ZyXEL Communications VMG1312-B Series, Руководство пользователя

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Appendix E IPv6
VMG1312-B Series User’s Guide
353
Subnet Masking
Bot h an I Pv6 address and I Pv6 subnet m ask com pose of 128- bit binary digit s, which are divided
int o eight 16- bit blocks and writ t en in hexadecim al not at ion. Hexadecim al uses four bit s for each
charact er ( 1 ~ 10, A ~ F) . Each block’s 16 bit s are t hen represent ed by four hexadecim al
charact ers. For exam ple, FFFF: FFFF: FFFF: FFFF: FC00: 0000: 0000: 0000.
Interface ID
I n I Pv6, an int erface I D is a 64- bit ident ifier. I t ident ifies a physical int erface ( for exam ple, an
Et hernet port ) or a virt ual int erface ( for exam ple, t he m anagem ent I P address for a VLAN) . One
int erface should have a unique int erface I D.
EUI-64
The EUI - 64 ( Ext ended Unique I dent ifier) defined by t he I EEE ( I nst it ut e of Elect rical and Elect ronics
Engineers) is an int erface I D form at designed t o adapt wit h I Pv6. I t is derived from t he 48- bit ( 6-
byt e) Et hernet MAC address as shown next . EUI - 64 insert s t he hex digit s fffe bet ween t he t hird and
fourt h byt es of t he MAC address and com plem ent s t he sevent h bit of t he first byt e of t he MAC
address. See t he following exam ple.
Identity Association
An I dent it y Associat ion ( I A) is a collect ion of addresses assigned t o a DHCP client , t hrough which
t he server and client can m anage a set of relat ed I P addresses. Each I A m ust be associat ed wit h
exact ly one int erface. The DHCP client uses t he I A assigned t o an int erface t o obt ain configurat ion
from a DHCP server for t hat int erface. Each I A consist s of a unique I AI D and associat ed I P
inform at ion.
The I A t ype is t he t ype of address in t he I A. Each I A holds one t ype of address. I A_NA m eans an
ident it y associat ion for non- t em porary addresses and I A_TA is an ident it y associat ion for t em porary
addresses. An I A_NA opt ion cont ains t he T1 and T2 fields, but an I A_TA opt ion does not . The
DHCPv6 server uses T1 and T2 t o cont rol t he t im e at which t he client cont act s wit h t he server t o
ext end t he lifet im es on any addresses in t he I A_NA before t he lifet im es expire. Aft er T1, t he client
sends t he server (
S1 ) ( from which t he addresses in t he I A_NA were obt ained) a Renew m essage. I f
FF08:0:0:0:0:0:0:0
FF09:0:0:0:0:0:0:0
FF0A:0:0:0:0:0:0:0
FF0B:0:0:0:0:0:0:0
FF0C:0:0:0:0:0:0:0
FF0D:0:0:0:0:0:0:0
FF0E:0:0:0:0:0:0:0
FF0F:0:0:0:0:0:0:0
Table 128 Reserved Mult icast Address ( cont inued)
MULTICAST ADDRESS
M AC 00 : 13 : 49 : 12 : 34 : 56
EUI - 6 4 0 2 : 13 : 49 : FF : FE : 12 : 34 : 56