rfc1237.ps

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

(address.)k(However)n(,)c(if)e(the)g(area)0 1172 y(addresses)j(do)f(not)g
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h(level)f(2)h(only)m(,)g(and)g(only)f(level)g(2)0 1229 y(routing)f(packets)h
(would)f(\257ow)i(on)e(the)h(link.)18 b(External)12 b(links)f(\(i.e.,)j(to)e
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(in)f(dif)o(ferent)h(routing)e(domains.)0 1391 y(DIS10589)g(provides)f(an)i
(optional)e(partition)g(repair)h(function.)16 b(In)10 b(the)g(unlikely)f
(case)i(that)f(a)g(level)g(1)g(area)h(becomes)0 1448 y(partitioned,)g(this)f
(function,)h(if)g(implemented,)g(allows)f(the)i(partition)e(to)h(be)g
(repaired)h(via)f(use)h(of)f(level)g(2)h(routes.)0 1554 y(DIS10589)18
b(requires)h(that)f(the)h(set)f(of)h(level)f(2)h(ISs)g(be)g(connected.)39
b(Should)18 b(the)g(level)h(2)f(backbone)h(become)0 1611 y(partitioned,)11
b(there)g(is)g(no)g(provision)f(for)i(use)f(of)h(level)f(1)g(links)f(to)h
(repair)h(a)g(level)f(2)g(partition.)0 1717 y(In)g(unusual)f(cases,)i(a)f
(single)f(level)h(2)g(IS)h(may)e(lose)h(connectivity)f(to)g(the)h(level)g(2)g
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(indicate)g(in)g(its)g(level)h(1)g(routing)e(packets)i(that)f(it)g(is)h(not)f
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1830 y(area)i(to)f(route)g(traf)o(\256c)i(for)e(outside)f(of)i(the)f(area)h
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(route)f(traf)o(\256c)h(to)0 1886 y(destinations)e(outside)h(of)h(their)f
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(1)h(routing)f(packets)h(that)0 1943 y(they)e(are)h(attached.)0
2049 y(An)f(ES)h(may)g(autocon\256gure)f(the)h(area)h(portion)d(of)i(its)f
(address)g(by)h(extracting)f(the)g(area)i(portion)e(of)g(a)h(neighboring)0
2105 y(IS')m(s)e(address.)16 b(If)9 b(this)f(is)g(the)h(case,)h(then)f(an)g
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b(Since)9 b(the)g(standard)f(does)0 2162 y(not)h(specify)g(that)g(the)g(end)h
(system)e Fb(must)h Fi(autocon\256gure)g(its)g(area)h(address,)g(an)g(end)f
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(address.)26 b(In)15 b(this)f(case)h(the)g(end)g(system)e(would)h(ignore)g
(IS)i(neighbors)e(with)g(non-matching)f(area)0 2275 y(addresses.)0
2678 y(Colella,)f(Gardner)n(,)g(&)f(Callon)1243 b([Page)12
b(9])p eop
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bop 0 50 a Fi(RFC)13 b(1237)281 b(Guidelines)10 b(for)i(OSI)g(NSAP)g
(Allocation)e(in)h(the)g(Internet)293 b(July)11 b(1991)0 195
y Fh(3.3)50 b(Requir)o(ements)12 b(of)g(DIS10589)g(on)g(NSAPs)0
332 y Fi(The)i(preferred)h(NSAP)g(format)e(for)h(DIS10589)g(is)f(shown)g(in)g
(Figure)i(1.)23 b(A)14 b(number)g(of)g(points)e(should)h(be)h(noted)0
389 y(from)d(DIS10589:)68 545 y Fc(\017)23 b Fi(The)9 b(IDP)h(is)f(as)g
(speci\256ed)h(in)f(ISO)h(8348/Addendum)d(2,)j(the)g(OSI)g(network)f(layer)g
(addressing)g(standard)g([14];)68 638 y Fc(\017)23 b Fi(The)c(high-order)f
(portion)g(of)h(the)g(DSP)h(\(HO-DSP\))g(is)f(that)f(portion)g(of)h(the)g
(DSP)g(whose)g(assignment,)114 695 y(structure,)11 b(and)h(meaning)e(are)i
(not)f(constrained)g(by)g(DIS10589;)68 789 y Fc(\017)23 b Fi(The)13
b(concatenation)f(of)h(the)g(IDP)g(and)g(the)g(HO-DSP)-5 b(,)14
b(the)e(area)i(address,)g(must)e(be)g(globally)g(unique)g(\(if)h(the)114
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(addresses)f(of)g(a)g(system,)g(it)f(is)g(in)h(the)g(system')m(s)f(area)114
902 y(and)g(is)g(routed)g(to)g(by)g(level)g(1)g(routing\);)68
995 y Fc(\017)23 b Fi(Level)10 b(2)h(routing)e(acts)i(on)f(address)h
(pre\256xes,)g(using)f(the)g(longest)g(address)h(pre\256x)g(that)f(matches)g
(the)g(destina-)114 1052 y(tion)g(address;)68 1146 y Fc(\017)23
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b(one-octet)h(NSAP)g(Selector)n(,)h(SEL,)f(determines)f(the)g(entity)f(to)i
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(identi\256ed)h(by)g(the)h(rest)f(of)h(the)g(NSAP)g(\(i.e.,)h(a)f(transport)f
(entity\))g(and)h(is)f(always)g(the)h(last)f(octet)g(of)114
1409 y(the)e(NSAP;)h(and,)68 1503 y Fc(\017)23 b Fi(A)14 b(system)g(shall)g
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g(8348/Addendum)e(2.)27 b(However)n(,)16 b(within)e(a)h(routing)e(domain)h
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(of)h(the)f(NSAP)h(should)f(be)h(structured)f(as)g(the)h(ID)g(and)f(SEL)h
(\256elds)114 1672 y(shown)9 b(in)i(Figure)f(1)h(to)f(take)h(full)f
(advantage)g(of)h(DIS10589)f(routing.)16 b(End)10 b(systems)f(with)h
(addresses)g(which)114 1728 y(do)15 b(not)g(conform)h(may)f(require)i
(additional)d(manual)h(con\256guration)h(and)g(be)g(subject)f(to)g(inferior)h
(routing)114 1785 y(performance.)0 1941 y(For)h(purposes)e(of)h(ef)o
(\256cient)h(operation)f(of)g(the)g(IS-IS)h(routing)e(protocol,)i(several)g
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2678 y(Colella,)h(Gardner)n(,)g(&)f(Callon)1220 b([Page)12
b(10])p eop
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bop 0 50 a Fi(RFC)13 b(1237)281 b(Guidelines)10 b(for)i(OSI)g(NSAP)g
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