HP IPv6 6200yl, IPv6 2900, IPv6 5400zl, IPv6 3500yl manual FFFFFFFFFFFFFFF8FFFFFFFFFFFFFFFC

IPv6 Management Security Features

Authorized IP Managers for IPv6

Example. Figure 6-3 shows an example in which a mask that authorizes switch access to four management stations is applied to the IPv6 address: 2001:DB8:0000:0000:244:17FF:FEB6:D37D. The mask is:

FFFF:FFFF:FFFF:FFF8:FFFF:FFFF:FFFF:FFFC.

	1st	2nd	3rd	4th	5th	6th	7th	8th	Manager- or Operator-Level Access
	Block	Block	Block	Block	Block	Block	Block	Block
IPv6 Mask	FFFF	FFFF	FFFF	FFFF	FFFF	FFFF	FFFF	FFFC	The “F” value in the first 124 bits of the
IPv6 Address	2001	DB8	0000	0000	244	17FF	FEB6	D37D	mask specifies that only the exact value
									of each corresponding bit in an
									authorized IPv6 address is allowed.
									However, the “C” value in the last four
									bits of the mask allows four possible
									combinations (D37C, D37D, D37E, and
									D37F) in the last block of an authorized
									IPv6 address.

Figure 6-3. Example: Mask for Configuring Four Authorized IPv6 Manager Stations

Last block in Mask: FFFC

Last block in IPv6 Address: D37D

Bit Numbers

Bit Value

FFFC: Last Block in Mask

D37D: Last Block in IPv6 Address

Bit Setting:

Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit	Bit
15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0

F F F C

= 1 (On) = 0 (Off)

Figure 6-4. Example: How a Mask Determines Four Authorized IPv6 Manager Addresses

As shown in Figure 6-4, if you use a mask of FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFC with an IPv6 address, you can authorize four IPv6-based stations to access the switch. In this mask, all bits except the last two are set to 1 (“on”); the binary equivalent of hexadecimal C is 1100.

Therefore, this mask requires the first corresponding 126 bits in an authorized IPv6 address to be the same as in the specified IPv6 address: 2001:DB8:0000:0000:244:17FF:FEB6:D37C. However, the last two bits are set

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