IAEAAEAIEA
AAAAeAIEA 2
INIIAU FRAME RELAY 4
o?aineyoeey eaae?ia 4
fr e ae?ooaeueiua niaaeeiaiey 4
oiiieiaey naoe fr 5
oi?iao eaae?a fr 7
neaiciay eiiiooaoeey 9
iaoaieci oi?aaeaiey iioieaie 9
eiioeaioeey niaeaniaaiiie nei?inoe ia?aaea/e eioi?iaoeee 10
eioaa?aoeey ?a/e 13
n?aaenoaa caueou io naiaa 15
iaaeinoaoee oaoiieiaee 16
eeth/aaua aeieoiaiou fr 16
IIEIAEAIEA NAOAE FRAME RELAY IA ?UIEA 18
ii/aio fr 18
niiniau iino?iaiey naoe fr 18
iniiaiua oaiaeaioeee ?uiea 19
IAI?OAeIAAIEA E EAIAEU AeEss NAOAE FRAME RELAY 22
iniiaiua e?eoa?ee auai?a iai?oaeiaaiey 22
eaiaeu aeey naoae fr 23
CAEETH*AIEA 25
NIENIE EEOA?AOO?U 26
AAAAeAIEA
IOEUeNE?OTHUEE O?AOEE.
Ana aieueoea e aieueoea iauaiu eeeaio-na?aa?iiai o?aoeea ia?aaeathony ii
aeiaaeueiui naoyi. O?aoee, ii?iaeaeaaiue eeeaio-na?aa?iuie
i?eeiaeaieyie, iaienaiiuie aeey eieaeueii-naoaauo n?aae, eiaao, eae
i?aaeei, /?acau/aeii ia?aaiiia?iue oa?aeoa?: cia/eoaeueiay i?iioneiay
niiniaiinoue o?aaoaony a oa/aiea ei?ioeeo eioa?aaeia a?aiaie. Ia?aaea/a
oaeiai o?aoeea ii auaeaeaiiui eeieyi (TDM-eiiiooaoeey) eee ii naoe n
a?aiaiiui ?acaeaeaieai eaiaeia (X.25-eiiiooaoeey) ia yooaeoeaia,
iineieueeo aieueooth /anoue a?aiaie aeinooiiay aieinoue ?anoiaeoaony
aionooth: a?aiaiiua neiou ?aca?ae?othony aia caaeneiinoe io oiai,
ia?aaeaaony eioi?iaoeey eee iao.
A oi aea a?aiy, ?ino eiiiuethoa?iuo i?eeiaeaiee, o?aaothueo
aunieinei?inoiuo eiiioieeaoeee, ?ani?ino?aiaiea eioaeeaeooaeueiuo IE e
?aai/eo noaioeee, aeinooiiinoue aunieinei?inoiuo eeiee ia?aaea/e n
ieceei eiyooeoeeaioii ioeaie — ana yoi iineoaeeei i?e/eiie nicaeaiey
iiaie oi?iu eiiiooaoeee a oa??eoi?eaeueiuo naoyo.
Iniiaiuie o?aaiaaieyie e oaeie oaoiieiaee yaeythony:
aunieay nei?inoue:
ieceea caaea?aeee;
?acaeaeaiea ii?oia e
?acaeaeaiea iieinu i?iioneaiey ia iniiaa ae?ooaeueiuo eaiaeia.
TDM-eiiiooaoeey eaiaeia iaeaaeaao ia?auie aeaoiy oa?aeoa?enoeeaie.
X.25-eiiiooaoeey iaeaoia — iineaaeieie aeaoiy.
O?aineyoeey eaae?ia, ?ac?aaioaiiay, eae iiaay oi?ia eiiiooaoeee iaeaoia,
eae ooaa?aeaeaaony, iaeaaeaao anaie /aou?ueiy oa?aeoa?enoeeaie. Yoa
iiaay oaoiieiaey iineo iacaaiea FRAME RELAY (FR).
IAAeI IAIAI?EOUeNss.
Iaaei iaiai?eoueny, /oi enoi/ieeii iiaeiaiie eioi?iaoeee aeey iaiy, eae,
ai?i/ai, e aeey iiaeaaeythuaai aieueoeinoaa ae?oaeo aaoi?eoaoiuo eeoe
yaeythony neeueii eiiia?/aneea aeo?iaeu ii naoaaui oaoiieiaeyi, n?aaee
ieo: ‘Naoaaua oaoiieiaee e n?aaenoaa nayce’, ‘LAN’, ‘Naoe (Network
World)’, ‘Naoe e nenoaiu nayce’. Iaeiaei, oio oaeo, /oi ana iie
caaiai?eee ia yoie oaoiieiaee n iaiau/aeiie eioaineaiinoueth e
i?aaeeaaatho iai (ei?ii?aoeaiui naoyi) oaea aioiaua ?aoaiey, yaeyaony
na?ueaciui iniiaaieai aeey iiae?iaiiai aiaeeca.
Neaaeoao oaeaea ioiaoeoue, /oi iiaay oaoiieiaey eiaao neeueioth
eiiia?/aneoth noi?iio, i /ai aiai?eo ana aieaa iiauoathuaany eiee/anoai
iinoaaueeia e iieueciaaoaeae oneoa FR. I/aaeaeii, /oi iaeiieai ia iaeue
iiuo e a iaeanoe na?aena oneoa FR.
EAE OAAss IACAAOUe ?
Oa?iei «Frame Relay» aua ia iaoae onoie/eaiai ?onneiai aiaeiaa. N oi/ee
c?aiey i?eiaaeeaaeiinoe yoiai iaoiaea ei iiiaeanoao niiniaia eiiiooaoeee
(eiiiooaoeey niiauaiee, iaeaoia, eaiaeia) iiaeii auei au eniieueciaaoue
neiaini/aoaiea «eiiiooaoeey eaae?ia». Aianoa n oai ae?oaie aa?eaio —
«o?aineyoeey eaae?ia» — iiae/a?eeaaao iniaaiiinoe a?oeoaeoo?u,
iai?aaeaiiua ia onei?aiea ia?aaioee a oceao.
AeAIIUE ?AOA?AO.
A aeaiiii ?aoa?aoa i?eaaaeaiu: iienaiea aaciauo eiioeaioeee i?ioieiea
FR, oiiieiaey naoae FR, noa?u i?eiaiaiey naoae FR, iniiaiua oaiaeaioeee
?uiea a nayce n FR, iai?oaeiaaiea e eaiaeu aeey iino?iaiey
iieiiooieoeeiiaeueiuo naoae FR. Iaeioi?ua aii?inu eanathony iniaaiiinoae
i?aeoeee iino?iaiey naoae FR a ?innee.
Aaoi? ia i?aoaiaeoao ia iieiia iienaiea oaoie/aneie ?aaeecaoeee naoae
FR, iaeiaei i?aaei?eiyoa iiiuoea aeaoue iiiaiieaiiaia i?aaenoaaeaiea i
oaoiieiaee FR.
INIIAU FRAME RELAY.
O?aineyoeey eaae?ia.
Iaoiaeieiaey «o?aineyoeey eaae?ia» naienoaaiia eiiiooaoeeiiiie
oaoiieiaee, ii?aaeaeythuae eioa?oaen eiiiooaoeee eaae?ia (FRAME RELAY
INTERFACE – FRI) n oeaeueth oeo/oaiey ia?aaioee (nie?auaiey a?aiaie
ioaaoa) e oiaiueoaiey noieiinoe ia?aaea/e ec eieaeueiie naoe a
oa??eoi?eaeueioth e aunieinei?inoiuo niaaeeiaiee iaaeaeo EAN. Oaoiieiaey
FR o?aaoao:
ieiia/iuo ono?ienoa, iniauaiiuo eioaeeaeooaeueiuie i?ioieieaie aunieeo
o?iaiae;
ae?ooaeueiuo, naiaiaeiuo io ioeaie eaiaeia nayce;
i?eeeaaeiuo n?aaenoa, niiniaiuo inouanoaeyoue ?acee/iua ia?aaea/e.
Aeaiiay oaoiieiaey ia oieueei i/aiue iiaeoiaeeo aeey oi?aaeaiey
ioeuene?othueie o?aoeeaie iaaeaeo EAN e iaaeaeo EAN e oa??eoi?eaeueiie
naoueth, ii e aaeaioe?oaony aeey ia?aaea/e oaeiai /oanoaeoaeueiiai e
ia?aaea/a o?aoeea, eae aiein.
FRAME RELAY E AE?OOAEUeIUA NIAAeEIAIEss.
I?ioieie FR eniieuecoao no?oeoo?o eaae?ia ia?aiaiiie aeeeiu e ?aaioaao
oieueei ia ia?o?ooao, i?eaioe?iaaiiuo ia onoaiiaeaiea niaaeeiaiey.
Ae?ooaeueiia niaaeeiaiea — iinoiyiiia eee eiiiooe?oaiia (PVC eee SVC) —
iaiaoiaeeii onoaiiaeoue i?aaeaea, /ai aeaa ocea ia/ioo iaiaieaaoueny
eioi?iaoeeae.
PVC (permanent virtual circuits) — yoi iinoiyiiia niaaeeiaiea iaaeaeo
aeaoiy oceaie, eioi?ia onoaiaaeeaaaony a?o/ioth a i?ioeanna
eiioeao?e?iaaiey naoe. Iieueciaaoaeue niiauaao i?iaaeaea?o FR-oneoa eee
naoaaiio aaeieieno?aoi?o, eaeea oceu aeieaeiu auoue niaaeeiaiu, e ii
onoaiaaeeaaao PVC iaaeaeo yoeie eiia/iuie noaioeeyie.
PVC aeeth/aao a naay eiia/iua noaioeee, n?aaeo ia?aaea/e e ana
eiiiooaoi?u, ?aniieiaeaiiua iaaeaeo eiia/iuie noaioeeyie. Iinea
onoaiiaee PVC aeey iaai ?aca?ae?oaony ii?aaeaeaiiay /anoue iieinu
i?iioneaiey, e aeaoi eiia/iui noaioeeyi ia o?aaoaony onoaiaaeeaaoue eee
na?anuaaoue niaaeeiaiea.
Aeaaiaea?y iaoiaeo noaoenoe/aneiai ioeueoeieaene?iaaiey, ianeieueei PVC
iiaoo ?acaeaeyoue iieinu iaeiiai eaiaea ia?aaea/e.
SVC (switched virtual circuits) onoaiaaeeaaaony ii ia?a iaiaoiaeeiinoe —
anyeee ?ac, eiaaea iaeei ocae iuoaaony ia?aaeaoue aeaiiua ae?oaiio oceo.
SVC onoaiaaeeaaaony aeeiaie/anee, a ia a?o/ioth. Aeey iaai noaiaea?ou
ia?aaea/e neaiaeia ii?aaeaeytho, eae ocae aeieaeai onoaiaaeeaaoue,
iiaeaea?aeeaaoue e na?anuaaoue niaaeeiaiea.
PVC eiatho aeaa i?aeiouanoaa iaae SVC. Naoue, a eioi?ie eniieuecothony
SVC, aeieaeia o?aoeoue a?aiy ia onoaiiaeaiea niaaeeiaiee, a PVC
onoaiaaeeaathony i?aaeaa?eoaeueii, iiyoiio iiaoo iaania/eoue aieaa
aunieoth i?iecaiaeeoaeueiinoue. E?iia oiai, PVC iaania/eaatho eo/oee
eiio?ieue iaae naoueth, oae eae i?iaaeaea? eee naoaaie aaeieieno?aoi?
iiaeao auae?aoue iooue ii eioi?iio aoaeoo ia?aaeaaaoueny eaae?u.
Iaeiaei e SVC eiatho ?yae i?aeiouanoa iaae PVC. Iineieueeo SVC
onoaiaaeeaathony e na?anuaathony eaa/a, /ai PVC, oi naoe, eniieuecothuea
SVC, iiaoo eieoe?iaaoue naoe aac onoaiiaeaiey niaaeeiaiee. Yoa
aiciiaeiinoue ieacuaaaony iieaciie a oii neo/aa, anee iieueciaaoaeue
eniieuecoao i?eeiaeaiea, eioi?ia ia iiaeao ?aaioaoue a naoe n
onoaiiaeaieai niaaeeiaiee. E?iia oiai, SVC eniieuecotho iieino
i?iioneaiey, oieueei oiaaea, eiaaea yoi iaiaoiaeeii, a PVC aeieaeiu
iinoiyiii aa ?aca?ae?iaaoue ia oio neo/ae, anee iia iiiaaeiaeony. SVC
oaeaea o?aaotho iaiueoae aaeieieno?aoeaiie ?aaiou, iineieueeo
onoaiaaeeaathony aaoiiaoe/anee, a ia a?o/ioth. E iaeiiaoe, SVC
iaania/eaatho ioeacionoie/eainoue: eiaaea auoiaeeo ec no?iy eiiiooaoi?,
iaoiaeyueeny ia iooe niaaeeiaiey, ae?oaea eiiiooaoi?u auae?atho
aeueoa?iaoeaiue iooue.
I?aaeiacia/aiea yoeo niaaeeiaiee ninoieo a ?anoe?aiee iaeanoe i?eiaiaiey
FR ia ae?oaea oeiu i?eeiaeaiee, oaeea eae aiein, aeaeai e caueuaiiua
i?eeiaeaiey Internet, iiieii i?i/eo. Iaeiaei a ianoiyuaa a?aiy SVC ia
iieo/eee oe?ieiai ?ani?ino?aiaiey, a neeo neiaeiinoe a ?aaeecaoeee. Eae
neaaenoaea, PVC yaeyaony iaeaieaa ?ani?ino?aiaiiui ?aaeeiii nayce a naoe
FR.
OIIIEIAEss NAOE FRAME RELAY
Niaaeeiaiey FR ooieoeeiie?otho ia eaiaeueiii o?iaia — aoi?ie o?iaaiue
iiaeaee OSI (ni. ?en. 1), eniieuecoy iauoth (public), /anoioth (private)
eee aea?eaeioth (hybrid) n?aaeo ia?aaea/e.
?enoiie 1. I?eia? «Frame Relay»-a?oeoaeoo?u
Naoue FR ninoieo ec ia?aeeth/aoaeae (switches) FR, iauaaeeiaiiuo
oeeo?iaie n?aaeie ia?aaea/e. Eiia/iia iai?oaeiaaiea, e i?eia?o,
ia?o?ooecaoi?u, naycuaathony /a?ac FR naoue a iaeiii eee ianeieueeeo
iai?aaeaieyo. A noaiaea?oiie oa?ieiieiaee, ia?aeeth/aoaee FR
i?eiaaeeaaeao e eeanno ono?ienoa DCE (Data Communications Equipment), a
eiia/iia iai?oaeiaaiea iieueciaaoaey — e eeanno DTE (Data Terminal
Equipment).
DTE iauaaeeiythony ii niaoeeoeeaoeeyi i?ioieiea FR UNI (FR
User-to-Network Interface). Ia?aeeth/aoaeue FR, i?aaenoaaeythuee UNI,
/eoaao aae?ana i?eoiaeyueo eaae?ia e ia?o?ooece?oao a niioaaonoaothuai
iai?aaeaiee.
Oece/anee naoe FR ia?acotho y/aenooth no?oeoo?o eiiiooaoi?ia. Iauay
oiiieiaey naoe i?eaaaeaia ia ?enoiea 2.
I?ioieie FR iiaeao eioaa?e?iaaoueny c iiiaeie i?ioieieaie, oaeeie eae
ATM, X.25, IP, SNA, IPX e.o.ae. .
?enoiie 2. Oiiieiaey naoe Frame Relay
I?eia?u iiaeiaiuo a?oeoaeoo? aoaeoo i?eaaaeaiu iicaea. Iai?eia?, ia ?en.
1 iiaeii iaaethaeaoue eioaa?aoeeth i?ioieieia FR e ATM (a neeo naiae
yooaeoeaiinoe, iaeaieaa ?ani?ino?aiaiiue neo/ae). A aeaiiii neo/aa naoue
ATM i?aaeinoaaeyao ae?ooaeueiue naiaiaeiue io ioeaie eaiae nayce.
FR iicaieyao ia?aaeaaaoue eaae?u ?acia?ii aei 4096 aaeo, a yoiai
aeinoaoi/ii aeey iaeaoia Ethernet e Token Ring, iaeneiaeueiay aeeeia
eioi?uo ninoaaeyao 1500 e 4096 aaeo niioaaonoaaiii. Aeaaiaea?y yoiio FR
ia i?aaeoniao?eaaao iaeeaaeiua ?anoiaeu ia naaiaioaoeeth e nai?eo.
OI?IAO EAAe?A FRAME RELAY
Aeey o?ainii?oe?iaee ii naoe FR, aeaiiua naaiaioe?othony a eaae?u.
Oi?iao eaae?a FR i?eaaaeai ia ?en. 3. Iaeei eee ianeieueei iaeiiaaeoiauo
oeaaia neoaeao aeey ?acaeaeaiey eaae?ia.
Eaae? eiaao ?acee/ioth aeeeio, a caaieiaie eiiiooe?oaiiai eaae?a
niaea?aeeo 10-aeoiaue iiia?, eaeaioeoeeaoi? niaaeeiaiey eaiaea aeaiiuo
(Data Link Connection Identifier — DLCI).
?enoiie 3. Oi?iao eaae?a Frame Relay
I?eaaaeai iacia/aiea iieae caaieiaea eaae?a FR:
DLCI – eaeaioeoeeaoi? niaaeeiaiey;
C/R – iiea i?eeeaaeiiai iacia/aiey, ia eniieuecoaony i?ioieieii FR e
ia?aaeaaony ii naoe i?ic?a/ii;
EA – ii?aaeaeyao 2-o, 3-o eee 4-o aaeoiaia iiea aae?ana;
FECN – eioi?ie?oao ocae iacia/aiey i caoi?a;
BECN – eioi?ie?oao ocae-enoi/iee i caoi?a;
DE – eaeaioeoeoee?oao eaae?u, eioi?ua iiaoo auoue na?ioaiu a neo/aa
caoi?a.
?ieue eaeaioeoeeaoi?a niaaeeiaiey DLCI:
Eaaeaeia niaaeeiaiea PVC eiaao 10-aeoiaue eaeaioeoeeaoi?, aeeth/aaiue a
caaieiaie eaae?a FR, iacuaaaiue DLCI. Yoi /enei i?enaaeaaaony ii?oo ocea
FR. I?e onoaiiaea PVC, niaaeeiaieth iacia/aaony iaeei oieeaeueiue iiia?
DLCI aeey ii?oa-enoi/ieea e ae?oaie aeey ii?oa iacia/aiey (oaeaeaiiiai
ii?oa). DLCI i?enaaeaathony oieueei eiia/iui oi/eai PVC — naoue FR
aaoiiaoe/anee iacia/aao DLCI aioo?aiiei oceai ia?aaea/e.
Oaeei ia?acii noa?a aeaenoaey DLCI ia?aie/eaaaony oieueei eieaeueiui
o/anoeii naoe, /oi iicaieyao naoe iiaeaea?aeeaaoue aieueoia /enei
ae?ooaeueiuo eaiaeia. Aeaaiaea?y yoiio ?aciua ia?o?ooecaoi?u a naoe
iiaoo iiaoi?ii eniieueciaaoue oio aea naiue DLCI; yoi iicaieyao naoe
eniieueciaaoue aieueoaa /enei ae?ooaeueiuo eaiaeia. Oaaeeoeu
ia?ae?anoiuo niaaeeiaiee (Cross-Nonnect Tables), ?ani?ino?aiyaiua
iaaeaeo anaie eiiiooaoi?aie FR a naoe, onoaiaaeeaatho niioaaonoaea
iaaeaeo aoiaeyueie e enoiaeyueie DLCI.
Eniieuecoy DLCI, DCE iai?aaeyao aeaiiua io DTE /a?ac naoue a neaaeothuae
iineaaeiaaoaeueiinoe:
FR DTE eieainoee?oao i?eoaaeoee iaeao eee eaae? a FR-eaae?. DTE caaeaao
ei??aeoiue DLCI-aae?an, eioi?ue aa?aony ec niaoeeaeueiie oaaeeoeu
?aiaeaao (look-up table), a eioi?ie ii?aaeaeaii niioaaonoaea iaaeaeo
eieaeueiui aae?anii iaeaoa e niioaaonoaothuei iiia?ii DLCI.
DCE i?iaa?yao oeaeinoiinoue eaae?a, eniieuecoy eiio?ieueioth
iineaaeiaaoaeueiinoue FCS e a neo/aa iaia?oaeaiey ioeaee na?anuaaao
eaae?.
DCE euao iiia? DLCI a oaaeeoea ia?ae?anoiuo niaaeeiaiee (Cross-Connect
Table) e, a neo/aa anee aeey oeacaiiiai DLCI ia ii?aaeaeaia naycue eaae?
na?anuaaaony.
DCE ioi?aaeyao eaae? e oceo iacia/aiey, /a?ac auoaeeeaaiea eaae?a a
ii?o, niaoeeoeoee?iaaiiue a oaaeeoea ia?ae?anoiuo nnueie.
Yoe oaae i?aaenoaaeytho eioa?an e aoaeoo ?anniio?aiu iiae?iaiaa a
niioaaonoaothueo ?acaeaeao.
NEAICIAss EIIIOOAOeEss
Ii n?aaiaieth ni naiei i?aaeoanoaaiieeii, X.25, FR eiaao cia/eoaeueiua
i?aeiouanoaa a i?iecaiaeeoaeueiinoe. Ai a?aiy ?ac?aaioee X.25
niaaeeiaiey a aeiaaeueiuo naoyo nicaeaaaeenue ii aieueoae /anoe ia
iniiaa iaiaa iaaeaaeiie aiaeiaiaie oaoiieiaee. Iiyoiio, /oiau iaeaou
i?eauaaee e iieo/aoaeth aac ioeaie e ii ii?yaeeo, X.25 o?aaoao io
eaaeaeiai i?iiaaeooi/iiai ocea iaaeaeo ioi?aaeoaeai e iieo/aoaeai
iiaeoaa?aeaeaiey oeaeinoiinoe iaeaoa e eni?aaeaiey ethaie iaia?oaeaiiie
ioeaee. Naycue n i?iiaaeooi/iui o?aiaieai caiaaeeyao ia?aaea/o iaeaoia,
oae eae eaaeaeue ocae i?iaa?yao FCS eaaeaeiai iinooiathuaai iaeaoa e
oieueei caoai ia?aaeaao aai aeaeueoa. Oaeei ia?acii, a naoe n eaiaeaie
ieceiai ea/anoaa aicieeatho ia?aaeaiaioe?iaaiiua iaiinoiyiiua ii
aaee/eia caaea?aeee ia?aaeaaaaiuo aeaiiuo. Iiyoiio iaaiciiaeii
ia?aaeaaaoue ii naoyi X.25 /oanoaeoaeueiue e caaea?aeeai o?aoee
(iai?eia? ioeeo?iaaiioth ?a/ue) n oaeiaeaoai?eoaeueiui ea/anoaii.
N iiyaeaieai aunieiiaaeaaeiuo oeeo?iauo eaiaeia oaeay i?iaa?ea noaea
eceeoiae. Iiyoiio a FR, eniieueciaaiea eioi?iai iiae?acoiaaaao iaee/ea
oeeo?iaie eio?ano?oeoo?u, ia aeeth/aiu ooieoeee iienea e ei??aeoeee
ioeaie. Eiiiooaoi?u FR eniieuecotho oaoiieiaeth neaiciie eiiiooaoeee,
i?e eioi?ie eaaeaeue iaeao iai?aaeyaony ia neaaeothuee o?aiceoiue ocae
n?aco aea ii i?i/oaiee aae?aniie eioi?iaoeee, /oi eneeth/aao
ia?aaiiia?iua caaea?aeee. Anee neo/aaony eaeay-eeai ioeaea, eiiiooaoi?u
FR ioa?aeiauaatho eaae?u. Ooieoeey eni?aaeaiey ioeaie aiceaaaaony ia
iaaeeiioeaaie i?ioieie aieaa aunieiai o?iaiy (iai?eia? TCP eee SPX). I?e
oaeii iiaeoiaea iaeeaaeiua ?anoiaeu ii ia?aaioea a ?an/aoa ia eaae?
nieaeathony, /oi cia/eoaeueii iiauoaao i?iioneioth niiniaiinoue e
aeaeaao aa ?aaeaiaioe?oaiie.
IAOAIECI OI?AAEAIEss IIOIEAIE.
Oaoiieiaey FR eiaao niaoeeaeueiue iaoaieci oi?aaeaiey iioieaie,
iicaieythuee iaania/eaaoue aieaa aeaeia ioeueoeieaene?iaaiea
?acii?iaeiiai o?aoeea.
Oi?aaeaiea iioieii — yoi i?ioeaaeo?a ?aaoee?iaaiey nei?inoe, n eioi?ie
ia?o?ooecaoi? iiaeaao iaeaou ia eiiiooaoi?. Anee i?eieiathuee eiiiooaoi?
ia a ninoiyiee i?eiyoue aua eaeea-eeai iaeaou (iai?eia?, ec-ca
ia?aa?ocee), oi i?e iiiiue aeaiiiai i?ioieiea iiaeii iio?aaiaaoue
i?einoaiiaeoue ioi?aaeo iaeaoia n ia?o?ooecaoi?a e, iinea ?aca?ocee,
i?iaeieaeeoue aa. Yoio i?ioeann aa?aioe?oao, /oi i?eieiathuaio
eiiiooaoi?o ia iaaei ioa?aeiauaaoue eaae?u. FR ia iiaeaea?aeeaaao yoio
i?ioieie a iieiie ia?a; anee o eiiiooaoi?a FR ia aeinoaoi/ii aooa?iiai
i?ino?ainoaa aeey i?eaia iinooiathueo eaae?ia, oi ii ioa?aeiauaaao
eaae?u n onoaiiaeaiiui oeaaii DE — ?ac?aoaiea ia ioa?aeiaeo (ni. ?en.
3). Iaeiaei, ia?o?ooecaoi? iiaeao eieoeeaeece?iaaoue i?ioeaaeo?o
ainnoaiiaeaiey aeaiiuo, /oi iiaeao i?eaanoe e aua aieueoaio caoi?o.
?enoiie 4. FECN e BECN.
?aoaiea yoie i?iaeaiu aiceaaaaony /anoe/ii ia i?ioieieu aa?oeaaeauaai
o?iaiy, iai?eia?, – TCP/IP, eioi?ue iiaeaea?aeeaaao iaeioi?oth noaiaiue
iaoaiecia oi?aaeaiey iioieaie, a oaeaea ia eniieueciaaiea aeoia FECN,
BECN — oeaaia yaiiai ecaauaiey i ia?aa?ocea a i?yiii e ia?aoiii
iai?aaeaieyo (ni. ?en. 4), i?e/ai iineaaeiea yaeythony iniaaiiinoyie FR.
Eioi?iaoeeiiiua aeou FECN e BECN aunoaaeythony a iiiaio iiiaaeaiey
eaae?a a caoi? o?aoeea. Ia?o?ooecaoi?u n eioa?oaenii FR iiaoo
?anoeo?iaaoue cia/aiey yoeo aeoia e aeoeaece?iaaoue oi?aaeaiea iioieii
ia aaca i?ioieiea aa?oeaaeauaai o?iaiy, iai?eia?, – TCP/IP.
Iaaei ioiaoeoue, /oi i?aaenoaaeaiiue iaoaieci ia aienaeny au a
eiioeaioeeth ?aaeaiaioe?iaaiey i?iioneiie niiniaiinoe naoe,
iiaeaea?aeeaaaioth FR, aac aaaaeaiey niaeaoaiey i niaeaniaaiiie nei?inoe
ia?aaea/e eioi?iaoeee (Committed Information Rate, CIR).
Eiioeaioeey niaeaniaaiiie nei?inoe ia?aaea/e eioi?iaoeee
CIR — ieieiaeueiay i?iioneiay niiniaiinoue, aa?aioe?iaaiiay eaaeaeiio
PVC eee SVC. Yoa nei?inoue (ecia?yaony a aeoao a naeoiaeo) auae?aaony
eeeaioii naoe FR a niioaaonoaee n iauaiii aeaiiuo, eioi?ua ii niae?aaony
ia?aaeaaaoue ii naoe, e aa?aioe?oaony iia iia?aoi?ii naoe FR eee
aaeieieno?aoi?ii. Ia oaeouee iiiaio nei?inoue aa?uee?oaony io 16 Eaeo/n
aei 44,8 Iaeo/n. Anee iaeaoiua iinueee ia i?aainoiaeyo nei?inoue ii?oa
iiaeeeth/aiey eeeaioa e i?iioneiay niiniaiinoue naoe FR a aeaiiue iiiaio
eiaao naiaiaeiua ?ano?nu, oi eeeaio iiaeao i?aauneoue niaeaniaaiiia
cia/aiea CIR. Nei?inoue, n eioi?ie eeeaio iinueaao aeaiiua i?e iaee/ee
aeinoaoi/iie i?iioneiie niiniaiinoe, iacuaaaony iverscription rate.
A neo/aa ia?aa?oaeaiiinoe naoe, eiiiooaoi?u ioa?anuaatho ecauoi/iua
(auoiaeyuea ca i?aaeaeu CIR) eaae?u. Iiea ?ac?aoaiey ia ioa?aeiaeo (DE)
a eaae?a FR iicaieyao ?aaoee?iaaoue yoio i?ioeann. Aeey eaaeaeiai
eaae?a, ia?anueaaiiai ii naoe, eiiiooaoi? FR onoaiaaeeaaao aeo DE, anee
aeaiiue eaae? i?aauoaao niaoeeoeeaoeeth CIR eeeaioa. A neo/aa caoi?a
eaae?u, n onoaiiaeaiiui oeaaii DE iiaoo auoue ioa?aeiaaiu.
?aaeueii, a naoyo FR, ia?yaeo n CIR eniieuecoaony on?aaeiaiiay ca
ii?aaeaeaiiue i?iiaaeooie a?aiaie Tc (neaaeai, ca iaeio naeoiaeo)
nei?inoue, eioi?oth naoue «iaycoaony» iiaeaea?aeeaaoue ii niaaeeiaieth
PVC eee SVC.
On?aaeiaiea ii a?aiaie ea?aao caeanue aaaeioth ?ieue. I?aaeiieiaeei, /oi
/a?ac eeieth aeinooia n i?iioneiie niiniaiinoueth 64 Eaeo/n
iieueciaaoaeue ii?aaeaeyao iaeii ae?ooaeueiia niaaeeiaiea n CIR, ?aaiie
32 Eaeo/n. Yoi cia/eo, /oi i?eiya, iai?eia?, a ia?aua iienaeoiaeu 32
Eaeo, eiiiooaoi? ai?aaa ioaa?aiooue ana inoaeueiua aeou, i?eoaaeoea ca
inoaeueiua iienaeoiaeu. Iiyoiio aaiaeeony iiiyoea niaeaniaaiiiai
eiioeueniiai iauaia ia?aaeaaaaiie eioi?iaoeee (Committed Burst Size —
Bc) — iaeneiaeueiiai iauaia aeaiiuo, eioi?ue naoue «iaycoaony»
ia?aaeaaaoue ca a?aiy Tc. Yoi a?aiy au/eneytho neaaeothuei ia?acii:
Tc=Bc/CIR, a ii naiae nooe iii i?iii?oeeiiaeueii ia?aaiiia?iinoe
o?aoeea.
Anee eaae?u ia oeeaaeuaathony a ?aiee, caaeaaaaiua ia?aiao?aie CIR e Bc,
oi iie ia?aaeathony n onoaiiaeaiiui aeoii DE. I?e yoii /anoi
eniieuecotho aua iaeei ia?aiao? — ecauoi/iue eiioeueniue iauai
ia?aaeaaaaiie eioi?iaoeee (Excess Burst Size — Be). Ii ii?aaeaeyao
iaeneiaeueiue iauai aeaiiuo naa?o An (ecauoi/iua aeaiiua), eioi?ue
eiiiooaoi? iiiuoaaony ia?aaeaoue a oa/aiea a?aiaie On (ni. ?en 4).
Aa?iyoiinoue aeinoaaee aeaiiuo Aa, ia?aaeathueony n onoaiiaeaiiui oeaaii
DE, i/aaeaeii, ieaea aa?iyoiinoe aeinoaaee aeaiiuo An. Ana aeaiiua,
i?aauoathuea iauai Aa, eiiiooaoi? ioa?aeiauaaao. Eae aeaeii ec ?enoiea
5, i?iioneiay niiniaiinoue eeiee aeinooia aeaeeony ia o?e ciiu:
niaeaniaaiiua aeaiiua, n aa?aioe?iaaiiie ia?aaea/ae;
ecauoi/iua aeaiiua (n onoaiiaeaiiui aeoii DE), eioi?ua ia?aaeathony a
caaeneiinoe io aeinooiiuo naoe ?ano?nia;
ana aeaiiua naa?o ecauoi/iuo, eioi?ua eiiiooaoi? aaoiiaoe/anee
ioa?anuaaao.
?enoiie 5. ?ani?aaeaeaiea i?iioneiie niiniaiinoe eeiee aeinooia i?e
i?aaiecaoeee /a?ac iaa ae?ooaeueiiai niaaeeiaiey n ii?aaeaeaiiuie CIR e
iaeneiaeueiie nei?inoueth ecauoi/iuo aeaiiuo
?aaeecaoeey yoeo i?aaee iiaeao nouanoaaiii ?acee/aoueny eae a
iai?oaeiaaiee FR ?acee/iuo i?iecaiaeeoaeae, oae e a naoyo eiiiaiee —
iinoaaueeia oneoa FR. Oe?iei eniieuecoaony neo/ae i?aaeinoaaeaiey
iieueciaaoaeth auai?a oieueei iaeiiai ia?aiao?a niaaeeiaiey — nei?inoe
CIR. I?e yoii a?aieoea ecauoi/iuo aeaiiuo ia?aaeaeaaaony «aaa?o» e
i?e?aaieaaaony nei?inoe ii?oa aeinooia. Oaeei ia?acii ono?aiyaony
«ia?oaay ciia», i?e iiiaaeaiee a eioi?oth aeaiiua aaoiiaoe/anee
na?anuaathony.
Eciaieoue CIR ia neiaeii — aeinoaoi/ii ia?aoeoueny e iia?aoi?o eee
aaeieieno?aoi?o naoe, eioi?ue a naith i/a?aaeue i?ia?aiiiui ia?acii
ia?aeiioeao?e?oao nenoaio. Ieeaeiai aeiiieieoaeueiiai iai?oaeiaaiey ia
o?aaoaony (i?e aeinoaoi/iii cia/aiee nei?inoe ii?oa onoaiiaeaiiiai o
iieueciaaoaey iai?oaeiaaiey).
Eoae, iiaeaaaeai eoia. Eiioeaioeey niaeaniaaiiie nei?inoe ia?aaea/e —
yoi iaoaieci niaeaniaaiey ni noaiaea?oii FR (i?aaeeaaathuei
?aaeaiaioe?iaaiioth i?iioneioth niiniaiinoue), i?aaeiacia/aiiue aeey
?ac?aoaiey caoi?ia a naoe, iin?aaenoaii ii?aaeaeaiey eeanna na?aena aeey
FR DTE e eiio?iey aeinooia iai?oaeiaaiey iieueciaaoaey e i?iioneiie
niiniaiinoe naoe. Aeey yoiai, i?e eiioeao?e?iaaiee niaaeeiaiey PVC
ii?aaeaeythony neaaeothuea ia?aiao?u CIR:
Bc (Committed Burst Size) – iauai aeaiiuo, ia?aaeaaaaiue aa?aioe?iaaiii
ca a?aiy Tc;
Be (Excess Burst Size) – iauai aeaiiuo iaae Bc, ia?aaeaaaaiue a neo/aa
aeinoaoi/iinoe ?ano?nia iieinu i?iioneaiey;
DE (Discard Eligibility) – oeaa ?ac?aoaiey ia ioa?aeiaeo;
Tc (sampling interval) a?aiaiiie eioa?aae aeey ecia?aiey Bc e Be, ?aaiue
Bc/CIR.
I?eaaaeai i?eia? eiioeao?aoeee PVC:
CIR=128000 bits per second
Bc=128000 bits
Be=64000 bits
Tc=1 second
A i?eaaaeaiiii i?eia?a, DTE iiaeao ia?aaeaaaoue aeaiiua ni n?aaeiae
nei?inoueth 128 kbps, eioi?ay iiaeao aic?anoaoue aei 192 kbps (Bc+Be).
Eaae?u ia?aaeaaaaiua iaae 128 kbps iiia/athony oeaaii DE. Eaae?u iaae
192 kbps aoaeoo na?ioaiu i?e aoiaea a naoue FR.
EIOAA?AOeEss ?A*E
Eae oaea auei ioia/aii, oaoiieiaey FR iicaieyao eniieueciaaoue aeey
ia?aaea/e /oanoaeoaeueiiai e caaea?aeeai o?aoeea (?a/ue e o. i.)
iaoaieci ?aca?ae?iaaiey iieinu eaiaea, aeeceee e oiio, eioi?ue
i?eiaiyaony i?e a?aiaiiii ?acaeaeaiee eaiaeia (iiae?iaii – ni.
i?aaeuaeouea ioieou), a aeey iau/iuo aeaiiuo — noaoenoe/aneia
i?ei?eoaoiia ioeueoeieaene?iaaiea. Ana yoi a niaieoiiinoe n iaeioi?uie
ae?oaeie iaoaieciaie (iienaiiuie a i?aaeuaeoueo ioieoao) iicaieyao
iaania/eoue iinoiyiiue oaii ia?aaea/e ?a/aauo iaeaoia.
Nia?aiaiiia iai?oaeiaaiea FR, iiieii eiii?annee ?a/e (a 10-15 ?ac),
iau/ii ?aaeecoao ?yae niaoeeaeueiuo aeai?eoiia aa ia?aaioee, eioi?ua
iicaieytho a aua aieueoae noaiaie eniieueciaaoue iniaaiiinoe o?aineyoeee
eaae?ia.
Iaeiei ec iaoaieciia yaeyaony iiaeaaeaiea iaoc. Eae i?aaeei, oaeaoiiiua
niaanaaeieee aiai?yo ii i/a?aaee. I?e ?acaiai?a ii iau/iiio oaeaoiio n
‘iie/auae’ noi?iiu ia?aaeaaony niaoeeaeueiue ooiiaie neaiae. E?iia oiai,
nouanoaotho iaocu iaaeaeo neiaaie e i?aaeeiaeaieyie. Ii noaoenoeea ai
a?aiy oaeaoiiiuo ia?aaiai?ia aieaa 60% iieinu i?iioneaiey eaiaea
eniieuecoaony ia ia?aaea/o oeoeiu. I?e aaoiiaoe/aneii ii?aaeaeaiee
ionoonoaey iieaciiai neaiaea anth iieino eaiaea iiaeii eniieueciaaoue
aeey ia?aaea/e aeaiiuo. Ia i?eaiiie noi?iia a yoi a?aiy aaia?e?oaony
‘?iciaue’ ooi, aeey oiai /oiau o iieueciaaoaey ia nicaeaaaeinue
aia/aoeaiey ‘ia?oaie’ eeiee.
Aua iaeiei eioa?aniui iaoaieciii yaeyaony ‘ia?aiaiiay nei?inoue
ioeeo?iaee’. Ii?aaeaeyaony iaeiaiueoay (aaciaay) nei?inoue ioeeo?iaee,
eioi?ay iaania/eaaao ieieiaeueii i?eaieaiia ea/anoai ia?aaea/e ?a/e, e
oi?ie?oaony iioie ‘aaciauo’ eaae?ia, a i?e iaee/ee naiaiaeiie iieinu
eaiaea — ‘aeiiieieoaeueiua’ iaeaou, oeo/oathuea ea/anoai ?a/e. Oaeie
aeai?eoi ia?aaioee oaeaoiiiiai o?aoeea eaaei ?aaeecoaony (iiae?iaii
?anniio?aiiuie auoa) n?aaenoaaie FR (eniieueciaaiea oeaaa DE a eaae?ao,
ia?aaeathueo ‘aeiiieieoaeueioth’ eioi?iaoeeth, /oi aeaao aiciiaeiinoue
naoe na?ineoue yoe eaae?u a neo/aa ia?aa?ocee).
I?eia? a?oeoaeoo?u naoe FR n eioaa?aoeeae ?a/e e aeaiiuo i?eaaaeai ia
?enoiea 6. Oaeaoiiiue o?aoee ia?aaeaaony iaiin?aaenoaaiii /a?ac o?iaie
FR, iaania/eaathuea aio i?ei?eoaoioth ia?aaea/o aac caaea?aeae, ii ia
aa?aioe?othuea 100%-iie aeinoaaee aei ocea iacia/aiey (eneaaeaiiua
eaae?u na?anuaathony).
?enoiie 6. I?eia? naoe Frame Relay n eioaa?aoeeae ?a/e
Aeey ia?aaea/e aeaiiuo, iiieii iaoaieciia FR iaaeno?aeueiie naoe, ia
aaiiaioneie noi?iia caaeaenoaiaaiu aeiiieieoaeueiua i?ioieieu, a aeaiiii
neo/aa X.25. Iie iaania/eaatho ca n/ao iiaoi?iie ia?aaea/e iaeaoia, a
eioi?uo iaia?oaeaiu ioeaee, aa?aioe?iaaiiia aeiaaaeaiea aeaiiuo ia
o?iaia aaiiaio-aaiiaio, oi anoue inouanoaeytho ooieoeee i?ioieiea
o?ainii?oiiai o?iaiy naieo?iaiaaie iiaeaee acaeiiaeaenoaey ioe?uouo
nenoai OSI (yoio iaoaieci ?anniio?ai a ioieoa ‘Iaoaieci oi?aaeaiey
iioieaie’).
N?AAeNOAA CAUEOU IO NAIAA
Inouanoaeaiea niaaeeiaiey ii aeiaaeueiie naoe naycaii n iaeioi?ie
iaii?aaeaeaiiinoueth, o. e. au ia aeaaeaaoa yoie naoueth e, oaeei
ia?acii, ia eiaaoa eiio?iey iaae o?aeoaie. A iiaeiaiuo neooaoeeyo
niaaeeiaiey ii aeiaaeueiie naoe, aeieaeiu auoue /?acau/aeii
ioeacionoie/eau. FR ioaa/aao yoiio o?aaiaaieth aeaaiaea?y iaania/aieth
aeeiaie/aneie ?aia?o?ooecaoeee a neo/aa ioeaca PVC.
Oece/anee naoe FR ia?acotho y/aenooth no?oeoo?o eiiiooaoi?ia (ni. ?en. 1
e ?en. 2). Iaeii ec i?aeiouanoa oaeie y/aenoie eiioeao?aoeee ninoieo a
oii, /oi iia iaania/eaaao ii?aaeaeaiioth noaiaiue ioeacionoie/eainoe.
Anee ec-ca auoiaea ec no?iy eaeiai eeai ocea PVC noaiiaeony
iaaeinooiiui, oi ninaaeiee eiiiooaoi? ia?aiai?aaeo niaaeeiaiea ii
aeueoa?iaoeaiiio eioi?iaoeeiiiiio eaiaeo. A ?acoeueoaoa oa?aeoa?enoeee
ia?aaea/e eeoue ianeieueei oooaeoaony. E?iia oiai, aeaaiaea?y oaeie
y/aenoie eiioeao?aoeee eiiiooaoi?u iiaoo iai?aaeyoue eaae?u a iaoiae
ae?oaeo eiiiooaoi?ia, anee oa eniuouaatho cia/eoaeueioth ia?aa?oceo.
Aeey caueou io naiaa ia o?iaia ocea iia?aoi?u eee aaeieieno?aoi?u FR
i?aaeeaaatho aeaa iioeee: caianiua e ?aca?aiua PVC. A neo/aa caianiiai
niaaeeiaiey (standby PVC) PVC onoaiaaeeaaaony e aeoeaece?oaony a
caianiii ocea; yoio eaiae eiaao nouanoaaiii iaiueooth nei?inoue CIR, /ai
iniiaiia PVC. Anee aae?oa ocae iino?aaeaao io caieao?ynaiey eee iiaea?a,
oi caianiia PVC aoaeao aeoeaece?iaaii i?aeoe/anee iaiaaeeaiii.
A neo/aa ?aca?aiiai niaaeeiaiey (backup PVC) PVC onoaiaaeeaaaony ia
caianiie ieiuaaeea, ii ia aeoeaece?oaony. Anee ooieoeeiie?iaaiea
iniiaiiai ocea iaaiciiaeii, PVC aoaeao aeoeaece?iaaii. Caianiia PVC
iiaeoiaeeo aeey iaeaaaeiaeoeo i?eeiaeaiee aeaaiaea?y oiio, /oi aai
aieinoue iiaeao auoue a?aiaiii oaaee/aia aeey i?aaeinoaaeaiey aieaa
aunieie i?iioneiie niiniaiinoe; aaeieieno?aoi?o naoe aeinoaoi/ii oieueei
i?ia?aiiiiai aiaoaoaeuenoaa a eiioeao?aoeeth naoe e aoaeao
i?aaeinoaaeaia aeiiieieoaeueiay i?iioneiay niiniaiinoue aei oao ii?,
iiea iniiaiie eaiae ia aoaeao ainnoaiiaeai.
Iienaiiue iiaeoiae FR e caueoa io naiaa aieaa aeaie e iaiaa
aei?iainoiyu, iaaeaee o TDM. A neo/aa TDM au aeieaeiu aoaeaoa eiaoue
ianeieueei caianiuo auaeaeaiiuo eeiee. Oaeay eiioeao?aoeey e aei?iaa e
neiaeia. Iinea aaa?ee aaeieieno?aoi?o i?eaeaony ia?aeiioeao?e?iaaoue ana
iai?oaeiaaiea, a oii /enea ia?o?ooecaoi?u e CSU/DSU.
IAAeINOAOEE OAOIIEIAEE
Iniiaiie iaaeinoaoie oaoiieiaee FR neaaeoao ec oiai, /oi FR yaeyaony
i?ioieieii eaiaeueiiai (aoi?iai a iiaeaee OSI) o?iaiy. FR ‘ia ?acee/aao’
i?ioieieu auoaeaaeaueo o?iaiae. Ec yoiai auoaeaao iiiaeanoai i?iaeai.
Iai?eia?, aeaaea anee a naoe eniieuecoaony iaeei i?ioieie naoaaiai
o?iaiy, neaaeai IP, FR ia ‘ioee/eo’ o?aoee aeeciaiii aaaeiiai aeey
?aaiou i?aaei?eyoey i?eeiaeaiey eeeaio-na?aa? io aeinoaoi/ii
aoi?inoaiaiiiai o?aoeea, eaeouaai n na?aa?a Web. Iaeei ec niiniaia
ioaeaeeoue yoe o?aoeee ae?oa io ae?oaa — eniieueciaaoue aeey eaaeaeiai
ec ieo naia ae?ooaeueiia niaaeeiaiea, /oi, ai?i/ai iio?aaoao
aeiiieieoaeueiuo ?anoiaeia ia aoi?ia ae?ooaeueiia niaaeeiaiea.
N?aaee i?i/eo i?iaeai iiaeii iacaaoue iia?aoeee IP-ioeueoeeanoeiaa,
ionoonoaea oe?ieiaauaoaeueiiai iiiaeanoaaiiiai aeinooia (Non-Broadcast
Multiple Access – NBMA) e ae?.
EETH*AAUA AeIEOIAIOU NOAIAeA?OA FRAME RELAY
ANSI TI.602
ISDN-Data-Link Layer Signaling Specification for Application at the
User-Network Interface ii?aaeaeyao i?ioeaaeo?o aeinooia e nayce ia
D-eaiaea (LAPD). FR eniieuecoao iiaeiiiaeanoai LAPD iacuaaaiia ‘core
aspects’ (aeineiaii — ‘aeae ia yae?i’).
ANSI TI.606
ISDN-Architectural Framework and Service Description for Frame Relaying
Bearer Service aeeth/aao iienaiea a?oeoaeoo?u e na?aena FR.
ANSI Addendum to TI.606
Frame Relaying Bearer Service aeeth/aao aeaoaeueiia iienaiea iaoaieciia
oi?aaeaiey iioieaie.
ANSI TI.618
ISDN-Core Aspects of Frame-Relay Protocol for use with Frame Relaying
Bearer Service aeeth/aao iienaiea yae?a i?ioieiea FR.
ANSI TI.607 e ANSI TI.617
ISDN-Layer 3 Signaling Specification for Circuit-Switched Bearer Service
for Digital Subscriber Signaling System No.1 e ISDN-Digital Subscriber
Signaling System No.1 – Signaling Specification for Frame-Relay Bearer
Service. Ii?aaeaeytho o?aaiaaiey e neaiaeecaoeee aeey FR SVC e PVC
na?aena.
IIEIAEAIEA NAOAE FRAME RELAY IA ?UIEA
II*AIO FRAME RELAY ?
O aaoi?ia anao noaoae, ioaeeeoaiuo ii oaiaoeea FR, oaeo oiai, /oi FR
ethaei eiia/iuie iieueciaaoaeyie e, /oi o?aaeeoeeiiiui iia?aoi?ai naoae
e aeueoa?iaoeaiui iinoaaueeai oneoa auaiaeii ?acaa?ouaaoue naoe FR, ia
aucuaaao niiiaiee. A NOA ia?aoiae iieueciaaoaeae io a?aiaeiaaiiuo eeiee
e FR naycai n oai, /oi yoi iicaieyao ei nieceoue iauea naoaaua ?anoiaeu
ia 25-50%. Iaiiiiei, /oi FR —iaeaieaa yooaeoeaiay oaoiieiaey (aeaoaaay e
i?inoay a oi?aaeaiee) aeey ia?aaea/e i/aiue ia?aaiiia?iiai o?aoeea EAN e
i?aaiecaoeee iaaenaoaaiai iaiaia. Aeiiieieoaeueiui i?aeiouanoaii
yaeyaony oi, /oi /anoiua e iauaaeinooiiua naoe FR iicaieytho aanieaoii
ia?aaeaaaoue ?a/aaie o?aoee. N oi/ee c?aiey iia?aoi?ia naoae nayce,
a?aiaeoaiua eeiee, ianiio?y ia naith aunieoth aeioiaeiinoue, ia naiii
aeaea ia yooaeoeaiu. Iicaieyy ianeoaeeoue aieueoia /enei iieueciaaoaeae
n iiiiuueth iaeiie eeiee nayce, oaoiieiaey FR aeaao aiciiaeiinoue
iia?aoi?ai a iieiie ia?a eniieueciaaoue aieinoue naieo naoae.
?acaeaeaiea iieinu i?iioneaiey iaaeaeo iiiaeanoaii ae?ooaeueiuo
niaaeeiaiee FR nieaeaao noieiinoue aeinooia e naoe e oiaiueoaao
o?aaoaioth n?aaeithth iieino i?iioneaiey. Aieueoeinoai i?eeiaeaiee
caa?oaeatho naoue i/aiue ia?aaiiia?ii, iiyoiio ?acaeaeyaiia
eniieueciaaiea aunieinei?inoiiai eaiaea eiaao cia/eoaeueiua i?aeiouanoaa
(ii i?iecaiaeeoaeueiinoe) ia?aae i?eiaiaieai ieceinei?inoiiai
auaeaeaiiiai eaiaea.
Aeey aeueoa?iaoeaiuo iinoaaueeia oneoa nayce oaoiieiaey FR eiaao aua
aieueoa i?aeiouanoa. N aa iiiiuueth iie iiaoo i?aaeeiaeeoue oneoae
ia?aaea/e aeaiiuo, eioi?ua i?aeoe/anee ionoonoaiaaee ai iiiaeo no?aiao.
Ii ia?a caaa?oaiey Oi?oiii FR ?ac?aaioee noaiaea?oia, eanathueony
neaiaeecaoeee, naeaoey e ia?o?ooecaoeee ?a/aaiai o?aoeea,
aeueoa?iaoeaiua iinoaaueee oneoa iiaoo i?eaea/ue e naaa /anoue ?a/aaiai
o?aoeea o?aaeeoeeiiiuo iia?aoi?ia nayce.
NIINIAU IINO?IAIEss NAOE FRAME RELAY
Oneoae FR i?aaeeaaatho ana aieueoa e aieueoa oaeaeiiioieeaoeeiiiuo
eiiiaiee ai anai ie?a. Eae i?aaeei, iie ecaeaeatho iaeneiaeueioth
iieueco ec yoie oaoiieiaee iooai eioaa?e?iaaiiie ia?aaea/e ii naoe FR
aeaiiuo, o?aoeea EAN, ?a/e e oaenia. I?e iino?iaiee ei?ii?aoeaiie naoe
ia aaca oaoiieiaee FR, eae i?aaeei, ?anniao?eaathony o?e iniiaiuo
aa?eaioa aa i?aaiecaoeee.
*anoiay naoue ia aaca auaeaeaiiuo eeiee. Eiiiaiey a?aiaeoao eeiee nayce
e i?eia?aoaao iaiaoiaeeiia iai?oaeiaaiea (eiiiooaoi?u, ia?o?ooecaoi?u
eee ioeueoeieaeni?u). Iino?iaiiay ia eo aaca naoue yaeyaony
nianoaaiiinoueth oe?iu e iaoiaeeony iiae aa iieiui eiio?ieai.
Ae?ooaeueiay /anoiay naoue. Oe?ia iieoiaao oneoae naoae FR o
oaeaeiiioieeaoeeiiiuo eiiiaiee. I?e yoii iia eeai i?eia?aoaao
aaiiaioneia iai?oaeiaaiea FR aianoa n oneoaaie eee iacaaeneii io ieo,
eeai a?aiaeoao yoi iai?oaeiaaiea o oaeaeiiioieeaoeeiiiiai iia?aoi?a.
Oaeei ia?acii, oe?ia nicaeaao /anoioth ei?ii?aoeaioth naoue n
eniieueciaaieai oneoa naoae FR iauaai iieueciaaiey e inouanoaeyao iieiue
eiio?ieue iaae naoueth e aaeieieno?aoeaiia oi?aaeaiea ath.
Niaeaoaiea n aiaoiae i?aaiecaoeeae i nicaeaiee e oi?aaeaiee naoueth.
Nouanoaothuay ei?ii?aoeaiay naoue ia?aaeaaony oaeaeiiioieeaoeeiiiie
eiiiaiee, eioi?ay inouanoaeyao aaeieieno?aoeaiia oi?aaeaiea yoie naoueth
a eioa?anao oe?iu-eeeaioa, a e?iia oiai, i?aaeinoaaeyao oneoae nayce,
iai?oaeiaaiea e ?aaeecoao iiaeaea?aeeo naoe. Nouanoaoao y?ei au?aaeaiiay
?uii/iay oaiaeaioeey e oaeei niaeaoaieyi; ia aeaiiie iniiaa a ie?a
ooieoeeiie?oao 30% ei?ii?aoeaiuo naoae. Yoa oaiaeaioeey iaoneiaeaia eae
ianiiniaiinoueth eee iaaeaeaieai iiiaeo eiiiaiee naiinoiyoaeueii
ni?aaeyoueny n aei?iainoiyuae e neiaeiie yenieoaoaoeeae ei?ii?aoeaiuo
naoae, oae e aeiaaeueiie yeniaineae oaeaeiiioieeaoeeiiiuo iia?aoi?ia,
eioi?ua iinoiyiii ?anoe?ytho niaeo? i?aaeinoaaeyaiuo oneoa.
INIIAIUA OAIAeAIOeEE ?UIEA
Iacaaeneii io niiniaa nicaeaiey naoe FR, eiiiaiee iaiaoiaeeii eiaoue
i?aaenoaaeaiea ia eiathuainy ia ?uiea iia?aoi?neii e aaiiaioneii
iai?oaeiaaiee FR. Iiiaea iinoaaueee i?aaeeaaatho ono?ienoaa aeinooia e
naoyi FR (Frame Relay Access Device – FRAD) n eioaa?aoeeae ?a/e e
aeaiiuo. I?e auai?a FRAD iaiaoiaeeii o/eouaaoue ?acia? naoe e
ia?niaeoeau aa ?anoe?aiey. Iai?oaeiaaiea aeieaeii eiaoue aeaeea
oa?aeoa?enoeee, eioi?ua iicaieytho i?eniiniaeoue aai e oai oaiaeaioeeyi
a iaeanoe oaoiieiaee e i?aaiecaoeee naoae, eioi?ua aoaeoo
aeaaainoaothueie /a?ac 2 -3 aiaea.
Ieaea i?eaaaeaiu iniiaiua oaiaeaioeee ?uiea iai?oaeiaaiey oneoa FR.
?ino o?aaiaaiee e i?iioneiie niiniaiinoe eaiaeia FR, iaania/eaathueo
aunieinei?inoioth ia?aaea/o eioi?iaoeee n iiiiuueth iaaei?iaeo n?aaenoa
aeinooia e ?ano?nai T1/E1. I?aaeiieaaaeinue, /oi naoe FR aoaeoo
iiaeaea?aeeaaoue nei?inoe ia?aaea/e aei 2 Iaeo/n, a oneoae
oe?ieiiieiniuo eaiaeia — i?aaeinoaaeyoueny a naoyo ATM. Iaeiaei
iia?aoi?u ia/eiatho ?anoe?youe niaeo? naieo oneoa FR, i?aaeeaaay ana
aieueoea nei?inoe ia?aaea/e. Oae MCI oaea iaania/eaaao a iauaaeeiaiiii
eaiaea FR nei?inoe ia?aaea/e 12,88 Iaeo/n. Oaeei ia?acii FRAD aeieaeiu
?aaioaoue ia aunieeo nei?inoyo.
Iauaaeeiaiea aeinooia a Internet e a ae?ooaeueiua /anoiua naoe.
Iia?aoi?u i?aaeeaaatho yeiiiie/iue aeinooi a Internet /a?ac naoe FR, /oi
iicaieyao ca n/ao ioeaca io oneoa io oneoa iinoaaueea aeinooia a
Internet oaaee/eoue aa?aioe?iaaiioth nei?inoue ia?aaea/e eioi?iaoeee
(CIR). A yoii neo/aa iiaeii eniieueciaaoue iaeii e oi aea iai?oaeiaaiea
aeey aeinooia a naoe FR e a Internet (ia?aie eanoi/eie yaeyaony AT&T). A
oeeeaeao ?aeiiaiaeoaony onoaiaaeeaaoue eioaeeaeooaeueiua FRAD n
eioaa?aoeeae ?a/e e aeaiiuo, niiniaiua iaeiia?aiaiii auiieiyoue ooieoeee
IP-ia?o?ooecaoi?a, aooaioeoeeaoeee iieueciaaoaey e a?aiaeiaoy?a, a oae
aea eniieueciaaoue iaeei IP-aae?an aeey anao ono?ienoa EAN.
Iiaen/eoaii, /oi 60% e?eoe/iiai o?aoeea a NOA ninoaaeytho aeaiiua SNA.
Eiiiaiee ia?aaiaeyo iiiaea ec yoeo naoae ia oaoiieiaeth FR. Aeaaiaea?y
caiaia aei?iainoiyueo auaeaeaiiuo eeiee SDLC aeinoeaaaony nieaeaiea
ecaea?aeae ia 30-40%. Aeaiiua SNA ia?aaeathony ii aeiaaeueiui naoyi FR
ia?yaeo n o?aoeeii EAN, iiyoiio iai?oaeiaaiea FR aeieaeii iaania/eaaoue
iauaaeeiaiea o?aoeea SNA e EAN a eaiaeao FR.
Niaianoeiiiinoue n AOI. Iia?aoi?u i?aaeeaaatho oneoae FR a ea/anoaa
i?iiaaeooi/iiai ?aoaiey aeey iieueciaaoaeae, ioaeaeathueony a aunieie
i?iioneiie niiniaiinoe. E?iia oiai, oaea nae/an a ei?ii?aoeaiuo naoyo
oaoiieiaey AOI eniieuecoaony ia e?oiiuo iauaeoao, a a iaaieueoeo
oeeeaeao i?iaeieaeaao i?eiaiyoueny oaoiieiaey FR. Auei au oi?ioi, anee
au aaiiaioneia iai?oaeiaaiea FR iiaei iaania/eaaoue ia?aoiae e AOI n
iiiiuueth aiaoiaai ?aoaiey (ono?ienoai iauaaeeiaiey AOI/FR).
?ino eiee/anoaa eio?anaoae. 75% eio?anaoae eniieuecotho a ea/anoaa
o?ainii?oiiai i?ioieiea FR. AEaeaoaeueii ?aniieaaaoue iai?oaeiaaieai FR,
eioi?ia iiaeaea?aeeaaao ia?aaea/o ?a/e eae ii i?ioieieo FR (VoFR), oae e
ii IP (VoIP).
IAI?OAeIAAIEA E EAIAEU AeEss NAOAE FRAME RELAY
INIIAIUA E?EOA?EE AUAI?A IAI?OAeIAAIEss
A yoii ioieoa i?eaaaeaiu iniiaiua e?eoa?ee auai?a iai?oaeiaaiey aeinooia
a naoe FR, eioi?ia niiaeao oaeiaeaoai?eoue ia oieueei iuiaoiea, ii e
aoaeouea iio?aaiinoe ei?ii?aoeaiie naoe.
Oieaa?naeueiinoue ?aoaiee e aiciiaeiinoue ia?aueaaiey:
iaeei iinoaauee — ia/eiay io ?aoaiey iaeiai ioena aei eiiioieeaoeeiiiie
ieaooi?iu aeey oi?aaeaiey e?oiiie eiiiaieae. Yoei aeinoeaaaony
nie?auaiea ?anoiaeia ia i?eia?aoaiea iai?oaeiaaiey e ia ?anoe?aiea aai
aiciiaeiinoae a aoaeouai;
eioaa?aoeey ?a/e, aeaiiuo, oaeneieeueiuo niiauaiee e o?aoeea EAN
iicaieyao eniieueciaaoue iaeneioi i?iioneiie niiniaiinoe naoe;
iiaeaea?aeea iaaeno?aeueiiai eaiaea n aunieie i?iioneiie niiniaiinoueth
(io n*64 Eaeo aei 2 Iaeo/n).
Iiaeaea?aeea ia?aaea/e ?a/e:
eiii?anney ii noaiaea?oo G.729 (?aeiiaiaeiaai e eniieueciaaieth
eiini?oeeoiii FR Forum);
i?ei?eoaoiay ia?aaioea ?a/aauo iaeaoia;
iiaeaea?aeea eioa?oaenia o/?aaeaeai/aneie AON aeey ianeieueeeo eaiaeia
T1/E1;
eiiiooaoeey ?a/e — onoaiiaeaiea nayce iaaeaeo ianeieueeeie ioieoaie e
aaoiiaoe/aneay ia?o?ooecaoeey oaeaoiiiiai auciaa a i?aaeaeao
ei?ii?aoeaiie naoe a iaoiae o/?aaeaeai/aneie AON;
eniieueciaaiea nia?aiaiiuo oaoiieiaee — aooa?a oaciaiai ae?iaeaiey;
iiaeaaeaiey ?a/aauo iaoc e yoa;
iiaeaea?aeea neaiaeecaoeee (QSIG, ISDN);
oe?ieee auai? oaeaoiiiuo eioa?oaenia (E&M, FXS, FXO).
Iiaeaea?aeea ia?aaea/e aeaiiuo
ia?o?ooecaoeey i?ioieieia IP e IPX;
iiiaii?ioieieueiay iiaeaea?aeea SNA (RFC 1490), IP, IPX, HDLC,
aneio?iiiue X.25;
iiaeaea?aeea na?aenia ISDN; niaaeeiaiea ii o?aaiaaieth (COD), iieina
i?iioneaiey ii o?aaiaaieth (BOD), aaoiiaoe/aneia iiaeeeth/aiea
?aca?aiiai eaiaea ISDN;
iiaeaea?aeea ooieoeee a?aiaeiaoy?a;
eniieueciaaiea iaeiiai IP-aae?ana aeey anao ono?ienoa EAN;
ano?iaiiua ono?ienoaa DCU/CSU aeey iiaeeeth/aiey e naoe DDS;
eiii?anney aeaiiuo.
Oi?aaeaiea.
Onoaiiaeaiiua a ono?ienoaa i?ia?aiiu-aaaiou SNMP e i?eeiaeaiea naoaaiai
aaeieieno?e?iaaiey aeieaeiu a iieiie ia?a iaania/eaaoue
eiioeao?e?iaaiea, aeeaaiinoeeo e iai?a?uaiue eiio?ieue n oeaio?aeueiie
eiiniee oi?aaeaiey.
?aca?ae?iaaiea.
Iaiaoiaeeii iaee/ea ?aca?aiuo iaaeno?aeueiiai ii?oa, iiaeoey oi?aaeaiey
e enoi/ieea ieoaiey.
EAIAEU AeEss FR
Eae iieacae iiuo, a oii /enea ?inneeneee, aeey yoie oeaee iiaoo
neoaeeoue neaaeothuea eaiaeu.
Oeeo?iaua auaeaeaiiua eaiaeu nayce. Eo eniieueciaaiea yaeyaony iaeaieaa
i/aaeaeiui e anoanoaaiiui aa?eaioii, anee anoue n?aaenoaa ia eo
?acaa?ouaaiea.
Oece/aneea eeiee. Anee i?aaiecaoeey eiaao oece/aneea (iaoieioiaiiua)
eeiee, oi i?e iiiiue niioaaonoaothueo iiaeaiia (aeeaeiaai aeaenoaey eee
HDSL) iiaeii iieo/eoue iaeiaeaiiua oeeo?iaua eaiaeu ni nei?inoueth
ia?aaea/e aei 2 Iaeo/n. Aac i?eiaiaiey ?aieoa?ia oaeea eaiaeu
iaania/eaatho naycue ia ?annoiyiee aei 16 ei. I?e/ai aeaeueiinoue nayce
ia?aoii i?iii?oeeiiaeueia aeeaiao?o i?iaiaea e nei?inoe ia?aaea/e. Ia
iioiaieieia i?e iiiiue iiaeaiia RAD iiaeii aeinoe/ue auno?iaeaenoaey aei
38 Iaeo/n (E3).
Auaeaeaiiua eaiaeu oiiaeueiie /anoiou (O*). Iiiai/eneaiiua yenia?eiaiou
e i?aeoe/aneay yenieoaoaoeey naoae FR (iniaaiii a ?innee) iiaeoaa?aeeee
aiciiaeiinoue eniieueciaaiey eaiaeia O* a naoyo FR. I?e yoii iaiaoiaeeii
i?eiaiaiea ea/anoaaiiuo i?ioanneiiaeueiuo iiaeaiia, iinoiyiiia neaaeaiea
ca ninoiyieai eaiaeia, a oae aea iioeiecaoeey oiiieiaee naoae. I?e
iino?iaiee naoe FR ia aaca eaiaeia O* neaaeoao ecaaaaoue oiiieiaee n
aieueoei eiee/anoaii i?iiaaeooi/iuo oceia, eia/a FR aoaeao ?aaioaoue
iayooaeoeaii.
CAEETH*AIEA
Eiia/ii, FR ia iiaeao aa?aioe?iaaoue ea/anoai ianeoaeeaaiey ia oii
o?iaia, eioi?ue niiniaia i?aaeinoaaeoue AOI, e ia eiaao ?acaeouo
iaoaieciia oi?aaeaiey i?iioneiie niiniaiinoueth, naienoaaiiuo AOI. Oai
ia iaiaa nouanoaoao iaiaei i?e/ei (/anoe/ii i?eaaaeaiiuo auoa),
ii?aaeaeythueo oniao ?acaeoey naoae FR e aea?eaeiuo naoae AOI-FR.
Nouanoaoao aeaaea iiaiea, /oi a ianoiyuaa a?aiy ?acaeoea naoae AOI
io/anoe naycaii n nouanoaiaaieai oaoiieiaee FR, eioi?ay aeaao aeey ieo
iioiee.
NIENIE EEOA?AOO?U
AEo?iae «Naoe», 5/97
AEo?iae «Naoe e nenoaiu nayce», 3/97
AEo?iae «Naoe e nenoaiu nayce», 5/97
AEo?iae «Naoe», 6/97
AEo?iae «LAN», oii 3, No610/97
AEo?iae «Oaoiieiaee e n?aaenoaa nayce», No2, aaaono-naiya?ue/97
+ ?aciue Eioa?iao
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