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LevelOne GTL-2691 User Manual

Page 584

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| IP Configuration

Setting the Switch’s IP Address (IP Version 6)

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EUI-64 (Extended Universal Identifier) – Configures an IPv6

address for an interface using an EUI-64 interface ID in the low

order 64 bits.

When using EUI-64 format for the low-order 64 bits in the host

portion of the address, the value entered in the IPv6 Address

field includes the network portion of the address, and the prefix

length indicates how many contiguous bits (starting at the left)

of the address comprise the prefix (i.e., the network portion of

the address). Note that the value specified in the IPv6 Address

field may include some of the high-order host bits if the

specified prefix length is less than 64 bits. If the specified prefix

length exceeds 64 bits, then the bits used in the network portion
of the address will take precedence over the interface identifier.

IPv6 addresses are 16 bytes long, of which the bottom 8 bytes

typically form a unique host identifier based on the device’s MAC

address. The EUI-64 specification is designed for devices that

use an extended 8-byte MAC address. For devices that still use a

6-byte MAC address (also known as EUI-48 format), it must be

converted into EUI-64 format by inverting the universal/local bit

in the address and inserting the hexadecimal number FFFE

between the upper and lower three bytes of the MAC address.
For example, if a device had an EUI-48 address of 28-9F-18-1C-

82-35, the global/local bit must first be inverted to meet EUI-64

requirements (i.e., 1 for globally defined addresses and 0 for

locally defined addresses), changing 28 to 2A. Then the two

bytes FFFE are inserted between the OUI (i.e., organizationally

unique identifier, or company identifier) and the rest of the

address, resulting in a modified EUI-64 interface identifier of 2A-

9F-18-FF-FE-1C-82-35.

This host addressing method allows the same interface identifier

to be used on multiple IP interfaces of a single device, as long as

those interfaces are attached to different subnets.

Link Local – Configures an IPv6 link-local address.

The address prefix must be in the range FE80~FEBF.

You can configure only one link-local address per interface.

The specified address replaces a link-local address that was

automatically generated for the interface.

IPv6 Address – IPv6 address assigned to this interface.

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To configure an IPv6 address:

1.

Click IP, IPv6 Configuration.

2.

Select Add IPv6 Address from the Action list.