface’s layer 2 address (MAC Address) that has been modified into EUI-64 format.

5. Syntax: Router(config-if)#ipv6 address ipv6 link-local address/prefix-length link-local

Example: Router(config-if)#ipv6 address FE80::260:3EFF:FE11:5770/64 link-local

The fifth example is using the “ipv6 address” command to assign (configure) a specific (certain) layer 3 Link-Local Address to an interface. Notice, that in the fifth example, the “ipv6 address” command is requiring the entire IPv6 link-local address and the prefix-length, followed by the word “link-local”. The “link-local” word is telling the interface, to configure (assign) the link-local address (FE80::260:3EFF:FE11:5770) to the interface and also overwrite any link-local address that may have been configured (assigned) earlier “automatically” from the interface’s MAC Address.

I invite you to visit my website were you’ll find the latest information regarding Cisco IPv6 Design and Implementation Techniques.

To your success,

Charles Ross, CCNP #CSCO10444244 is the owner of Ittechtips.com; where you’ll find free comprehensive information and videos about IPv6 technology and how it works with Cisco Systems technology.

Sign-Up for “18 Free Videos” that will teach you IPv6 Address Representation In Under 10 Minutes!! at his website.
http://www.ciscoipv6ittechtips.com

Article Source: http://EzineArticles.com/?expert=Charles_E_Ross
http://EzineArticles.com/?IPv6-Training-(Cisco)—Assigning-an-IPv6-Address-to-an-Interface&id=1323225