One document matched: draft-ietf-rmt-bb-gra-signalling-01.ps

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/F0 10/Courier-Bold@0 SF(Internet Engineering Task Force)72 85 Q(RMT WG)
210 E 228(INTERNET-DRAFT Tony)72 98 R(Speakman/Cisco)6 E 66
(draft-ietf-rmt-bb-gra-signalling-01.ps Lorenzo)72 111 R(Vicisano/Cisco)
6 E(21 January 2003)414 124 Q(Expires: July 2003)396 137 Q/F1 14
/Times-Bold@0 SF(Reliable Multicast T)155.112 162 Q
(ransport Building Block)-1.036 E(Generic Router Assist - Signalling Pr)
119.741 175 Q(otocol Speci\214cation)-.252 E/F2 11/Times-Bold@0 SF
(Status of this Document)72 220 Q/F3 11/Times-Roman@0 SF
(This document is an Internet-Draft and is subject to all pro)72 236.6 Q
(visions of Section 10 of RFC2026.)-.165 E(Internet-Drafts are w)72
262.6 Q(orking documents of the Internet Engineering T)-.11 E(ask F)-.88
E(orce \(IETF\), its areas,)-.165 E(and its w)72 275.6 Q(orking groups.)
-.11 E(Note that other groups may also distrib)5.5 E(ute w)-.22 E
(orking documents as)-.11 E(Internet-Drafts.)72 288.6 Q
(Internet-Drafts are draft documents v)72 314.6 Q
(alid for a maximum of six months and may be updated,)-.275 E
(replaced, or obsoleted by other documents at an)72 327.6 Q 2.75(yt)
-.165 G 2.75(ime. It)-2.75 F(is inappropriate to use Internet- Drafts)
2.75 E(as reference material or to cite them other than as "w)72 340.6 Q
(ork in progress.")-.11 E
(The list of current Internet-Drafts can be accessed at http://www)72
366.6 Q(.ietf.or)-.715 E(g/1id-abstracts.html)-.198 E
(The list of Internet-Draft Shado)72 392.6 Q 2.75(wD)-.275 G
(irectories can be accessed at http://www)-2.75 E(.ietf.or)-.715 E
(g/shado)-.198 E -.715(w.)-.275 G(html).715 E
(This document is a product of the IETF RMT WG.)72 418.6 Q
(Comments should be addressed to the authors)5.5 E(or to the WG')72
431.6 Q 2.75(sm)-.605 G(ailing list at rmt@ietf.or)-2.75 E(g.)-.198 E F2
2.024 -1.012(To t)72 457.6 T
(he extent that it applies, this document is in conf)1.012 E
(ormance with the r)-.275 E(equir)-.198 E(ements of)-.198 E
(Section 2.1 of RFC3269.)72 470.6 Q(Lexical Con)72 509.6 Q -.11(ve)-.44
G(ntions).11 E F3(The k)72 526.2 Q .33 -.165(ey w)-.11 H
(ords "MUST", "MUST NO).055 E(T", "REQ)-.44 E
(UIRED", "SHALL", "SHALL NO)-.11 E(T",)-.44 E("SHOULD", "SHOULD NO)72
539.2 Q(T", "RECOMMENDED", "MA)-.44 E(Y", and "OPTION)-1.155 E
(AL" in this)-.385 E
(document are to be interpreted as described in RFC2119.)72 552.2 Q F2
(Abstract)267.534 571.2 Q F3(This draft speci\214es the signalling prot\
ocol to be implemented in both end systems and)97 593.8 Q(netw)97 606.8
Q(ork elements to acti)-.11 E -.275(va)-.275 G(te b).275 E
(uilt-in GRA functionality in netw)-.22 E(ork elements.)-.11 E(It)5.5 E
(speci\214es this protocol speci\214cally in the conte)97 619.8 Q
(xt of UDP as well as generally in the)-.165 E(conte)97 632.8 Q
(xt of prospecti)-.165 E .33 -.165(ve \()-.275 H
(reliable multicast\) transport protocols for IP).165 E(.)-1.221 E
(Speakman/V)72 769 Q 305.126(icisano [P)-.66 F(age 1])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E/F1 13/Times-Bold@0 SF -1.196(Ta)
239.126 85 S(ble of Contents)1.196 E/F2 10/Times-Roman@0 SF
(1. Introduction)97 123 Q F0 11(......................)3.56 G F2(3)11.5
E(2. De\214nitions)97 135 Q F0 11(......................)8.55 G F2(3)
11.5 E(3. Applicability)97 147 Q F0 11(......................).22 G F2
(3)11.5 E(4. Rationale)97 159 Q F0 11(.......................).92 G F2
(4)11.5 E(5. Functionality)97 171 Q F0 11(.....................)13.41 G
F2(5)11.5 E(5.1. Headers)107 183 Q F0 11(......................)2.74 G
F2(5)11.5 E(5.1.1. Header F)117 195 Q(ormat in the Conte)-.15 E
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117 207 Q(ormat in the Conte)-.15 E(xt of an RMT)-.15 E F0 11
(...........)3.18 G F2(7)11.5 E(5.1.3. Header Contents)117 219 Q F0 11
(..................)6.07 G F2(8)11.5 E(5.2. Procedures)107 231 Q F0 11
(.....................)4.82 G F2(9)11.5 E(5.2.1. Netw)117 243 Q
(ork Elements)-.1 E F0 11(.................)12.14 G F2(9)11.5 E
(5.2.2. End Systems)117 255 Q F0 11(...................)7.3 G F2(10)6.5
E(6. Constraints on GRA Function Speci\214cations)97 267 Q F0 11
(............)12.16 G F2(11)6.5 E(7. Security Considerations)97 279 Q F0
11(..................)12.17 G F2(13)6.5 E
(8. Requirements from other Building Blocks)97 291 Q F0 11
(.............)8.42 G F2(13)6.5 E(9. Codepoint Considerations)97 303 Q
F0 11(..................)3.83 G F2(13)6.5 E(10. IAN)97 315 Q 2.5(AC)-.35
G(onsiderations)-2.5 E F0 11(...................)2.11 G F2(13)6.5 E
(11. De\214nitions)97 327 Q F0 11(......................)3.55 G F2(13)
6.5 E(12. Expired Drafts)97 339 Q F0 11(.....................)2.6 G F2
(14)6.5 E F0(Speakman/V)72 769 Q 305.126(icisano [P)-.66 F(age 2])-.165
E EP
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534.2 Q(GRA Neighbours)72 547.2 Q F1(3.)72 573.2 Q F2 -.35(Ap)5.5 G
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ore GRA headers that may)72 706.8 Q
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(Speakman/V)72 769 Q 255.626(icisano Section)-.66 F 2.75(3. [P)2.75 F
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ugh shared state\) such that their joint action results in a single coh\
erent function.)72 111 Q(GRA pack)72 137 Q
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(according to the appropriate GRA function speci\214cation.)72 150 Q
(The GRA header is parsed to identify the session to which the pack)72
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(GRA function for that session, if an)72 189 Q 4.18 -.715(y. E)-.165 H
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(nd the intelligence of the operation of the session.)-2.75 E(The de\
\214nition of the GRA signalling protocol speci\214ed here is suf)72
647.6 Q(\214ciently general to be applied)-.275 E(to an)72 660.6 Q 2.75
(yp)-.165 G(rospecti)-2.75 E .33 -.165(ve U)-.275 H
(DP-based application protocol or an).165 E 2.75(yR)-.165 G
(MT for IP that is designed to mak)-2.75 E(e)-.11 E(use of GRA.)72 673.6
Q(Such a protocol may simply insert a GRA header in the transport heade\
r of some)5.5 E(subset of pack)72 686.6 Q
(ets in a session for those pack)-.11 E(ets to be processed by netw)-.11
E(ork-element-based GRA)-.11 E 2.75(functions. F)72 699.6 R
(or RMTs, GRA functionality is de\214ned entirely in terms of the netw)
-.165 E(ork layer header)-.11 E
(and the GRA header and so is completely transport-layer independent.)72
712.6 Q -.165(Fo)5.5 G 2.75(rU).165 G(DP applications,)-2.75 E
(GRA functionality is de\214ned entirely in terms of the netw)72 725.6 Q
(ork layer header)-.11 E 2.75(,t)-.44 G(he UDP header)-2.75 E 2.75(,a)
-.44 G(nd)-2.75 E(Speakman/V)72 769 Q 255.626(icisano Section)-.66 F
2.75(4. [P)2.75 F(age 4])-.165 E EP
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/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 79.523(-DRAFT Expires:)-1.012 F
(July 2003)2.75 E(January 2003)115.79 E
(the GRA header and so is completely application-layer independent.)72
85 Q(Netw)5.5 E(ork-element-based)-.11 E(GRA functionality can thus be \
applied with identical semantics across dif)72 98 Q
(ferent UDP applications)-.275 E(or RMTs.)72 111 Q(Gi)72 137 Q -.165(ve)
-.275 G 2.75(ni).165 G(ts netw)-2.75 E(ork-layer)-.11 E 2.75(,h)-.44 G(\
op-by-hop mechanics, the de\214nition of GRA signalling speci\214ed her\
e)-2.75 E(does not o)72 150 Q -.165(ve)-.165 G
(rlap with functionality pro).165 E(vided by an)-.165 E 2.75(yo)-.165 G
(ther reliable multicast b)-2.75 E(uilding block.)-.22 E/F1 11
/Times-Bold@0 SF(5.)72 189 Q/F2 14/Times-Bold@0 SF(Functionality)5.5 E
F0(The operation of the GRA signalling protocol is speci\214ed here in \
terms of the format of GRA)72 205.6 Q
(headers and procedures for processing those headers in netw)72 218.6 Q
(ork elements.)-.11 E(In the conte)72 244.6 Q
(xt of this document, the direct path is the path tak)-.165 E
(en by a pack)-.11 E(et from a source to a)-.11 E(recei)72 257.6 Q -.165
(ve)-.275 G 2.75(ra).165 G 2.75(sd)-2.75 G(etermined by IP routing.)
-2.75 E(The re)5.5 E -.165(ve)-.275 G(rse path is the path tak).165 E
(en by a pack)-.11 E(et from a)-.11 E(recei)72 270.6 Q -.165(ve)-.275 G
2.75(rt).165 G 2.75(oas)-2.75 G(ource as it is forw)-2.75 E
(arded through the sequence of upstream GRA neighbours)-.11 E
(between the recei)72 283.6 Q -.165(ve)-.275 G 2.75(ra).165 G
(nd the source.)-2.75 E(Direct GRA pack)5.5 E(ets are GRA pack)-.11 E
(ets being forw)-.11 E(arded by)-.11 E(IP routing on the direct path.)72
296.6 Q(Re)5.5 E -.165(ve)-.275 G(rse GRA pack).165 E(ets are GRA pack)
-.11 E(ets being forw)-.11 E(arded GRA-hop-)-.11 E(by-GRA-hop on the re)
72 309.6 Q -.165(ve)-.275 G(rse path.).165 E F1(5.1.)72 348.6 Q/F3 13
/Times-Bold@0 SF(Headers)5.5 E F0(The GRA header is best concei)72 365.2
Q -.165(ve)-.275 G 2.75(do).165 G 2.75(fa)-2.75 G 2.75(sa)-2.75 G
(ugmenting the transport header and must be a)-2.75 E -.275(va)-.22 G
(ilable at).275 E(an)72 378.2 Q 2.75(yl)-.165 G(ayer in the communicati\
ons stack at which the transport header \(the application header in the)
-2.75 E(case of UDP\) is also a)72 391.2 Q -.275(va)-.22 G(ilable.).275
E(GRA pack)72 417.2 Q(ets intended for interpretation in netw)-.11 E
(ork elements must bear a)-.11 E F1(netw)2.75 E(ork lay)-.11 E(er)-.11 E
(indication)72 430.2 Q F0(that the GRA header is present.)2.75 E 2.75
(An)5.5 G .55 -.275(ew I)-2.75 H 2.75(Po).275 G
(ption will be created speci\214cally to signal)-2.75 E
(the presence of the GRA header at the netw)72 443.2 Q(ork layer)-.11 E
(.)-.605 E(GRA headers may be used in pack)72 469.2 Q
(ets without this netw)-.11 E(ork layer indication for the purposes of)
-.11 E(purely end-to-end GRA-related e)72 482.2 Q
(xchanges within a session.)-.165 E(GRA pack)72 508.2 Q
(ets must also bear a)-.11 E F1(transport lay)2.75 E(er indication)-.11
E F0(that the GRA header is present since)2.75 E
(IP options are not typically a)72 521.2 Q -.275(va)-.22 G(ilable abo)
.275 E .33 -.165(ve t)-.165 H(he netw).165 E(ork layer)-.11 E 5.5(.T)
-.605 G(he method for detecting the)-5.5 E(presence of the GRA header a\
t the transport layer is based upon the G-bit \(de\214ned belo)72 534.2
Q(w\) being)-.275 E(set in the common portion of the GRA header which, \
when present, must immediately follo)72 547.2 Q 2.75(wt)-.275 G(he)-2.75
E(netw)72 560.2 Q(ork header)-.11 E(.)-.605 E F1(NO)97 576.8 Q 1.98 -.99
(TA B)-.44 H(ENE:).99 E F0 2.75(AU)2.75 G
(DP application or an RMT must specify its o)-2.75 E(wn application or)
-.275 E(transport headers, respecti)97 589.8 Q -.165(ve)-.275 G(ly).165
E 2.75(,s)-.715 G(uch that the v)-2.75 E
(alue of the bit in this same location in)-.275 E(their o)97 602.8 Q
(wn headers is al)-.275 E -.11(wa)-.11 G(ys zero.).11 E -.165(Fo)72
619.4 S 2.75(rU).165 G(DP)-2.75 E 2.75(,d)-1.221 G(irect GRA pack)-2.75
E(ets can be associated with a globally unique transport session based)
-.11 E(upon the IP address information and the UDP port information.)72
632.4 Q(Re)5.5 E -.165(ve)-.275 G(rse GRA pack).165 E(ets must also)-.11
E(be associated with the globally unique transport session to which the)
72 645.4 Q 2.75(yr)-.165 G(efer)-2.75 E 2.75(,a)-.44 G
(nd while, at least for)-2.75 E(UDP)72 658.4 Q 2.75(,p)-1.221 G
(ort information is typically a)-2.75 E -.275(va)-.22 G
(ilable in the transport header).275 E 2.75(,t)-.44 G
(he required IP address)-2.75 E(information is not a)72 671.4 Q -.275
(va)-.22 G(ilable from the IP header since it will be addressed to a GR\
A neighbour).275 E(.)-.605 E(Consequently)72 697.4 Q 2.75(,f)-.715 G
(or re)-2.75 E -.165(ve)-.275 G(rse GRA pack).165 E
(ets, this information must be recorded inside the GRA)-.11 E
(headers of re)72 710.4 Q -.165(ve)-.275 G(rse GRA pack).165 E
(ets to pro)-.11 E(vide unambiguous)-.165 E F1
(transport session identi\214cation)2.75 E F0 5.5(.S)C(ince)-5.5 E
(these IP address \214elds will only be present in re)72 723.4 Q -.165
(ve)-.275 G(rse GRA pack).165 E(ets, a)-.11 E F1(dir)2.75 E(ect/r)-.198
E -2.53 -.165(ev e)-.198 H(rse).165 E F0(Speakman/V)72 769 Q 247.376
(icisano Section)-.66 F 2.75(5.1. [P)2.75 F(age 5])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E/F1 11/Times-Bold@0 SF
(discriminator)72 85 Q F0(has been pro)2.75 E
(vided in the common portion of the GRA header)-.165 E 5.5(.T)-.605 G
(he same transport)-5.5 E
(session identi\214cation scheme applies to RMTs with the dif)72 98 Q
(ference that an NLA-scoped host)-.275 E(session identi\214er is carrie\
d directly in the GRA header in place of "borro)72 111 Q
(wing" port information)-.275 E(from the transport.)72 124 Q
(Note also that in re)72 150 Q -.165(ve)-.275 G(rse pack).165 E
(ets, the destination address is further required in case the re)-.11 E
-.165(ve)-.275 G(rse).165 E(GRA pack)72 163 Q
(et is to be subject to multicast forw)-.11 E
(arding as part of the corresponding GRA function)-.11 E
(de\214nition such as in the case of a suppression service.)72 176 Q
(The operand \214eld may be one of tw)72 202 Q 2.75(ot)-.11 G
(ypes: it may consist of a \214x)-2.75 E(ed number of \214x)-.165 E
(ed-format)-.165 E(operands, or a v)72 215 Q(ariable number of v)-.275 E
(ariable-format operands.)-.275 E(While v)5.5 E(ariable operands may)
-.275 E(pro)72 228 Q(vide a de)-.165 E(gree of feature \215e)-.165 E
(xibility)-.165 E 2.75(,t)-.715 G(he o)-2.75 E -.165(ve)-.165 G
(rhead associated with parsing v).165 E(ariable operand lists)-.275 E
(may tax the time constraints on forw)72 241 Q
(arding-time processing of GRA, so a)-.11 E F1(\214xed-)2.75 E
(operand/v)72 254 Q(ariable-operand discriminator)-.11 E F0
(has been pro)2.75 E(vided in the common portion of the GRA)-.165 E
(header so that netw)72 267 Q(ork elements can ef)-.11 E
(\214ciently detect more comple)-.275 E 2.75(xG)-.165 G
(RA headers and mak)-2.75 E 2.75(ea)-.11 G(n)-2.75 E
(early determination as to ho)72 280 Q 2.75(wt)-.275 G 2.75(oh)-2.75 G
(andle them.)-2.75 E(Speakman/V)72 769 Q 239.126(icisano Section)-.66 F
2.75(5.1.1. [P)2.75 F(age 6])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E/F1 11/Times-Bold@0 SF 2.75
(5.1.1. Header)72 85 R -.275(Fo)2.75 G(rmat in the Context of UDP).275 E
F0 2.75(AG)72 101.6 S(RA header in the conte)-2.75 E
(xt of UDP must be formatted as follo)-.165 E(ws:)-.275 E/F2 8/Courier@0
SF(IP HEADER including the IP GRA OPTION)86.4 127.6 Q(UDP HEADER)86.4
153.6 Q
(.................................................................)86.4
166.6 Q 48(.S)86.4 179.6 S(ource Port)-48 E 28.8(.D)48 G
(estination Port)-28.8 E(.)43.2 E
(.................................................................)86.4
192.6 Q 52.8(.C)86.4 205.6 S(heck Sum)-52.8 E 43.2(.T)52.8 G(PDU Length)
-43.2 E(.)52.8 E
(.................................................................)86.4
218.6 Q(The common portion of the GRA header:)86.4 244.6 Q 91.2(0123)
91.2 257.6 S 4.8(01234567890123456789012345678901)91.2 270.6 S
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+)86.4
283.6 Q(|G|R|V|-|-|-|V N| Header Length |)86.4 296.6 Q(Function ID)9.6 E
4.8(|I)14.4 G(nstance #)-4.8 E(|)14.4 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+)86.4
309.6 Q(... followed immediately, in reverse GRA packets only,)86.4
335.6 Q(by transport-session-identifying IP address information:)105.6
348.6 Q
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
361.6 Q 57.6(|N)86.4 374.6 S(etwork Layer Source \(IP\) Address)-57.6 E
(... |)67.2 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
387.6 Q 19.2(|N)86.4 400.6 S
(etwork Layer Destination \(IP Multicast Group\) Address ... |)-19.2 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
413.6 Q
(... followed immediately by the GRA-function-specific operand portion)
86.4 439.6 Q(of the GRA header:)105.6 452.6 Q
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
465.6 Q 120(|O)86.4 478.6 S 120(perands ...)-120 F(|)4.8 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
491.6 Q(... followed immediately by the APDU.)86.4 517.6 Q/F3 10
/Times-Roman@0 SF(Figure 1 - GRA Header F)178.995 543.6 Q
(ormat in the Conte)-.15 E(xt of UDP)-.15 E F0(Speakman/V)72 769 Q
239.126(icisano Section)-.66 F 2.75(5.1.2. [P)2.75 F(age 7])-.165 E EP
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/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 79.523(-DRAFT Expires:)-1.012 F
(July 2003)2.75 E(January 2003)115.79 E/F1 11/Times-Bold@0 SF 2.75
(5.1.2. Header)72 85 R -.275(Fo)2.75 G(rmat in the Context of an RMT)
.275 E F0 2.75(AG)72 101.6 S(RA header in the conte)-2.75 E
(xt of an RMT must be formatted as follo)-.165 E(ws:)-.275 E/F2 8
/Courier@0 SF(IP HEADER including the IP GRA OPTION)86.4 127.6 Q
(The common portion of the GRA header:)86.4 153.6 Q 91.2(0123)91.2 166.6
S 4.8(01234567890123456789012345678901)91.2 179.6 S
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+)86.4
192.6 Q 57.6(|N)86.4 205.6 S(LA-scoped host session identifier\(s\))
-57.6 E(|)67.2 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+)86.4
218.6 Q(|G|R|V|-|-|-|V N| Header Length |)86.4 231.6 Q(Function ID)9.6 E
4.8(|I)14.4 G(nstance #)-4.8 E(|)14.4 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+)86.4
244.6 Q(... followed immediately, in reverse GRA packets only,)86.4
270.6 Q(by transport-session-identifying IP address information:)105.6
283.6 Q
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
296.6 Q 57.6(|N)86.4 309.6 S(etwork Layer Source \(IP\) Address)-57.6 E
(... |)67.2 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
322.6 Q 19.2(|N)86.4 335.6 S
(etwork Layer Destination \(IP Multicast Group\) Address ... |)-19.2 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
348.6 Q
(... followed immediately by the GRA-function-specific operand portion)
86.4 374.6 Q(of the GRA header:)105.6 387.6 Q
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
400.6 Q 120(|O)86.4 413.6 S 120(perands ...)-120 F(|)4.8 E
(+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+)86.4
426.6 Q(... followed immediately by the TPDU.)86.4 452.6 Q/F3 10
/Times-Roman@0 SF(Figure 2 - GRA Header F)172.19 478.6 Q
(ormat in the Conte)-.15 E(xt of an RMT)-.15 E F1 2.75(5.1.3. Header)72
517.6 R(Contents)2.75 E/F4 11/Courier@0 SF
(NLA-Scoped Host Session Identifier \(HSI\))72 534.2 Q F0 -.165(Fo)88.5
547.2 S 2.75(rR).165 G(MTs, the logical equi)-2.75 E -.275(va)-.275 G
(lent of the UDP source and destination ports.).275 E F4(G-bit)72 563.8
Q F0(MUST be set.)88.5 576.8 Q(Signals the presence of a prepended)5.5 E
F1(G)2.75 E F0(RA header to UDP applications)A -.165(ex)88.5 589.8 S
(pecting APDUs after the UDP header or to RMTs e).165 E
(xpecting TPDUs after the IP header)-.165 E(.)-.605 E F4(R-bit)72 606.4
Q F0(Clear on direct GRA pack)88.5 619.4 Q(ets, set on)-.11 E F1(R)2.75
E F0 -2.365 -.275(ev e)D(rse GRA pack).275 E(ets.)-.11 E F4(V-bit)72 636
Q F0(Clear on \214x)88.5 649 Q(ed-operand GRA pack)-.165 E(et, set on)
-.11 E F1(V)2.75 E F0(ariable-operand GRA pack)A(ets.)-.11 E F4(VN-bits)
72 665.6 Q F0(GRA)88.5 678.6 Q F1(V)2.75 E F0(ersion)A F1(N)2.75 E F0
(umber)A 2.75(,0)-.44 G(x0 in this instance.)-2.75 E F4(Header Length)72
695.2 Q F0 -.88(To)88.5 708.2 S(tal length of the GRA header in longw)
.88 E(ords.)-.11 E(Speakman/V)72 769 Q 239.126(icisano Section)-.66 F
2.75(5.1.3. [P)2.75 F(age 8])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E/F1 11/Courier@0 SF
(Function ID \(GFID\))72 85 Q F0(The GFID is the name of the transport-\
session-speci\214c instance of the GRA function to be)88.5 98 Q
(used to process the GRA header)88.5 111 Q(.)-.605 E F1
(GFID Instance Number \(GFIN\))72 127.6 Q F0(The GFIN is the session-sp\
eci\214c instance number of the GRA function to be used to process)88.5
140.6 Q(the GRA header)88.5 153.6 Q(.)-.605 E F1(Source IP Address)72
170.2 Q(Destination IP \(Multicast Group\) Address)72 186.8 Q F0(Re)88.5
199.8 Q -.165(ve)-.275 G(rse GRA pack).165 E(ets must bear the netw)-.11
E(ork-layer addresses of the source and destination for)-.11 E(the iden\
ti\214cation of the transport session within which the GRA pack)88.5
212.8 Q(ets are to be processed.)-.11 E(Note that while these addresses\
 are rendered here as IPv4 addresses, their actual format in the)88.5
238.8 Q(conte)88.5 251.8 Q(xt of UDP or a gi)-.165 E -.165(ve)-.275 G
2.75(nR).165 G(MT is determined by the netw)-2.75 E
(ork layer protocol in which UDP or)-.11 E(the RMT is operating.)88.5
264.8 Q F1(Operands)72 294.4 Q F0
(The operands \(including a GSID; see belo)88.5 307.4 Q
(w\) as de\214ned for one of the GRA services in the)-.275 E
(GRA function speci\214cation for the gi)88.5 320.4 Q -.165(ve)-.275 G
2.75(nG).165 G(FID.)-2.75 E/F2 11/Times-Bold@0 SF(5.2.)72 359.4 Q/F3 13
/Times-Bold@0 SF(Pr)5.5 E(ocedur)-.234 E(es)-.234 E F2 2.75(5.2.1. Netw)
72 389 R(ork Elements)-.11 E F0(Netw)72 405.6 Q(ork elements that e)-.11
E(xplicitly detect the IP GRA option \(TBD\) in a pack)-.165 E
(et must then locate)-.11 E
(and parse the GRA header \214rst to determine the pack)72 418.6 Q(et')
-.11 E 2.75(sa)-.605 G(dmissibility and second to determine its)-2.75 E
2.75(handling. The)72 431.6 R(GRA header is al)2.75 E -.11(wa)-.11 G
(ys located directly follo).11 E(wing the netw)-.275 E(ork header)-.11 E
2.75(,b)-.44 G(ut netw)-2.97 E(ork)-.11 E(elements must mak)72 444.6 Q
2.75(eat)-.11 G(ransport-protocol-speci\214c determination of its forma\
t which will be as)-2.75 E(speci\214ed in Figure 1 for UDP and as speci\
\214ed in Figure 2 for all other transport protocols.)72 457.6 Q F2(NO)
97 474.2 Q 1.98 -.99(TA B)-.44 H(ENE:).99 E F0(There')2.75 E 2.75(sas)
-.605 G(trong assumption here that netw)-2.75 E
(ork elements do IP option)-.11 E(detection BEFORE the)97 487.2 Q 2.75
(ym)-.165 G(ak)-2.75 E 2.75(ea)-.11 G .33 -.165(ny d)-2.75 H
(eterminations based on the destination netw).165 E(ork)-.11 E
(layer address in the general forw)97 500.2 Q(arding path.)-.11 E
(If the G-bit is not set, the netw)72 516.8 Q
(ork element must discard the pack)-.11 E(et.)-.11 E(If the pack)72
542.8 Q(et is a re)-.11 E -.165(ve)-.275 G(rse GRA unicast pack).165 E
(et, the netw)-.11 E(ork element must determine whether the)-.11 E(pack)
72 555.8 Q(et bears a destination address addressing the netw)-.11 E
(ork element itself.)-.11 E(If a re)5.5 E -.165(ve)-.275 G(rse GRA).165
E(unicast pack)72 568.8 Q(et is not addressed to the netw)-.11 E
(ork element itself, it must continue to be processed just)-.11 E
(as if the IP GRA option had NO)72 581.8 Q 2.75(Tb)-.44 G(een detected.)
-2.75 E(If a re)72 607.8 Q -.165(ve)-.275 G(rse GRA unicast pack).165 E
(et is addressed to the netw)-.11 E(ork element itself, the netw)-.11 E
(ork element)-.11 E
(must \214rst correct for potential unicast routing asymmetries.)72
620.8 Q(In particular)5.5 E 2.75(,s)-.44 G(ince a re)-2.75 E -.165(ve)
-.275 G(rse GRA).165 E(unicast pack)72 633.8 Q(et may tra)-.11 E -.165
(ve)-.22 G(rse a non-contiguous GRA hop and therefore arri).165 E .33
-.165(ve a)-.275 H 2.75(tt).165 G(he upstream GRA)-2.75 E
(neighbour on other than the interf)72 646.8 Q(ace to which it w)-.11 E
(as addressed, the pack)-.11 E(et must, upon receipt, be)-.11 E
(reassociated by the netw)72 659.8 Q(ork element with the interf)-.11 E
(ace to which it w)-.11 E(as addressed.)-.11 E(Note that the)5.5 E
(destination address check is essential since re)72 672.8 Q -.165(ve)
-.275 G(rse pack).165 E(ets are seen not just by the GRA)-.11 E
(neighbour to which the)72 685.8 Q 2.75(ya)-.165 G(re unicast b)-2.75 E
(ut by an)-.22 E 2.75(yi)-.165 G(nterv)-2.75 E
(ening GRA capable routers as well \(due to)-.165 E
(the IP GRA option\).)72 698.8 Q(Netw)72 724.8 Q
(ork elements must then v)-.11 E(erify that the)-.165 E 2.75(yh)-.165 G
-2.475 -.22(av e)-2.75 H(corresponding de\214nitions for the v)2.97 E
(ersion)-.165 E(Speakman/V)72 769 Q 239.126(icisano Section)-.66 F 2.75
(5.2.1. [P)2.75 F(age 9])-.165 E EP
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/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 79.523(-DRAFT Expires:)-1.012 F
(July 2003)2.75 E(January 2003)115.79 E(number and the GFID.)72 85 Q
-.165(Pa)5.5 G(ck).165 E(ets that f)-.11 E(ail this v)-.11 E
(eri\214cation must continue to be processed just as if)-.165 E
(the IP GRA option had NO)72 98 Q 2.75(Tb)-.44 G(een detected.)-2.75 E(\
Admissibility is further determined by matching the source and destinat\
ion addresses \(found in)72 124 Q
(the IP header in the case of direct GRA pack)72 137 Q
(ets and inside the GRA header in the case of re)-.11 E -.165(ve)-.275 G
(rse).165 E(GRA pack)72 150 Q
(ets\), and the GFID \(and possibly the incoming interf)-.11 E(ace\) ag)
-.11 E(ainst an)-.055 E 2.75(yl)-.165 G(ocal access lists)-2.75 E
(protecting access to GRA functionality)72 163 Q 5.5(.P)-.715 G(ack)
-5.665 E(ets block)-.11 E(ed by such lists must continue to be)-.11 E
(processed just as if the IP GRA option had NO)72 176 Q 2.75(Tb)-.44 G
(een detected.)-2.75 E -.165(Fo)72 202 S 2.75(rp).165 G(ack)-2.75 E(ets\
 passed by such lists, the GRA function corresponding to the GFID must \
be in)-.11 E -.22(vo)-.44 G -.11(ke).22 G(d).11 E(and passed the pack)72
215 Q(et itself as well as the identity of the incoming interf)-.11 E
(ace.)-.11 E(The netw)72 241 Q(ork element may mak)-.11 E 2.75(el)-.11 G
(ocal determinations on the processing priority of such GRA)-2.75 E
(pack)72 254 Q(ets based on an)-.11 E 2.75(yl)-.165 G
(ocal conditions or an)-2.75 E 2.75(ya)-.165 G(ttrib)-2.75 E
(utes of the GRA pack)-.22 E(et itself.)-.11 E(More)5.5 E
(speci\214cally)72 267 Q 2.75(,an)-.715 G(etw)-2.75 E
(ork element is not constrained to order GRA pack)-.11 E(ets relati)-.11
E .33 -.165(ve t)-.275 H 2.75(on).165 G(on-GRA)-2.75 E(pack)72 280 Q
(ets in an)-.11 E 2.75(yw)-.165 G(ay)-2.86 E 5.5(.N)-.715 G(etw)-5.5 E
(ork elements must, ho)-.11 E(we)-.275 E -.165(ve)-.275 G .88 -.44(r, p)
.165 H(rocess admissible GRA pack).44 E(ets matching)-.11 E 2.75(ap)72
293 S(articular \(transport-session-scoped\) GFID in relati)-2.75 E .33
-.165(ve o)-.275 H(rder).165 E(.)-.605 E
(All further processing of a GRA pack)72 319 Q
(et is GRA-function-speci\214c as de\214ned by the GRA function)-.11 E
(speci\214cation for the GFID.)72 332 Q(In particular)5.5 E 2.75(,i)-.44
G 2.75(ti)-2.75 G 2.75(si)-2.75 G
(ncumbent upon the GRA function to determine the)-2.75 E(ultimate f)72
345 Q(ate of the pack)-.11 E(et itself.)-.11 E(Netw)72 371 Q
(ork elements must pro)-.11 E(vide a multicast forw)-.165 E
(arding service which permits selecti)-.11 E -.165(ve)-.275 G(forw)72
384 Q(arding on a speci\214ed subset of the interf)-.11 E
(aces on a multicast route.)-.11 E/F1 11/Times-Bold@0 SF 2.75
(5.2.2. End)72 423 R(Systems)2.75 E F0(End systems are de\214ned for th\
e purposes of this section as either host-resident UDP applications)72
439.6 Q(or RMT stacks.)72 452.6 Q(End systems originating GRA pack)72
469.2 Q(ets must format them as speci\214ed in Figure 1 for UDP)-.11 E(\
applications and as speci\214ed in Figure 2 for all other transport pro\
tocols.)72 482.2 Q(The underlying netw)5.5 E(ork)-.11 E
(layers of these end systems must pro)72 495.2 Q
(vide the ability to selecti)-.165 E -.165(ve)-.275 G
(ly add the IP GRA option to GRA).165 E(pack)72 508.2 Q
(ets submitted for transmission by these end systems.)-.11 E
(Upon receipt, end systems must e)72 534.2 Q
(xplicitly detect the presence of a GRA header in a pack)-.165 E
(et based)-.11 E(on the state of the G-bit and must then locate and par\
se the GRA header \214rst to determine the)72 547.2 Q(pack)72 560.2 Q
(et')-.11 E 2.75(sa)-.605 G
(dmissibility and second to determine its handling.)-2.75 E
(Note that the location of the G-bit)5.5 E
(depends on whether the end system is a UDP application or an RMT)72
573.2 Q(.)-.814 E(End systems must then v)72 599.2 Q(erify that the)
-.165 E 2.75(yh)-.165 G -2.475 -.22(av e)-2.75 H
(corresponding de\214nitions for the v)2.97 E(ersion number and)-.165 E
(the GFID.)72 612.2 Q -.165(Pa)5.5 G(ck).165 E(ets that f)-.11 E
(ail this v)-.11 E
(eri\214cation must continue to be processed ignoring the GRA)-.165 E
(header altogether)72 625.2 Q(.)-.605 E
(All further processing of a GRA pack)72 651.2 Q
(et is GRA-function-speci\214c as de\214ned by the GRA function)-.11 E
(speci\214cation for the GFID.)72 664.2 Q(Speakman/V)72 769 Q 233.626
(icisano Section)-.66 F 2.75(5.2.2. [P)2.75 F(age 10])-.165 E EP
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/F0 11/Times-Roman@0 SF(INTERNET)72 49 Q 79.523(-DRAFT Expires:)-1.012 F
(July 2003)2.75 E(January 2003)115.79 E/F1 11/Times-Bold@0 SF(6.)72 85 Q
/F2 14/Times-Bold@0 SF(Constraints on GRA Function Speci\214cations)5.5
E F0(General constraints on GRA function speci\214cations are described\
 here since those constraints)72 101.6 Q
(stem primarily from consideration of the processing en)72 114.6 Q
(vironment in the forw)-.44 E(arding path of a)-.11 E(netw)72 127.6 Q
(ork element.)-.11 E(Indi)5.5 E(vidual GRA function speci\214cations mu\
st adhere to the constraints stated)-.275 E
(here, and these constraints may be e)72 140.6 Q(xpanded in light of an)
-.165 E 2.75(yi)-.165 G(rrational e)-2.75 E(xuberance detected in)-.165
E(GRA function speci\214cations themselv)72 153.6 Q(es.)-.165 E F1
(Static and dynamic GRA functions)72 183.2 Q F0(The lo)72 196.2 Q
(wer half of the GFID space is reserv)-.275 E(ed for static, well-kno)
-.165 E(wn GRA function speci\214cations.)-.275 E
(The upper half of the GFID space is reserv)72 209.2 Q
(ed for dynamic, proprietary GRA function)-.165 E(speci\214cations when\
 it becomes possible to de\214ne these through a GRA control protocol.)
72 222.2 Q(Thus)5.5 E
(the upper half of the GFID space is scoped by the transport session.)72
235.2 Q F1(Maximum number of GRA ser)72 264.8 Q(vices)-.11 E F0(No more\
 than 8 GRA services may be de\214ned for a single GRA function.)72
277.8 Q(The de\214nition of the)5.5 E(GRA service identi\214er \(GSID\)\
 is a matter purely local to the GRA function speci\214cation e)72 290.8
Q(xcept)-.165 E(to say that GSIDs must be encoded in the operand portio\
n of the GRA header)72 303.8 Q(.)-.605 E F1(GRA neighbour disco)72 333.4
Q -.11(ve)-.11 G(ry ser).11 E(vice)-.11 E F0
(If a GRA function speci\214es a GRA service for re)72 346.4 Q -.165(ve)
-.275 G(rse pack).165 E(ets, it must also specify a GRA)-.11 E
(service for GRA neighbour disco)72 359.4 Q -.165(ve)-.165 G
(ry in the session.).165 E(Such a GRA service may also be used as a)5.5
E(general session information service to pro)72 372.4 Q(vide an)-.165 E
2.75(yo)-.165 G(ther session-speci\214c parameters required by)-2.75 E
(the GRA function.)72 385.4 Q F1 -.11(Pa)72 415 S(ck).11 E(et Access)
-.11 E F0(The GRA header MUST be self-contained.)72 428 Q
(That is, all parameters required by a gi)5.5 E -.165(ve)-.275 G 2.75
(nG).165 G(RA)-2.75 E(service MUST be pro)72 441 Q
(vided in the GRA header itself other than those pro)-.165 E
(vided in the netw)-.165 E(ork)-.11 E
(header \(the UDP header in the case of UDP applications\).)72 454 Q
(More speci\214cally)5.5 E 2.75(,t)-.715 G(here is no)-2.75 E
(capability de\214ned for GRA to specify operands by of)72 467 Q
(fset into the pack)-.275 E 2.75(et. This)-.11 F(may necessitate)2.75 E
(duplicating information carried else)72 480 Q(where in the pack)-.275 E
2.75(et. Note)-.11 F(that when a GRA header is present,)2.75 E
(an RMT is free to refer to the GRA header for v)72 493 Q
(alues that normally w)-.275 E(ould be carried else)-.11 E(where in)
-.275 E(the transport header \()72 506 Q F1(e.g)A(.)-.165 E F0
(the HSI\).)5.5 E F1 -.11(Pa)72 535.6 S(ck).11 E(et Modi\214cation)-.11
E F0 2.75(AG)72 548.6 S(RA pack)-2.75 E(et may not be modi\214ed in an)
-.11 E 2.75(yw)-.165 G(ay by a netw)-2.86 E
(ork element other than to write to the)-.11 E
(GRA header and then only in the same format in which the header w)72
561.6 Q(as recei)-.11 E -.165(ve)-.275 G 2.75(d. GRA).165 F(speci\214es)
2.75 E(no pack)72 574.6 Q(et encapsulation or pack)-.11 E
(et decapsulation capabilities.)-.11 E(In addition, this constraint)5.5
E(precludes pack)72 587.6 Q(et accumulation.)-.11 E F1 -.11(Pa)72 617.2
S(ck).11 E(et Generation)-.11 E F0
(GRA Function speci\214cations may specify the generation and forw)72
630.2 Q(arding of a pack)-.11 E(et consisting)-.11 E(only of a GRA head\
er de\214ned by the GRA function speci\214cation and deri)72 643.2 Q
-.165(ve)-.275 G 2.75(df).165 G(rom the cop)-2.75 E 2.75(yo)-.11 G 2.75
(fa)-2.75 G(recei)72 656.2 Q -.165(ve)-.275 G 2.75(dG).165 G(RA header)
-2.75 E 5.5(.T)-.605 G(hese pack)-5.5 E
(ets may be used for delayed or periodic GRA-related e)-.11 E -.165(ve)
-.275 G(nts in).165 E(the session.)72 669.2 Q F1(Fixed and V)72 698.8 Q
(ariable Operands)-1.012 E F0
(An implementation of GRA must support GRA headers with either a \214x)
72 711.8 Q(ed number of operands in)-.165 E<8c78>72 724.8 Q
(ed formats, or a v)-.165 E(ariable number of operands in v)-.275 E
(ariable formats.)-.275 E(Fix)5.5 E(ed format GRA headers)-.165 E
(Speakman/V)72 769 Q 250.126(icisano Section)-.66 F 2.75(6. [P)2.75 F
(age 11])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E
(should be used in GRA service speci\214cations where forw)72 85 Q
(arding-time processing performance is)-.11 E(the priority)72 98 Q 5.5
(.V)-.715 G(ariable format GRA headers should be used in GRA service sp\
eci\214cations where)-6.721 E(syntactic \215e)72 111 Q
(xibility is the priority)-.165 E 5.5(.V)-.715 G
(ariable format GRA headers must be self-describing to the)-6.721 E
-.165(ex)72 124 S(tent that the type, length, and v).165 E
(alue of all operands can be determined dynamically)-.275 E 5.5(.W)-.715
G(hile)-5.5 E -.275(va)72 137 S(riable-format operands may v).275 E
(ary across GRA pack)-.275 E(ets, the)-.11 E 2.75(ym)-.165 G(ay not v)
-2.75 E(ary from the format)-.275 E(established for a gi)72 150 Q -.165
(ve)-.275 G 2.75(np).165 G(ack)-2.75 E(et by its originator)-.11 E(.)
-.605 E/F1 11/Times-Bold@0 SF(Operands Semantics)72 179.6 Q F0(While op\
erands may represent a whole range of meaningful \(to the transport\) a\
ttrib)72 192.6 Q(utes, the)-.22 E 2.75(ya)-.165 G(re)-2.75 E
(not interpreted by GRA in other than the conte)72 205.6 Q
(xt of the operators of each type supported by GRA.)-.165 E(That is, th\
e numerical and relational operators treat operands as unsigned inte)72
218.6 Q(gers, and the logical)-.165 E
(operators treat operands as bit \214elds \()72 231.6 Q F1(e.g)A(.)-.165
E F0(for the purposes of aggre)2.75 E -.055(ga)-.165 G(tion\).).055 E F1
(Designated KEY Operand)72 261.2 Q F0 2.75(AG)72 274.2 S(RA function sp\
eci\214cation may de\214ne a single distinguished operand, up to 32 bit\
s in length,)-2.75 E(to be a k)72 287.2 Q .33 -.165(ey f)-.11 H
(or the purposes of inde).165 E(xing sub-service-speci\214c state.)-.165
E F1(GRA Function State)72 316.8 Q F0 2.75(AG)72 329.8 S
(RA function speci\214cation may specify up to 8 GRA-function-local v)
-2.75 E(ariables, 8 GRA-)-.275 E(function-local timers, and 1 interf)72
342.8 Q(ace list \(where an interf)-.11 E
(ace list may record no more interf)-.11 E(aces)-.11 E(than are recorde\
d on the multicast route corresponding to the session\).)72 355.8 Q F1
(GRA Ser)72 385.4 Q(vice State)-.11 E F0 -.165(Fo)72 398.4 S 2.75(re)
.165 G(ach GRA service, a GRA function speci\214cation may specify up t\
o 8 GRA-service-local)-2.75 E -.275(va)72 411.4 S
(riables, 8 GRA-service-local timers, storage for 1 full cop).275 E 2.75
(yo)-.11 G 2.75(ft)-2.75 G(he GRA header de\214ned by the)-2.75 E
(GRA service, and 1 GRA-service-local interf)72 424.4 Q(ace list.)-.11 E
(GRA header copies are intended for such)5.5 E
(functions as delayed forw)72 437.4 Q(arding and elimination.)-.11 E F1
-.275(Ke)72 467 S -.11(ye).275 G 2.75(dG).11 G(RA Ser)-2.75 E
(vice State)-.11 E F0 -.165(Fo)72 480 S 2.75(re).165 G
(ach instance of a k)-2.75 E -.165(ey)-.11 G 2.75(,aG)-.55 G
(RA service speci\214cation may specify up to 8 sub-service-local)-2.75
E -.275(va)72 493 S
(riables, 8 sub-service-local timers, storage for 1 full cop).275 E 2.75
(yo)-.11 G 2.75(ft)-2.75 G(he GRA header de\214ned by the)-2.75 E
(GRA service, and 1 sub-service-local interf)72 506 Q(ace list.)-.11 E
F1 -.275(Fo)72 535.6 S(rwarding Functions).275 E F0 2.75(AG)72 548.6 S
(RA service speci\214cation may specify unicast and or multicast forw)
-2.75 E(arding for a recei)-.11 E -.165(ve)-.275 G 2.75(dG).165 G(RA)
-2.75 E(pack)72 561.6 Q(et or for a GRA pack)-.11 E
(et generated by the GRA service and consisting only of the GRA header)
-.11 E(de\214ned by the GRA service.)72 574.6 Q(Unicast forw)5.5 E
(arding may be to an arbitrary unicast destination.)-.11 E
(Multicast forw)72 587.6 Q(arding may only be to the multicast group co\
rresponding to the multicast)-.11 E(distrib)72 600.6 Q
(ution tree for the session possibly augmented by an interf)-.22 E
(ace list for the purposes of)-.11 E(selecti)72 613.6 Q .33 -.165(ve f)
-.275 H(orw).165 E(arding.)-.11 E F1(Band)72 643.2 Q(width)-.165 E F0
(GRA is not intended for use on data pack)72 656.2 Q(ets in)-.11 E -.22
(vo)-.44 G(lv).22 E(ed in a transport')-.165 E 2.75(sb)-.605 G
(asic data con)-2.75 E -.165(vey)-.44 G(ance).165 E 2.75
(function. Rather)72 669.2 R 2.75(,i)-.44 G 2.75(ti)-2.75 G 2.75(si)
-2.75 G(ntended for control and e)-2.75 E
(xception processing within a session.)-.165 E(Neither the)5.5 E
(frequenc)72 682.2 Q 2.75(yo)-.165 G 2.75(fG)-2.75 G(RA pack)-2.75 E(et\
s nor their total data rate within a session may be more than 5% in the)
-.11 E(steady state.)72 695.2 Q(Speakman/V)72 769 Q 250.126
(icisano Section)-.66 F 2.75(6. [P)2.75 F(age 12])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E/F1 11/Times-Bold@0 SF(7.)72 85 Q
/F2 14/Times-Bold@0 SF(Security Considerations)5.5 E F0(Until a GRA con\
trol protocol can be de\214ned to securely con\214gure and manage acces\
s to GRA)72 101.6 Q(functionality in netw)72 114.6 Q(ork elements, netw)
-.11 E(ork elements must restrict access to GRA functionality)-.11 E
(through positi)72 127.6 Q .33 -.165(ve a)-.275 H(ccess lists e).165 E
(xplicitly con\214gured to permit access by the source/destination/GFID)
-.165 E(triplet \(and possibly by interf)72 140.6 Q
(ace as well\) where these addresses are found in the IP header in the)
-.11 E(case of direct GRA pack)72 153.6 Q
(ets and inside the GRA header in the case of re)-.11 E -.165(ve)-.275 G
(rse GRA pack).165 E(ets.)-.11 E(When and where a)72 179.6 Q -.275(va)
-.22 G(ilable, GRA will rely on general mechanisms for recei).275 E
-.165(ve)-.275 G 2.75(ra).165 G(ccess control and)-2.75 E
(for source and recei)72 192.6 Q -.165(ve)-.275 G 2.75(ra).165 G
(uthentication rather than mandating its o)-2.75 E(wn.)-.275 E F1(8.)72
244.6 Q F2(Requir)5.5 E(ements fr)-.252 E(om other Building Blocks)-.252
E F0(The only aspect of GRA functionality not completely de\214ned by G\
RA function speci\214cations is)72 261.2 Q
(the number of separate instances of the application of a gi)72 274.2 Q
-.165(ve)-.275 G 2.75(nG).165 G(RA function within a session as)-2.75 E
(represented by the GFIN.)72 287.2 Q(The e)5.5 E
(xpectation is that only one instance is typically required.)-.165 E
(In an)5.5 E(y)-.165 E(case, a UDP application or an RMT must not speci\
fy the use of more than 8 instances of a gi)72 300.2 Q -.165(ve)-.275 G
(n).165 E(GFID.)72 313.2 Q F1(9.)72 352.2 Q F2(Codepoint Considerations)
5.5 E F0(\(This section is in compliance with RFC3269\))72 368.8 Q F1
(10.)72 407.8 Q F2(IAN)5.5 E 3.5(AC)-.28 G(onsiderations)-3.5 E F0
(As part of de\214ning the ne)72 424.4 Q 2.75(wI)-.275 G 2.75(PG)-2.75 G
(RA option, an ne)-2.75 E 2.75(wI)-.275 G 2.75(Po)-2.75 G
(ption type will be requested from IAN)-2.75 E(A.)-.385 E
(It is further proposed here that the GFID name space be under IAN)72
450.4 Q 2.75(Aa)-.385 G(dministration.)-2.75 E F1(11.)72 489.4 Q F2
(De\214nitions)5.5 E F0
(The de\214nitions in this section apply throughout this document.)72
506 Q F1(Distrib)72 535.6 Q(ution T)-.22 E -.198(re)-.814 G(e).198 E F0
(The multicast distrib)88.5 548.6 Q(ution tree of netw)-.22 E
(ork elements de\214ned by netw)-.11 E(ork-layer multicast)-.11 E
(routing information for a gi)88.5 561.6 Q -.165(ve)-.275 G 2.75(nm).165
G(ulticast transport session rooted at a single root netw)-2.75 E(ork)
-.11 E(element \(at the host that is the source of the data in the tran\
sport session\), and f)88.5 574.6 Q(anning out)-.11 E
(\(possibly through transit netw)88.5 587.6 Q
(ork elements\) to one or more leaf netw)-.11 E
(ork elements \(at the hosts)-.11 E(that are the recei)88.5 600.6 Q
-.165(ve)-.275 G(rs of the data in the transport session\).).165 E F1
(Do)72 630.2 Q(wnstr)-.11 E(eam)-.198 E F0(In the direction a)88.5 643.2
Q -.11(wa)-.165 G 2.75(yf).11 G(rom the source and to)-2.75 E -.11(wa)
-.275 G(rd recei).11 E -.165(ve)-.275 G(rs.).165 E F1(Upstr)72 672.8 Q
(eam)-.198 E F0(In the direction a)88.5 685.8 Q -.11(wa)-.165 G 2.75(yf)
.11 G(rom recei)-2.75 E -.165(ve)-.275 G(rs and to).165 E -.11(wa)-.275
G(rd the source.).11 E(Speakman/V)72 769 Q 244.626(icisano Section)-.66
F 2.75(11. [P)2.75 F(age 13])-.165 E EP
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(July 2003)2.75 E(January 2003)115.79 E/F1 11/Times-Bold@0 SF(GRA pack)
72 85 Q(et)-.11 E F0 2.75(Ap)88.5 98 S(ack)-2.75 E
(et bearing a GRA header)-.11 E(.)-.605 E F1(GRA hop)72 127.6 Q F0
(The single logical hop between an)88.5 140.6 Q 2.75(yt)-.165 G .22 -.11
(wo G)-2.75 H(RA-capable netw).11 E
(ork elements adjacent \(in a strictly)-.11 E(upstream/do)88.5 153.6 Q
(wnstream sense\) to each other in the distrib)-.275 E(ution tree \()
-.22 E/F2 11/Times-Italic@0 SF(i.e)A(.)-.165 E F0 2.75(,n)C
(ot separated in the)-2.75 E(distrib)88.5 166.6 Q(ution tree by an)-.22
E 2.75(yo)-.165 G(ther GRA-capable netw)-2.75 E(ork element\).)-.11 E F1
(GRA Neighbours)72 196.2 Q F0 -1.1 -.88(Tw o)88.5 209.2 T
(GRA-capable netw)3.63 E(ork elements separated by a single GRA hop.)
-.11 E F1(Dir)72 238.8 Q(ect P)-.198 E(ath)-.11 E F0(The path tak)88.5
251.8 Q(en by a pack)-.11 E(et from a source to a recei)-.11 E -.165(ve)
-.275 G 2.75(ra).165 G 2.75(sd)-2.75 G(etermined by IP routing)-2.75 E
F1(Re)72 281.4 Q -.11(ve)-.165 G(rse P).11 E(ath)-.11 E F0(The path tak)
88.5 294.4 Q(en by a pack)-.11 E(et from a recei)-.11 E -.165(ve)-.275 G
2.75(rt).165 G 2.75(oas)-2.75 G(ource as it is forw)-2.75 E
(arded through the sequence)-.11 E
(of upstream GRA neighbours between the recei)88.5 307.4 Q -.165(ve)
-.275 G 2.75(ra).165 G(nd the source.)-2.75 E F1(Dir)72 337 Q(ect GRA P)
-.198 E(ack)-.11 E(ets)-.11 E F0(GRA pack)88.5 350 Q(ets being forw)-.11
E(arded by IP routing on the direct path.)-.11 E F1(Re)72 379.6 Q -.11
(ve)-.165 G(rse GRA P).11 E(ack)-.11 E(ets)-.11 E F0(GRA pack)88.5 392.6
Q(ets being forw)-.11 E(arded GRA-hop-by-GRA-hop on the re)-.11 E -.165
(ve)-.275 G(rse path.).165 E F1(Suppr)72 422.2 Q(ession)-.198 E F0
(Potential transmitters of some pack)88.5 435.2 Q
(et refrain from the transmission of that pack)-.11 E(et because the)
-.11 E(y)-.165 E(detect its duplicate.)88.5 448.2 Q F1(Elimination)72
477.8 Q F0 2.75(Ap)88.5 490.8 S(otential forw)-2.75 E
(arder of some pack)-.11 E(et refrains from forw)-.11 E
(arding that pack)-.11 E(et because it has a)-.11 E
(record of already ha)88.5 503.8 Q(ving forw)-.22 E
(arded a duplicate of that pack)-.11 E(et.)-.11 E F1(Aggr)72 533.4 Q
(egation)-.198 E F0
(Multiple identically sized operands are combined in a bit-wise f)88.5
546.4 Q(ashion that results in a)-.11 E
(compositely encoded operand of the same size.)88.5 559.4 Q F1
(Accumulation)72 589 Q F0(Multiple operands are concatenated together t\
o form an operand list whose length is greater)88.5 602 Q
(than length of an)88.5 615 Q 2.75(yo)-.165 G 2.75(ft)-2.75 G
(he constituent operands.)-2.75 E F1(12.)72 654 Q/F3 14/Times-Bold@0 SF
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