Tài Liệu IPV6 Tiếng Việt

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Mc lc Gii thiu IPv6 ...................................................................................................................... 2

i vi c gi ...................................................................................................................... 2

iu kin tin ................................................................................................................... 3

Tng quan v IPv6 ................................................................................................................ 3

Ti sao phi c phin bn IP mi? .................................................................................... 3

Ti sao khng phi l IPv5? .............................................................................................. 4

Lch s ngn gn .............................................................................................................. 4

c im ca IPv6 ................................................................................................................ 5

Cc ch nh v trong IPv6 ................................................................................................ 7

Ch nh v Unicast trong IPv6 ..................................................................................... 7

Ch nh v Multicast trong IPv6 ................................................................................... 8

Ch nh v Anycast trong IPv6..................................................................................... 8

Kiu & nh dng a ch trong IPv6 ...................................................................................... 9

H thng s thp lc phn trong IPv6 ............................................................................... 9

Cu trc a ch trong IPv6 .............................................................................................. 10

Interface ID trong IPv6 .................................................................................................... 11

a ch Unicast ton cu trong IPv6 ................................................................................. 12

a ch Lin kt-Ni b (Link-Local) trong IPv6 ................................................................ 12

a ch Duy nht-Ni b (Unique-Local) trong IPv6 ......................................................... 13

Phm vi ca cc a ch Unicast trong IPv6 ....................................................... 13

Cc a ch c bit trong IPv6 ............................................................................................ 14

a ch Multicast dnh ring cho cc Giao thc nh tuyn .............................................. 14

a ch Multicast dnh ring cho cc Router/Node .......................................................... 15

Cc trng Header trong IPv6 ............................................................................................ 15

Header c nh (Fixed Header) trong IPv6 ...................................................................... 15

Extension Header trong IPv6 .......................................................................................... 17

Giao tip trong IPv6 ............................................................................................................ 18



Giao thc pht hin ln cn (Neighbor Discovery Protocol) trong IPv6 ............................ 19

Subnetting trong IPv6 .......................................................................................................... 20

Chuyn tip t IPv4 ti IPv6 ............................................................................................... 20

Dual Stack Routers ......................................................................................................... 21

Tunneling ........................................................................................................................ 21

NAT Protocol Translation ................................................................................................ 22

Kh nng lu ng ca IPv6 .............................................................................................. 22

Qu trnh hot ng ca Mobility ca IPv6 ...................................................................... 23

S ti u ha tuyn ca IPv6 .......................................................................................... 25

nh tuyn (Routing) trong IPv6 .......................................................................................... 25

Cc giao thc nh tuyn trong IPv6 ............................................................................... 26

Cc giao thc c thay i h tr IPv6 .................................................................... 26

Tng kt v IPv6 ................................................................................................................. 27

Tng lai ca IPv6 ......................................................................................................... 27

Ti liu tham kho v IPv6 .................................................................................................. 28

Cc ng link hu ch v IPv4 & IPv6 .......................................................................... 28

Gii thiu IPv6 IPv6 l phin bn mi nht ca Giao thc Internet (IP) v phin bn u tin ca giao thc ny

c trin khai rng ri. IPv6 c pht trin bi IETF gii quyt vn c d bo trc

ca vic suy kit kho a ch IPv4. Phn hng dn ny s gip bn hiu v IPv6 v cc thut ng

lin quan n n cng vi cc v d tham kho thch hp.

Lot bi hng dn ca chng ti da trn ngun ti liu ca: Tutorialspoint

i vi c gi Phn hng dn c thit k gip cho ngi mi hc hiu cc khi nim c bn v IPv6

c yu cu trong khi lm vic vi cc giao thc da trn TCP/IP. Sau khi hon thnh phn hc

ny, bn s thy mnh mc trung bnh, t c s bn c th nng cao trnh ca mnh

ln.



iu kin tin Trc khi bt u tin hnh hc tp vi phn hng dn ny, chng ti gi s rng bn c

nhng hiu bit v cc khi nim c bn v my tnh v mng nh giao thc l g, ti sao chng ta

cn giao thc, cc tng mng.

Tng quan v IPv6 IPv6 l mt giao thc ghi a ch mi c thit k p ng tt c cc yu cu c th c v

internet trong tng lai m c chng ta bit n nh l Internet phin bn 2. Giao thc ny nh

giao thc IPv4 trc, lm vic trn Tng mng (Tng-3). Song song vi vic cung cp mt s

lng to ln v khng gian a ch logic, giao thc ny c nhiu tnh nng phong ph m t gii

quyt nhng nhc im ca IPv4.

Ti sao phi c phin bn IP mi? Cho n ny, IPv4 chng minh n l giao thc ghi a ch nh tuyn mnh m v phc v

chng ta trong nhiu thp k trn k thut phn phi vi n lc tt a. N c thit k vo u

nhng nm 80 v khng nhn c bt k s thay i ln no sau . Ti thi im ra i ca n,

Internet c gii hn ch cho mt s trng i hc cho mc ch nghin cu v ti cc phng

ban ca B quc phng. IPv4 l 32 bit di v cung cp khong 4,294,967,296 (232) a ch. Khng

gian a ch ny c coi l qu ti thi gian . Di y l nhng im chnh m ng vai tr

quan trng cho s ra i ca IPv6:

Internet pht trin theo cp s nhn v khng gian a ch c cho php bi IPv4 ang

bo ha. C mt yu cu c mt giao thc m c th tha mn cc nhu cu v a ch

Internet m tng bt ng trong tng lai.

IPv4 t n khng cung cp bt k tnh nng bo mt no. D liu c m ha vi mt s

ng dng bo mt trc khi c gi trn Internet.

Quyn u tin d liu trong IPv4 khng c cp nht. Mc d IPv4 c mt s bit c

dnh ring cho Kiu dch v hoc Cht lng dch v, nhng chng khng cung cp nhiu

chc nng.

IPv4 cho cc khch hng kh nng c th t nh cu hnh bng tay hoc h c th cn mt

s k thut nh cu hnh a ch. No khng c mt k thut nh cu hnh mt thit b

c a ch IP duy nht trn ton cu.



Ti sao khng phi l IPv5? Ti nay, IP mi ch c cng nhn ch c IPv4. Phin bn t 0 ti 3 c s dng trong khi chnh

giao thc ang trong tin trnh pht trin v th nghim. V th, chng ta c th gi s rt nhiu

cc hot ng nn tng vn tn ti trc khi t mt giao thc vo trong qu trnh sn xut. Tng

t nh th, giao thc phin bn 5 c s dng trong khi th nghim vi giao thc lung d liu

cho Internet. Chng ta c bit v n nh l Giao thc lung d liu (SP) m s dng IP phin

bn 5 gi gn d liu ca n. N khng bao gi c a vo s dng cng cng, nhng n

c s dng.

Di y l bng lit k cc phin bn IP v cch chng c s dng.

Lch s ngn gn Sau s pht trin ca IPv4 trong u nhng nm 80, khng gian a ch IPv4 c sn bt u rt

ngn li mt cch nhanh chng khi nhu cu v a ch tng nhanh theo hm m vi internet. Trc

nhn thc v tnh hung c th pht sinh, IETF, vo nm 1994, bt u pht trin mt giao thc

ghi a ch thay th cho IPv4. Tin trnh ca IPv6 c th c theo di theo phng thc RFC

cng b:

1998 RFC 2460 Basic Protocol

2003 RFC 2553 Basic Socket API

2003 RFC 3315 DHCPv6

2004 RFC 3775 Mobile IPv6

2004 RFC 3697 Flow Label Specification



2006 RFC 4291 Address architecture (revision)

2006 RFC 4294 Node requirement

Vo thng 6/2012, mt s t chc Internet ln chn t Server ca h trn IPv6. Hin ti chng ta

ang s dng k tut Dual Stack thc hin IPv6 song song vi IPv4.

c im ca IPv6 gi nhng tnh nng c bn ca vic ghi a ch IP, IPv6 c thit k li ton b. N cung

cp nhng c im sau:

Khng gian b nh rng hn

Tri ngc vi IPv4, IPv6 s dng s bit nhiu hn 4 ln nh v mt thit b trn

Internet. Vic s dng nhiu bit thm ny c th cung cp gn 3.4x1038 cc kt ni ca

cc a ch khc nhau. Lng a ch ny c th p ng cc nhu cu v vic cp pht a

ch ca hu ht mi th trn th gii ny. Theo tnh ton, mi mt vung trn tri t c th

c cp pht 1564 a ch.

Header c n gin ha

Cc Header ca IPv6 c n gin ha bi vic g b tt c cc thng tin v cc la

chn (m c trong IPv4) khng cn thit ti phn cui ca IPv6. Header ca IPv6 ch ln

hn gp 2 ln so vi trong IPv4 trong khi lng a ch IPv6 l gp 4 ln.

Kiu lin kt end-to-end

Mi h thng by gi c a ch IP duy nht v c th i qua Internet m khng s dng

NAT hoc cc thnh phn phin dch khc. Sau khi IPv6 c ci t v chy trn ton h

thng, mi host c th trc tip kt ni vi host khc trn internet, vi mt s gii hn lin

quan nh Tng la, cc Chnh sch ca t chc.

T ng nh cu hnh

IPv6 h tr c hai ch t ng nh cu hnh Stateful v Stateless ca cc thit b host.

Theo cch ny, s vng mt ca mt DHCP server khng t mt trm dng trn s giao

tip lin on.

nh tuyn/Chuyn tip nhanh hn



Header c n gin ha t tt c cc thng tin khng cn thit ti phn cui ca

Header. Thng tin c cha trong phn u ca Header l thch hp cho mt router to

cc quyt nh nh tuyn, v th vic to cc quyt nh nh tuyn s nhanh nh vic kim

tra phn lnh Header.

IPSec

Ngay t u, n c quyt nh rng IPv6 phi c bo mt IPSec, lm cho n an ton

hn IPv4. c im ny by gi c to ty .

Khng Broadcast

Mc d Ethernet/Token Ring c cho l mng Broadcast bi v chng h tr truyn ti

Broadcast, IPv6 khng c h tr Broadcast no na. N s dng Multicast giao tip vi

nhiu host.

H tr Anycast

y l c trng khc ca IPv6. IPv6 gii thiu ch Anycast trong vic nh tuyn gi

d liu. Trong ch ny, nhiu giao thc thng qua internet c ch nh cng a ch

Anycast IP. Cc router, trong khi nh tuyn, gi gi d liu ti ch n gn nht.

Tnh lu ng

IPv6 khi c thit k vn gi gn tnh lu ng. c im ny cho cc host (nh mobile

phone) kh nng di ng xung quanh cc khu vc a l khc nhau v vn gi c kt ni

vi cng a ch IP. Tnh lu ng ny ca IPv6 li dng kh nng t ng nh cu hnh IP

v cc Extension Header.

H tr quyn u tin c nng cao

IPv4 s dng 6 bit DHCP v 2 bit ECN cung cp Cht lng dch v (Quality of Service)

nhng n ch c th c s dng nu cc thit b end-to-end h tr n, l, thit b

ngun v ch n nm di mng phi h tr n.

Trong IPv6, hng Truyn ti v nhn hiu Dng d liu (Traffic class and Flow label) c

s dng ch cho cc router nm di cch x l mt cch hiu qu gi d liu v nh

tuyn n.

S chuyn tip mt m



Khng gian a ch IP ln trong IPv6 cho kh nng cp pht cc thit b vi cc a ch IP

duy nht trn ton cu. K thut ny lu gi cc a ch IP v NAT khng cn yu cu. V

th cc thit b c th gi/nhn d liu vi nhau, v d, VoIP v/hoc bt k phng tin

lung d liu no c th c s dng mt cch hiu qu hn.

Mt s tht khc l, Header c trng ti t hn, v th cc router c th to cc quyt nh

chuyn tip v chuyn chng ti ch khc nhanh nh khi chng n.

Tnh c th m rng

Mt trong nhng li th ln nht ca IPv6 Header l n c th m rng nhp thm

thng tin trong phn ty chn. IPv4 cung cp ch 40 byte cho phn ty chn, trong khi

ty chn trong IPv6 c th nhiu nh kch c ca chnh gi IPv6.

Cc ch nh v trong IPv6 Trong ch nh v v lin kt mng my tnh lin quan ti k thut hosting mt a ch trn mng.

IPv6 cung cp mt s kiu ch m bi n mt host n c th c nh v. Nhiu hn mt host

c th c nh v cng mt lc hoc host ti khong cch gn nht c th c nh v.

Ch nh v Unicast trong IPv6 Trong ch nh v Unicast, mt giao thc IPv6 c xc nh mt cch duy nht trong mt on

mng. Gi IPv6 cha c a ch ngun v ch n. Mt giao thc host c trang b vi mt a

ch IP m l duy nht trong on mng . Khi mt mng chuyn mch hoc mt router nhn mt

gi Unicast, c hng ch ti mt host n, n gi ra cho mt trong nhng giao din u ra

ca n m kt ni ti host c th .



Ch nh v Multicast trong IPv6 Ch Multicast trong IPv6 l ging nh trong Ipv4. Gi d liu hng ch ti nhiu host c

gi trn mt a ch Multicast c bit. Tt c cc host c lin quan trong thng tin Multicast, cn

tham gia nhm Multicast u tin. Tt c cc giao thc m tham gia nhm nhn gi ny v x l

n, trong khi cc host khc khng c lin quan b qua thng tin ny.

Ch nh v Anycast trong IPv6 IPv6 gii thiu mt kiu nh v mi, m c gi l nh v Anycast. Trong ch nh v ny,

nhiu giao thc c ch nh cng mt a ch Anycast IP. Khi mt host mun giao tip vi mt



host c trang b vi mt a ch Anycast IP, n gi mt thng bo Unicast. Vi s gip ca k

thut nh tuyn phc tp, m thng bo Unicast c phn phi ti host gn nht vi trm gi.

By gi chng ta xem mt v d v Server tutorialpoints.com, c t ti tt c cc lc a. Gi s

rng tt c cc Server c ch nh mt a ch Anycast IP n (IPv6). By gi khi mt ngi s

dng t Chu u mun truy cp vo trang ny, DNS ch ti server m t chnh Chu u. Nu mt

ngi s dng t n mun truy cp vo trang, DNS sau s ch ti web t ti Asia. Cc

quan h n nht c s dng trong Chi ph nh Tuyn (Routing Cost).

Trong hnh trn, khi mt client c gng tip cn mt server, yu cu c chuyn tip ti server

vi Chi ph nh tuyn thp nht.

Kiu & nh dng a ch trong IPv6 H thng s thp lc phn trong IPv6 Trc khi gii thiu nh dng a ch IPv6, chng ta s xem qua H thng s thp lc phn. Thp

lc phn l mt h thng s v tr m s dng c s 16. biu din cc gi tr trong nh dng c

c, h thng ny s dng cc k t t 0-9 biu th gi tr t 0-9 v A-F biu th cc gi tr

t 10-15. Mi k s trong H thp lc phn c th biu din gi tr t 0-15.



[Bng chuyn i]

Cu trc a ch trong IPv6 Mt a ch IPv6 c to bi 128 bit c phn chia thnh 8 khi 16 bit. Mi khi sau c

chuyn i thnh 4 k s thp lc phn c phn bit nhau bi du chm.

V d di y l mt a ch IPv6 128 bit c biu din trong nh dng nh phn v c phn

chia thnh 8 khi 16 bit:

0010000000000001 0000000000000000 0011001000111000 1101111111100001

0000000001100011 0000000000000000 0000000000000000 1111111011111011

Mi khi sau c chuyn i thnh H thp lc phn v phn bit nhau bi du hai chm (:).

2001:0000:3238:DFE1:0063:0000:0000:FEFB

Ngay sau khi chuyn i vo nh dng Thp lc phn, a ch IPv6 vn cn di. IPv6 cung cp mt

vi quy tc rt ngn a ch ny. Cc quy tc nh sau:

Quy tc 1: Loi b s 0 dn u:

Trong khi 5 (0063), hai s 0 dn u c th b b qua:

2001:0000:3238:DFE1:63:0000:0000:FEFB



Quy tc 2: Nu hai hoc nhiu khi lin tc cha cc s 0 lin tc, b qua tt c chng v thay i

bng hai du hai chm(::):

2001:0000:3238:DFE1:63::FEFB

Khi c cc s 0 lin tc c th c thay bng ch mt s 0 bi ::, v th nu vn c mt khi m

c cc s 0 lin tc trong a ch, chng ta c th ch dng mt s 0, nh khi 2:

2001:0:3238:DFE1:63::FEFB

Interface ID trong IPv6 IPv6 c 3 kiu giao thc a ch Unicast khc nhau. Mt na phn phn th hai ca a ch (64 bit

cui) thng c s dng cho Giao din ID. a ch MAC ca mt h thng c to thnh bi

48 bit v c biu din trong H thp lc phn. Cc a ch MAC c cho l c th c ch

nh mt cch duy nht trn ton th gii. Giao thc ID li dng tnh duy nht ny ca cc a ch

MAC. Mt host c th t ng nh hnh Giao thc ID ca n bi s dng nh dng EUI-64

(Extended Unique Identifier) ca IEEE. u tin, mt host phn chia a ch MAC ring ca n vo

trong 2 na 24 bit. Sau , gi tr thp lc phn (16 bit) 0xFFFE c xen vo gia hai na ca a

ch MAC, l kt qu t nh dng EUI-64.

[nh:ID Giao din EUI-64 ]

S chuyn i ca EUI-64 vo trong B nhn din giao thc IPv6

chuyn i EUI-64 vo trong B nhn din giao thc IPv6, bit th 7 c ngha nht ca EUI-64

c b.



[nh: IP Giao din IPV6]

a ch Unicast ton cu trong IPv6 Kiu a ch ny tng ng vi a ch cng cng trong IPv4. Cc a ch Unicast ton cu trong

IPv6 c th nhn din v nh v duy nht trn ton cu.

[nh: a ch Unicast

ton cu]

Tin t nh tuyn ton cu (Global Routing Prefix): 48 bit quan trng nht c ch nh nh l

Tin t nh tuyn ton cu m c ch nh ti h thng t qun l ring bit. 3 bit quan trng

nht ca GRP thng c thit lp l 001.

a ch Lin kt-Ni b (Link-Local) trong IPv6 a ch IPv6 t ng nh cu hnh c bit n nh l a ch Lin kt-Ni b. a ch ny

thng bt u vi FE80. 16 bit u tin ca a ch Lin kt-Ni b thng c thit lp l 1111

1110 1000 0000 (FE80). 48 bit tip theo thng c thit lp l 0, v th:

[nh:

a ch Lin kt-Ni b]



Cc a ch Lin kt-Ni b c s dng giao tip trong cc host IPv6 ch trn mt lin kt

(on Broadcast). Nhng a ch ny khng th nh tuyn, v th mt Router khng bao gi

chuyn tip nhng a ch ny ra bn ngoi ng lin kt.

a ch Duy nht-Ni b (Unique-Local) trong IPv6 Kiu a ch IPv6 ny l duy nht trn ton cu, nhng n nn c s dng trong giao tip ni b.

Phn na th hai ca a ch ny cha Giao din ID v phn na u c phn chia thnh

Prefix, Local Bit, Global ID v Subnet ID.

[nh:

a ch Duy nht-Ni b]

Prefix (tin t) thng c thit lp l 1111 1110. Local Bit (bit ni b) thit lp l 1 nu a ch

c ch nh ni b. Cho n nay, ngha ca vic thit lp Local bit v 0 cha c nh ngha.

V th, Unique Local thng bt u vi FD.

Phm vi ca cc a ch Unicast trong IPv6

[nh: Phm vi ca cc

a ch Unicast]



Phm vi ca a ch Link-Local c gii hn trong on mng. a ch Unique Local l ton cu,

nhng khng c nh tuyn qua internet, gii hn phm vi ca chng ti gii hn ca mt t

chc. a ch Global Unicast l duy nht trn ton cu v c th nhn bit.

Cc a ch c bit trong IPv6 Phin bn 6 c cu trc a ch IP hi phc tp hn trong IPv4. IPv6 dnh ring mt s a ch

v ghi ch a ch cho nhng mc ch c bit. Bn hy quan st bng bn di.

Nh ch trong bng, a ch 0:0:0:0:0:0:0:0/128 khng xc nh bt c ci g v c cho

l mt a ch khng c xc nh. Sau khi n gin ha, tt c cc s 0 c rt gn v

::/128.

Trong IPv4, a ch 0.0.0.0 vi netmask 0.0.0.0 biu din tuyn mc nh. Khi nim tng

t c p dng cho IPv6, a ch 0:0:0:0:0:0:0:0 netmask tt c s 0 biu din tuyn mc

nh. Sau khi p dng quy tc IPv6, a ch ny c rt gn thnh ::/0.

Cc a ch loopback trong IPv4 c biu din bi dy 127.0.0.1 ti 127.255.255.255.

Nhng trong IPv6, ch 0:0:0:0:0:0:0:1/128 biu din a ch Loopback. Sau khi loopback a

ch, n c th c biu din nh ::1/128.

a ch Multicast dnh ring cho cc Giao thc nh tuyn

Bng trn ch cc a ch Multicast dnh ring c s dng bi giao thc nh tuyn ni

b.

Cc a ch ny c dnh ring theo quy tc tng t nh trong IPv4.



a ch Multicast dnh ring cho cc Router/Node

Nhng a ch ny gip cc router v host giao tip vi cc router v host c sn trn mt

on mng m khng c nh cu hnh vi mt a ch IPv6. Cc host s dng EUI-64

xy dng trn c s t ng nh cu hnh t nh hnh mt a ch IPv6 v sau giao

tip vi cc host/router trn on mng bi phng thc ca cc a ch ny.

Cc trng Header trong IPv6 iu k diu ca IPv6 nm trong Header ca n. Mt a ch IPv6 bng 4 ln a ch IPv4, nhng

iu ng ngc nhin l, Header ca IPv6 ch ln hn 2 ln so vi Header trong IPv4. Cc Header

trong IPv6 c mt Fixed Header (Header c nh) v 0 hoc nhiu hn cc Header ty (Optical

Header). Tt c thng tin cn thit m thit yu cho mt router c gi trong Header c nh.

Header ty cha cc thng tin khng bt buc m gip cc router hiu cch x l mt gi/dng

d liu.

Header c nh (Fixed Header) trong IPv6

[nh: IPv6

Fixed Header]

Header c nh l 40 byte di v cha cc thng tin sau:



STT Trng & Miu t

1 Version - Phin bn (4 bit): N biu din phin bn ca Giao thc

Internet, v d: 0110.

2 Traffic Class - Hng truyn ti (8 bit): 8 bit ny c phn chia thnh 2

phn. 6 bit quan trng nht c s dng cho Kiu dch v ch dn

Router bit nhng dch v g nn c cung cp ti gi d liu ny. 2 bit t

quan trng hn c s dng cho ECN.

3 Flow Label - Nhn dng (20 bit): Nhn ny c s dng duy tr dng

lin tc ca gi d liu thuc s hu ca mt giao tip. Cc ngun dn

nhn lin lc gip router xc nhn rng mt gi d liu c th thuc s

hu ca mt dng thng tin ring bit. Trng ny gip trnh vic xp xp

li cc gi d liu. N c thit k cho phng tin lung/thi gian thc.

4 Payload Length - di trng ti (16 bit): Trng ny c s dng

chi cho cc router bit rng bao nhiu thng tin v mt gi c th cha

trong trng ti ca n. Trng ti gm cc Header ty v d liu Tng trn

(Upper Layer). Vi 16 bit, ln ti 65535 byte c th c biu th; nhng

nu cc trng Header ty cha Hop-by-Hop Extension Header, th sau

, trng ti c th vt qu 65535 byte v trng ny c thit lp v 0.

5 Next Header (8 bit): Trng ny c s dng ch hoc kiu ca

Extension Header hoc nu Extension Header khng hin th th khi n

ch Upper Layer PDU. Cc gi tr ca kiu Upper Layer PDU l ging nh

trong IPv4.

6 Hop Limit - Gii hn Hop (8 bit): Trng ny c s dng dng gi

d liu lp v hn trong mng. N ging nh TTL trong IPv4. Gi tr

ca trng Hop Limit c gim bt i 1 khi n truyn qua mt link (mt

router/hop). Khi trng ny tin v 0, gi c loi b.



7 Source Address - a ch ngun (128 bit): Trng ny ch a ch ca

ngun ca gi d liu.

8 Destination Address - a ch ch n (128 bit): Trng ny cung cp

a ch ch n.

Extension Header trong IPv6 Trong IPv6, Fixed Header ch cha nhng thng tin m cn thit, trnh vic nhng thng tin

hoc khng c yu cu hoc him khi c s dng. Tt c nhng thng tin ny c t gia

trng Fixed Header v Upper Layer Header, trong Extension Header. Mi Extension Header

c nhn din bi mt gi tr ring bit.

Khi cc Extension Header c s dng, trng Next Header ca Fixed Header trong IPv6 ch ti

trng Extension Header u tin. Nu c nhiu hn mt Extension Header, th khi trng Next

Header ca Extension Header u tin ch ti trng Extension Header th hai, v tng t nh

th. Trng Next Header ca Extension Header cui cng ch ti Upper Layer Header. V th, tt

c cc Header ch ti Header k tip trong mt phng thc danh sch kt ni.

Nu trng Next Header cha gi tr 59, n ch dn rng khng c Header no sau trng ny, k

c Upper Layer Header.

Extension Header tip theo phi c h tr bi mi RFC 2460:

Dy lin tc ca Extension Header s l:



Nhng Header ny:

1. c x l bi cc ch n u tin v tip theo .

2. c x l bi ch n Cui cng.

Cc Extension Header c xp xp theo th t ci ny sau ci kia trong mt phng thc danh

sch lin kt, nh c miu t trong s di:

[nh:

nh dng kt ni Extension Header]

Giao tip trong IPv6 Trong IPv4, mt host m mun giao tip vi host khc trn mng cn c mt a ch IP bi hoc

phng thc DHCP hoc bi s t nh cu hnh. Ngay sau khi mt host c trang b vi mt s

a ch IP c hiu lc, n c th giao tip vi bt k host no trn Subnet. truyn tin trn Tng-

3, mt cng host phi bit a ch IP ca host khc. Truyn tin trn mt link, c thit lp bi

phng thc phn cng c nhng bi cc a ch MAC. bit a ch MAC ca mt host m

a ch IP ca n c bit, mt host gi ARP Broadcast v trong s phn hi, host d nh gi

tr li a ch MAC ca n.

Trong IPv6, khng c cc k thut Broadcast. N khng l mt s cn thit cho mt IPv6 cho host

kh nng t c mt a ch IP t DHCP hoc t cch t nh cu hnh, nhng n c th t

ng nh cu hnh IP ca ring n.

ARP c thay i bi ICMPv6 Neighbor Discovery Protocol.



Giao thc pht hin ln cn (Neighbor Discovery Protocol) trong IPv6 Mt host trong mng IPv6 c kh nng t ng nh hnh chnh n vi mt a ch Lin kt-Ni b

duy nht. Ngay sau khi host nhn c mt a ch IPv6, n tham gia mt s nhm Unicast. Tt c

s truyn tin lin quan ti on mng din ra ch trn nhng a ch Unicast . Mt host i qua

dy cc tuyn b ca IPv6:

Neighbor Solicitation: Sau khi nh cu hnh IPv6 tt c bng tay hoc bng DHCP hoc

bi s t ng nh cu hnh, host gi mt thng bo Neighbor Solicitation ra ngoi ti a

ch Multicast FF2::1/16 cho tt c cc a ch IPv6 ca n bit rng khng ai khc c th

cng chim c cc a ch ny.

DAD (Duplicate Address Detection): Khi host khng nghe bt c nhng g v on mng

lin quan ti thng bo Neighbor Solicitation ca n, n gi s rng khng c bn sao a

ch no tn ti trn on mng.

Neighbor Advertisement: Sau khi ch nh cc a ch ti cc giao din ca n v lm

chng chy, host ln na gi ra ngoi mt thng bo Neighbor Advertisement ni cho tt

c cc host khc trn on mng, m n ch nh cc a ch IPv6 ti cc giao thc

ny.

Mt khi mt host thc hin vic nh cu hnh ca cc a ch IPv6 ca n, n thc hin cc th

sau tip theo:

Router Solicitation: Mt host gi mt thng bo Router Solicitation dng Unicast

(FF02::2/16) ra ngoi on mng ca n bit s hin din ca bt k router no trn

on mng ny. N gip host nh cu hnh router nh l gateway mc nh ca n. Nu

gateway mc nh ny go down, host c th chuyn ti router mi v lm cho router ny

tr thnh gateway ca n.

Router Advertisement: Khi mt host nhn c mt thng bo Router Solicitation, n

phn hi tr li ti host, qung b s hin din ca n trn link .

Redirect: N c th l tnh hung ti ni mt Router nhn mt yu cu Router Solicitation

nhng n bit rng khng phi l gateway tt nht cho host. Trong tnh hung ny,

router gi tr li mt thng bo Redirect ni cho host rng c sn mt router next-hop tt



hn. Next-hop l ni m host s gi d liu c hng ch ca n ti mt host m

khng thuc v cng on mng.

Subnetting trong IPv6 Trong IPv4, cc a ch c to trong cc hng. Cc a ch IPv4 phn hng xc nh r rng cc

bit c s dng cho cc tin t mng v cc bit c s dng cho cc host trn mng. chia

Subnet (Subnetting) trong IPv4, chng ta s dng netmask phn hng mc nh cho php chng ta

mn cc bit ca host s dng nh cc bit ca Subnet. iu ny to ra kt qu l nhiu Subnet

nhng t host mi Subnet hn. l, khi chng ta mn cc host bit to mt subnet, n lm

cho chng ta c t bit hn c s dng cho cc a ch host.

Cc a ch IPv6 s dng 128 bit biu din mt a ch m bao gm cc bit c s dng cho

vic Subnetting. Na th hai ca a ch (64 bit t quan trng hn) thng ch c s dng cho

cc host. V th, khng c s dung ha no nu chng ta chia Subnet cho mng.

[nh: Subnetting trong IPv6]

16 bit ca Subnet l tng ng vi mng Hng B trong IPv4. S dng cc bit Subnet ny, mt

t chc c th c 65 nghn Subnet khc m l qu so vi nhu cu.

V th cc tin t nh tuyn l /64 v host l 64 bit. Chng ta c th chia nhiu Subnet hn (thay v

16 bit) bi vic mn cc host bit. Nhng n c ngh rng 64 bit lun lun l c s dng

cho cc a ch host bi v vic t ng nh cu hnh yu cu 64 bit.

Chia Subnet trong IPv6 lm vic trn khi nim ging nh l Variable Length Subnet Masking trong

IPv4.

Tin t /48 c th c cp pht cho mt t chc cung cp n li ch ca vic c tin t Subnet

/64, m c 65535 Subnet, mi Subnet c 264 host. Mt tin t /64 c th c ch nh ti mt kt

ni point-to-point ni m ch c 2 host (hoc thit b IPv6) trn mt link.

Chuyn tip t IPv4 ti IPv6 S chuyn tip hon ton t IPv4 sang IPv6 vn cha th xy ra bi v IPv6 cha th tng thch

ngc. Kt qu l mt tnh hung m hoc mt site trn IPv6 hoc n khng. N l khng ging



nh s thc hin cc cng ngh mi khc m mt cng ngh mi hn l tng thch ngc h

thng c hn c th vn lm vic vi phin bn mi m khng cn thm bt c s thay i no.

gii quyt s hn ch ny, chng ta c mt s cng ngh m c th c s dng bo m

s chuyn tip tuy chm nhng nhp nhng t IPv4 sang IPv6.

Dual Stack Routers Mt router c th c ci t vi c cc a ch IPv4 v IPv6 c nh hnh trn cc giao thc

ca n ch ti gin IP mng thch hp.

[nh: Dual

Stack Router]

Trong s trn, mt server c a ch IPv4 cng nh a ch IPv6 c nh hnh cho n c

th giao tip vi tt c cc host trn c hai mng IPv4 v IPv6 vi s gip ca Dual Stack

Router. Dual Stack Router c th giao tip vi c hai mng. N cung cp mt trung gian cho cc

host truy cp mt server m khng phi thay i phin bn IP tng ng.

Tunneling Trong mt bi cnh m cc phin bn IP khc nhau tn ti trn ng truyn trung gian hoc

mng truyn ti, tunneling cung cp mt gii php tt hn d liu ca ngi s dng c th

truyn qua mt phin bn IP khng c h tr.



[nh:

Tunneling]

Gin trn miu t cch hai mng IPv4 t xa c th truyn tin thng qua mt Tunnel, ni m

mng truyn ti trn IPv6. Tin trnh ngc li l cng c th ni m mng truyn ti trn IPv6 v

cc site t xa c nh truyn tin l trn IPv4.

NAT Protocol Translation y l phng thc quan trng khc trong truyn ti ti IPv6 bi phng thc ca mt thit b

c cho quyn NAT-PT (Network Address Translation Protocol Translation). Vi s gip ca

mt thit b NAT-PT, vic truyn tin thc s c th din ra gia cc gi d liu IPv4 v IPv6 v

ngc li. Bn theo di gin di:

[nh: NAT -

Protocol Translation]

Mt host vi a ch IPv4 gi mt yu cu ti mt server c cho kh nng vi a ch IPv6 trn

Internet m khng hiu a ch IPv4. Trong trng hp ny, thit b NAT-PT c th gip chng giao

tip vi nhau. Khi host ca IPv4 gi mt gi yu cu ti IPv6 server, thit b/router NAT-PT tho ri

gi IPv4, g b Header ca n, v thm vo Header ca IPv6 v truyn n thng qua Internet. Khi

mt phn hi t IPv6 n host ca IPv4, router thc hin cng vic ngc li.

Kh nng lu ng ca IPv6 Khi mt host c kt ni ti mt link hoc mng, n thu c mt a ch IP v tt c giao tip

din ra s dng a ch IP trn lin kt . Ngay sau khi, host ging nh vy thay i v tr vt l



ca n, m l, di chuyn vo trong area / subnet / network / link khc, a ch IP ca n thay i

tng ng, v tt c giao tip din ra trn host s dng a ch IP c.

Kh nng lu ng (Mobility) ca IPv6 cung cp mt k thut cho host i lang thang (roam around)

quanh cc link khc nhau m khng tht lc bt c s kt ni/truyn tin v a ch IP ca n.

Cc i tng c lin quan trong cng ngh ny l:

Mobile Node: Thit b m cn kh nng lu ng ca IPv6.

Home Link: Lin kt ny c nh cu hnh vi tin t home subnet v y l ni m thit

b Mobile IPv6 nhn a ch Home ca n.

Home Address: y l a ch m Mobile Node ly c t Home Link. y l a ch c

nh ca Mobile Node. Nu Mobile Node vn cn trong cng Home Link, truyn tin gia cc

i tng khc nhau din ra nh bnh thng.

Home Agent: y l mt router m ng vai tr nh mt th ghi cho Mobile Node. Home

agent c kt ni ti Home Link v duy tr thng tin v tt c cc Mobile Node, Home

Address ca n, v a ch IP hin ti ca n.

Foreign Link: Bt c Link khc m khng c Home Link ca Mobile Node.

Care-of Address: Khi mt Mobile Node nhn mt nh km ti mt Foreign Link, n ly

c mt a ch IP mi ca Subnet ca Foreign Link . Home Agent duy tr thng tin ca

c Home Address v Care-of Address. Nhiu a ch Care-of c th c ch nh ti mt

Mobile Node, nhng ti bt c trng hp no, ch c mt a ch Care-of c s kt dnh

vi Home Address.

Correspondent Node: Bt k thit b c cho kh nng m d nh giao tip vi Mobile

Node.

Qu trnh hot ng ca Mobility ca IPv6 Khi mt Mobile Node trong Home Link ca n, tt c giao tip din ra trn a ch Home nh hnh

di:



[nh:

Mobile Node c kt ni ti Home Link]

Khi mt Mobile Node ri khi Home Link ca n v c lin kt ti mt vi Foreign Link, c im

lu ng ca IPv6 thc hin vai tr ca n. Sau khi nhn kt ni ti mt Foreign Link, Mobile Node

ly c mt a ch IPv6 t Foreign Link. a ch ny c gi l a ch Care-of. Mobile node gi

mt yu cu kt dnh ti Home Agent vi a ch Care-of mi. Home Agent kt dnh a ch Home

ca Mobile Node vi a ch Care-of, thit lp mt Tunnel gia hai thit b.

Bt c khi no mt Corresponden Node c gng thit lp kt ni vi Mobile Node (trn a ch

Home ca n), Home Agent chn gi d liu v chuyn n ti Care-of Address ca Mobile Node

qua Tunnel m c thit lp.

[nh:

Mobile Node c kt ni ti Foreign Link]



S ti u ha tuyn ca IPv6 Khi mt Correspondent Node khi to mt giao tip bi gi cc gi ti Mobile Node trn Home

Address, cc gi ca n c tunnel ti Mobile Node bi Home Agent. Trong ch ti u ha

nh tuyn, khi Mobile Node nhn mt gi d liu t Correspondent Node, n khng chuyn s

phn hi ti Home Agent. Thay vo , n gi gi ny trc tip ti Correspondent Node bi s

dng a ch Home nh l a ch ngun. Ch nu l ty v khng c s dng theo mc

nh.

nh tuyn (Routing) trong IPv6 Khi nim nh tuyn tn ti nh trong trng hp IPv6 nhng hu ht tt c cc giao thc nh

tuyn c xc nh li tng ng. Chng ta bn lun trc , cch mt host giao tip ti

gateway ca n. nh tuyn l mt tin trnh chuyn d liu c th nh tuyn bi chn tuyn tt

nht trong mt s tuyn hoc ng truyn c sn ti ch n. Mt Router l mt thit b m

chuyn tip d liu m khng c hng ch mt cch r rng ti n.

Tn ti hai mu giao thc nh tuyn:

Distance Vector Routing Protocol Giao thc nh tuyn vecto khong cch: Mt

router ang chy trn giao thc ny qung b cc tuyn c kt ni ca n v bit v cc

tuyn mi t router hng xm ca n. Chi ph nh tuyn tin ti ch n c tnh

ton bi phng thc cc hop gia ngun v ch n. Mt router tin cy vo cc router

hng xm ca n cho vic chn ng truyn tt nht, m cng c bit nh l nh

tuyn bi tin n. RIP v BGP l cc Giao thc vecto khong cch.

Link-State routing protocol Giao thc nh tuyn Trng thi-Lin kt: Giao thc ny

nhn trng thi ca lin kt v qung b ti cc router hng xm ca n. Thng tin v lin

kt mi c bit t cc router ngang bc. Sau khi tt c thng tin nh tuyn c

ng quy, Giao thc ny s dng thut ton ring ca n tnh ton ng truyn tt

nht trong tt c cc lin kt c sn. OSPF v IS-IS l cc giao thc nh tuyn trng thi

lin kt v c hai giao thc ny u s dng thut ton ng truyn u tin ngn nht

(Shortest Path First) ca Djikstra.

Cc giao thc nh tuyn c th c phn chia thnh hai loi:



Giao thc nh tuyn ni vi (Interior Routing Protocol): Cc giao thc trong loi ny

c s dng trong mt h thng hoc t chc t qun l phn phi cc tuyn gia tt

c cc router bn trong gii hn ca n. V d: RIP, OSPF.

Giao thc nh tuyn ngoi vi (Exterior Routing Protocol): Giao thc loi ny phn phi

thng tin nh tuyn gia hai h thng hoc t chc t qun l. V d: BGP.

Cc giao thc nh tuyn trong IPv6 RIPng

RIPng l vit tt ca Routing Information Protocol Next Generation - L giao thc thng tin

nh tuyn th h mi. y l giao thc nh tuyn ni vi v l mt giao thc vecto khong

cch. RIPng c nng cp h tr IPv6.

OSPFv3

OSPFv3 l vit tt ca Open Shortest Path First version 3 - y l M ng truyn ngn

nht u tin phin bn 3, Mt giao thc nh tuyn ni vi m c chnh sa h tr

IPv6. y l mt Giao thc trng thi - lin kt v s dng thut ton ca Djikrata tnh

ton ng truyn tt nht ti tt c ch n.

BGPv4

BGPv4 l vit tt ca Border Gateway Protocol - N ch m Giao thc gateway ngoi vi tiu

chun c sn. BGP l mt giao thc vecto khong cch m nhn H thng t qun l nh

l calculation metric, thay v s cc router nh l Hop. BGPv4 l s nng cp cu BGP

h tr nh tuyn IPv6.

Cc giao thc c thay i h tr IPv6 ICMPv6: L vit tt ca Internet Control Message Protocol version 6 - Giao thc thng bo

iu khin internet phin bn 6 l mt s nng cp ca ICMP thu nhn cc yu cu

IPv6. Giao thc ny c s dng cho cc chc nng thm d, thng bo li v thng tin,

cc mc ch thng k. Giao thc pht hin ln cn (NDP) ca ICMPv6 thay th cho ARP

v gip pht hin cc router ln cn trn ng lin kt.

DHCPv6: L vit tt ca Dynamic Host Configuration Protocol version 6 - Giao thc nh

hnh host ng phin bn 6 l mt s b sung ca DHCP. IPv6 cho cc host kh nng

khng yu cu bt k DHCP server no ly c a ch IP khi chng c th t ng



nh cu hnh. Khng phi chng cn DHCPv6 t DNS server bi v DNS server c th

c thm d v t nh cu hnh thng qua Giao thc pht hin ln cn ICMPv6.

DHCPv6 server c th cha c s dng cung cp nhng thng tin ny.

DNS: Khng c phin bn DNS mi no nhng by gi n c trang b vi phn m rng

cung cp s h tr cho vic truy vn cc a ch IPv6. Mt bn ghi AAAA mi c

thm vo phn hi cc thng bo truy vn IPv6. By gi DNS c th phn hi vi c

phin bn IP (4 v 6) m khng cn bt c s thay i no trong nh dng truy vn.

Tng kt v IPv6 IPv4 t nm 1982, l mt cng ngh lnh o Internet. Vi vic cn kit khng gian a ch

IPv4, IPv6 by gi ang dn kim sot Internet, m c gi nh l Internet 2.

IPv4 c trin khai rng ri v s thay th bi IPv6 s khng l vic d dng. Cho ti nay, IPv6

mi ch xm nhp vo khng gian a ch ca IPv4 cha ti 1%.

Th gii t chc bui l k nim cho mng IPv6 (m c bit nh l Ngy IPv6 Th gii) vo

8/6/2011 vi mc ch th nghim a ch IPv6 qua Internet. Vo ngy 6/6/2012, cng ng

Internet chnh thc khai trng IPv6. Ngy ny, tt c cc ISP ngi m cung cp IPv6 kch

hot n trn min cng cng v gi n hot ng. Tt c cc nh sn xut thit b cng tham

gia ngh chy IPv6 trn cc thit b c thit k ring.

y l mt bc tin c hoan nghnh bi cng ng Internet.

Cc t chc c cung cp nhiu cch khc nhau chuyn tip t IPv4 ti IPv6. Cc t chc

ny cng sn sng th nghim IPv6 trc khi vic chuyn tip hon ton c th chy ng thi c

IPv4 v IPv6. Cc mng ca cc phin bn IP khc nhau c th giao tip v d liu ngi s dng

c th c tunnel truyn qua ti site khc.

Tng lai ca IPv6 Hu ht cc pht trin IPv6 ang c thc hin bin ngoi US v Chu u. n v Trung Quc

ang thc hin cc bc thay i ton b khng gian ti IPv6. Trung Quc tuyn b mt k

hoch pht trin 5 nm mang tn Internet Th h tip theo ca nc ny.

Sau 6/6/2012, tt c cc ISP ln chuyn ti IPv6 v phn cn li vn ang c chuyn.



IPv6 cung cp khng gian a ch rng ln v c thit k m rng cc dch v Internet ngy

nay. Cc tnh nng IPv6 internet 2 c th mang li nhiu iu hn s mong i.

Ti liu tham kho v IPv6 Cc ngun sau cha cc thng tin hu ch v IPv4 & IPv6. Mong bn s dng chng hiu su

hn nhng g chng ti cp trong lot bi ny.

Cc ng link hu ch v IPv4 & IPv6 Tutorialspoint Lot bi hng dn ca chng ti xy dng da trn ngun ny.

Transmission Control Protocol - Mt ti liu y v TCP protocol. (RFC 793)

IP/IPv4 Protocol - Mt ti liu y v Internet Protocol Version 4 (RFC 791)

IP/IPv6 Protocol - Mt ti liu y v Internet Protocol Version 6 (RFC 791)

IANA IPv4 Address Space Registry - S cp pht khng gian a ch ca Internet Protocol

version 4 (IPv4).

IPv6 on Wikipedia - Trang wikipedia v IPv6.

IP-Lookup - Bn s tm thy thng tin v a ch IP hin ti ca bn v bt k a ch IP no

khc. N h tr c a ch IPv4 v IPv6.

IP Version 6 Working Group - IP Version 6 Lm vic nhm (ipv6).

Documents

Tài Liệu IPV6 Tiếng Việt