Stacking Tags in LLC Media

Transcription

1 Scking Tgs in LL Medi Normn Finn ugus 19, 2013 Ver. 2 (This presenion is lso uploded o documen sysem s documen number ) bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 1

2 Work now in progress on P802.1Qbz nd P802.11k hs shown h he mehod currenly defined in IEEE 802.1Q for dding nd removing gs (e.g., he VLN g) o frmes on LL medi (e.g., ) is unenble. new scheme is proposed in P802.1Qbz Drf 1.2 for use by P802.11k. In he wors cse, his chnge could invlide currenlycomplin implemenion of This presenion solicis commens from ny orgnizion or individul h migh be ffeced by his chnge. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 2

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4 Oces: Frme onrol Durion/ ID ddress 1 ddress 2 ddress 3 Sequence onrol ddress 4 QoS onrol HT onrol Frme Body FS M Heder Figure 8-30 D frme mc_service_d_uni () IEEE Sd bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 4

5 802.3 Oces vr. PREMBLE SFD D S LENGTH / TYPE M LIENT DT FS EXTE NSION mc_service_d_uni () IEEE Sd bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 5

6 Lengh/Type EherType d (e.g. IP pcke): LL d (e.g. Bridge Proocol D Uni [BPDU]):. 2 M LENGTH / TYPE TYPE > 05-FF. 2 3 N 3 LENGTH / TYPE LENGTH < 05-DD M LIENT DT M LIENT DT IP heder IP d M LIENT DT LL, LL - d N BPDU SNP: N 8 LENGTH / TYPE LENGTH < 05-DD LL, LL = - OUI or 0 N M LIENT DT EherType or subype IP heder d IP d bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 6

7 LL M EherType d (e.g. IP pcke): LL, LL = EherType IP heder d IP d LL d (e.g. Bridge Proocol D Uni [BPDU]): 3 M LL, LL - d BPDU M Oher SNP: LL, LL = - OUI subype d --03 PQ-RS-TU WX-YZ propriery proocol bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 7

8 Lengh/Type no g: Lengh/Type gged: Simply dd or remove g; is unchnged.. 2 N 2 LENGTH / TYPE M LIENT DT. 2 L 2 N 2 EherType Tg vlue LENGTH / TYPE M LIENT DT LL no g: LL gged: Simply dd or remove g; is unchnged. 3 M 3 LL. 6 2 L 3 M 3 d SNP EherType Tg vlue LL d bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 8

9 On LL medi, he firs 3 byes following every g re LL. On Lengh/Type medi, he firs 2 byes following every g re Lengh/Type. You know how o decode he whole frme, becuse you know wheher he medium is LL or Lengh/Type. You cnno ell from he d, iself, wheher he byes following g re LL or Lengh/Type, becuse here re mny wo-byes vlues h re vlid in boh forms. Knowledge of he medi ype is essenil. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 9

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11 ll gs mus be rnsled once problem E1 B2 B2 B3 B4 B5 E2 Lengh/Type gs on medi B I B I LL LL gs on LL medi d S Q d S Q d d d LL LL d LL S Q LL S Q LL LL LL LL Q 802.1Q decoder ring: B = Bckbone ddresses, I = I-g, = usomer ddresses, S = Service VLN gs, Q = usomer VLN gs. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 11

12 Tgging ner he edges of he nework mus be in he form expeced by he medium in h re. Oherwise, hey cnno decode he g sck. We cnno, ex pos fco, require every bridge nd g-wre end sion o sr rnsling beween encpsulions. Heurisics o do he rnslion re possible, bu no relible. We could sk he bridge h connecs o wo medi ypes o conver ll gs nd he originl. Th is difficul o do in high speed in SIs. I mkes i impossible o deploy new gs he edge, becuse he core devices will no know how long hose gs re. Th s how you know i is violion of he principles of lyering. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 12

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14 Lengh/Type no g: Lengh/Type gged: Simply dd or remove g; is unchnged.. 2 N 2 LENGTH / TYPE M LIENT DT. 2 L 2 N 2 EherType Tg vlue LENGTH / TYPE M LIENT DT LL no g: LL gged: hnge when dding or removing g. 3 M 3 LL. 6 2 L 2 N 2 d SNP EherType Tg vlue LENGTH / TYPE M LIENT DT bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 14

15 LL M dd/remove g on SNP frme LL, LL = Ungged EherType IP heder d IP d L 2 M Tgged TG Ungged LL, LL = - 0 EherType Tg vlue EherType d IP heder IP d dd: onver old ouer iem LL à, dd LL g. Remove: Delee LL g, conver new ouer iem à LL. OR: dd/remove g beween LL-SNP nd. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 15

16 LL 3 M dd/remove g on LL frme Ungged LL, LL - d BPDU M Tgged MSGU TG Ungged LL, LL = - 0 EherType Tg vlue Lengh LL, LL - d M BPDU dd or remove boh he LL g nd he Lengh field. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 16

17 One rnslion per g or medi chnge soluion E1 B2 B2 B3 B4 B5 E2 Lengh/Type gs on medi B I B I LL LL gs on LL medi d S Q d S Q d d d d S Q S Q LL LL Q 802.1Q decoder ring: B = Bckbone ddresses, I = I-g, = usomer ddresses, S = Service VLN gs, Q = usomer VLN gs. Normn Finn, isco Sysems bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 17

18 Muliple gs on Lengh/Type (802.3) frme: Lengh/Type Tg 1 Lengh/Type Tg 2 Lengh/Type Tg 3 Lengh/Type Muliple gs on LL (802.11) frme: LL SNP Tg 1 Lengh/Type Tg 2 Lengh/Type Tg 3 Lengh/Type Only he firs iem is LL-encoded on n LL medium; ll oher iems re Lengh/Type-encoded. (n ungged is LL or Lengh/Type, by medium.) bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 18

19 We keep he whole sck, excep for he ouermos iem, in Lengh/Type form. Every device knows how o encode/decode frmes. Only one iem is convered per g dded or removed. The ouermos iem sill follows he rules for he medium in quesion. We could eqully well hve used he LL form in ll excep he ouermos iem, excep h devices lredy use muliple gs nd (s fr s his uhor knows) devices do no use LL-scked gs. (There is lso new EherType defined in P802.1Qbz D1.2 o encode n LL longer hn 1500 byes.) bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 19

20 If ny cul use of he LL-scked g form is known, plese le Inerworking TG nd TGk know bou i, becuse we propose o remove his form from he sndrds:. 6 2 L 6 2 M SNP EherType Tg vlue SNP EherType d IP heder IP d No lengh field! If here is such use, hen we will hve o re-exmine our opions. bz-nfinn-ll-g-scking-0813-v01 IEEE inerim meeing, Sep. 2013, York, UK 20

21 Thnk you.