rfc1341.ps

RFC 的详细文档！

720 2080(ASCII].)N
1058(Since)X
1304(RFC)X
1517(822)X
1693(does)X
1901(not)X
2057(specify)X
2368(mechanisms)X
2877(for)X
3022(mail)X
3227(containing)X
3667(audio,)X
3938(video,)X
720 2192(Asian)N
977(language)X
1358(text,)X
1560(or)X
1673(even)X
1888(text)X
2066(in)X
2173(most)X
2392(European)X
2793(languages,)X
3234(additional)X
3652(speci\256cations)X
720 2304(are)N
862(needed)X
720 2528(One)N
912(of)X
1024(the)X
1174(notable)X
1491(limitations)X
1937(of)X
2050(RFC)X
2264(821/822)X
2612(based)X
2864(mail)X
3069(systems)X
3406(is)X
3503(the)X
3654(fact)X
3832(that)X
4010(they)X
720 2640(limit)N
928(the)X
1071(contents)X
1417(of)X
1522(electronic)X
1928(mail)X
2124(messages)X
2511(to)X
2610(relatively)X
2999(short)X
3215(lines)X
3421(of)X
3525(seven-bit)X
3902(ASCII.)X
720 2752(This)N
920(forces)X
1184(users)X
1410(to)X
1514(convert)X
1832(any)X
2000(non-textual)X
2468(data)X
2658(that)X
2832(they)X
3027(may)X
3223(wish)X
3434(to)X
3539(send)X
3745(into)X
3925(seven-)X
720 2864(bit)N
859(bytes)X
1099(representable)X
1650(as)X
1767(printable)X
2147(ASCII)X
2434(characters)X
2862(before)X
3145(invoking)X
3524(a)X
3604(local)X
3829(mail)X
4038(UA)X
720 2976(\(User)N
969(Agent,)X
1264(a)X
1343(program)X
1705(with)X
1912(which)X
2183(human)X
2481(users)X
2714(send)X
2926(and)X
3101(receive)X
3416(mail\).)X
3680(Examples)X
4096(of)X
720 3088(such)N
932(encodings)X
1358(currently)X
1742(used)X
1954(in)X
2065(the)X
2219(Internet)X
2555(include)X
2875(pure)X
3082(hexadecimal,)X
3630(uuencode,)X
4058(the)X
720 3200(3-in-4)N
1006(base)X
1228(64)X
1375(scheme)X
1715(speci\256ed)X
2108(in)X
2234(RFC)X
2466(1113,)X
2733(the)X
2902(Andrew)X
3262(Toolkit)X
3598(Representation)X
720 3312([ATK],)N
1029(and)X
1192(many)X
1430(others.)X
720 3536(The)N
901(limitations)X
1345(of)X
1456(RFC)X
1668(822)X
1843(mail)X
2046(become)X
2377(even)X
2590(more)X
2819(apparent)X
3182(as)X
3294(gateways)X
3684(are)X
3834(designed)X
720 3648(to)N
832(allow)X
1083(for)X
1232(the)X
1387(exchange)X
1788(of)X
1905(mail)X
2114(messages)X
2514(between)X
2872(RFC)X
3090(822)X
3271(hosts)X
3505(and)X
3681(X.400)X
3955(hosts.)X
720 3760(X.400)N
994([X400])X
1308(speci\256es)X
1676(mechanisms)X
2189(for)X
2338(the)X
2493(inclusion)X
2883(of)X
3000(non-textual)X
3476(body)X
3705(parts)X
3930(within)X
720 3872(electronic)N
1133(mail)X
1337(messages.)X
1780(The)X
1962(current)X
2267(standards)X
2662(for)X
2806(the)X
2956(mapping)X
3325(of)X
3437(X.400)X
3706(messages)X
4101(to)X
720 3984(RFC)N
929(822)X
1101(messages)X
1492(specify)X
1798(that)X
1971(either)X
2220(X.400)X
2486(non-textual)X
2954(body)X
3175(parts)X
3391(should)X
3676(be)X
3796(converted)X
720 4096(to)N
822(\(not)X
1004(encoded)X
1352(in\))X
1485(an)X
1602(ASCII)X
1878(format,)X
2185(or)X
2291(that)X
2462(they)X
2654(should)X
2936(be)X
3053(discarded,)X
3472(notifying)X
3851(the)X
3995(RFC)X
720 4208(822)N
895(user)X
1086(that)X
1262(discarding)X
1694(has)X
1853(occurred.)X
2269(This)X
2471(is)X
2566(clearly)X
2860(undesirable,)X
3359(as)X
3470(information)X
3956(that)X
4133(a)X
720 4320(user)N
905(may)X
1096(wish)X
1302(to)X
1402(receive)X
1706(is)X
1795(lost.)X
2007(Even)X
2230(though)X
2522(a)X
2590(user's)X
2844(UA)X
3006(may)X
3196(not)X
3343(have)X
3549(the)X
3691(capability)X
4096(of)X
720 4432(dealing)N
1032(with)X
1231(the)X
1377(non-textual)X
1844(body)X
2064(part,)X
2266(the)X
2412(user)X
2600(might)X
2853(have)X
3063(some)X
3294(mechanism)X
3761(external)X
4101(to)X
720 4544(the)N
875(UA)X
1050(that)X
1232(can)X
1403(extract)X
1703(useful)X
1975(information)X
2467(from)X
2691(the)X
2846(body)X
3075(part.)X
3310(Moreover,)X
3750(it)X
3841(does)X
4053(not)X
720 4656(allow)N
973(for)X
1124(the)X
1281(fact)X
1465(that)X
1649(the)X
1806(message)X
2171(may)X
2376(eventually)X
2817(be)X
2947(gatewayed)X
3398(back)X
3619(into)X
3808(an)X
3939(X.400)X
720 4768(message)N
1080(handling)X
1451(system)X
1752(\(i.e.,)X
1960(the)X
2112(X.400)X
2383(message)X
2743(is)X
2840("tunneled")X
3283(through)X
3615(Internet)X
3948(mail\),)X
720 4880(where)N
979(the)X
1121(non-textual)X
1584(information)X
2063(would)X
2327(de\256nitely)X
2715(become)X
3039(useful)X
3298(again.)X
720 5104(This)N
943(document)X
1375(describes)X
1785(several)X
2110(mechanisms)X
2638(that)X
2836(combine)X
3221(to)X
3349(solve)X
3605(most)X
3845(of)X
3978(these)X
720 5216(problems)N
1119(without)X
1454(introducing)X
1938(any)X
2117(serious)X
2429 0.2227(incompatibilities)AX
3118(with)X
3329(the)X
3487(existing)X
3832(world)X
4096(of)X
720 5328(RFC)N
925(822)X
1093(mail.)X
1337(In)X
1441(particular,)X
1859(it)X
1937(describes:)X
720 5552(1.)N
846(A)X
945(MIME-Version)X
1572(header)X
1859(\256eld,)X
2084(which)X
2349(uses)X
2544(a)X
2617(version)X
2930(number)X
3254(to)X
3360(declare)X
3670(a)X
3744(message)X
4101(to)X
1008 5664(be)N
1154(conformant)X
1653(with)X
1878(this)X
2071(speci\256cation)X
2612(and)X
2805(allows)X
3110(mail)X
3336(processing)X
3801(agents)X
4101(to)X
1008 5776(distinguish)N
1491(between)X
1874(such)X
2112(messages)X
2537(and)X
2738(those)X
3003(generated)X
3440(by)X
3598(older)X
3858(or)X
4000(non-)X
720 6160(Borenstein)N
1161(&)X
1260(Freed)X
3853([Page)X
4096(1])X

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12 s 12 xH 0 xS 1 f
720 400(RFC)N
925(1341)X
1545(MIME:)X
1857(Multipurpose)X
2399(Internet)X
2723(Mail)X
2929(Extensions)X
3784(June)X
3984(1992)X
1008 688(conformant)N
1476(software,)X
1855(which)X
2114(is)X
2202(presumed)X
2600(to)X
2699(lack)X
2884(such)X
3084(a)X
3151(\256eld.)X
720 912(2.)N
844(A)X
941(Content-Type)X
1505(header)X
1791(\256eld,)X
2015(generalized)X
2489(from)X
2705(RFC)X
2915(1049)X
3136([RFC-1049],)X
3658(which)X
3922(can)X
4085(be)X
1008 1024(used)N
1211(to)X
1313(specify)X
1618(the)X
1763(type)X
1955(and)X
2120(subtype)X
2445(of)X
2551(data)X
2738(in)X
2839(the)X
2983(body)X
3201(of)X
3307(a)X
3376(message)X
3728(and)X
3893(to)X
3994(fully)X
1008 1136(specify)N
1310(the)X
1452(native)X
1712(representation)X
2282(\(encoding\))X
2723(of)X
2827(such)X
3027(data.)X
1008 1360(2.a.)N
1227(A)X
1352("text")X
1631(Content-Type)X
2222(value,)X
2511(which)X
2802(can)X
2992(be)X
3139(used)X
3371(to)X
3503(represent)X
3913(textual)X
1296 1472(information)N
1786(in)X
1896(a)X
1974(number)X
2303(of)X
2418(character)X
2807(sets)X
2986(and)X
3160(formatted)X
3569(text)X
3748(description)X
1296 1584(languages)N
1705(in)X
1804(a)X
1871(standardized)X
2382(manner.)X
1008 1808(2.b.)N
1213(A)X
1319("multipart")X
1788(Content-Type)X
2361(value,)X
2632(which)X
2905(can)X
3077(be)X
3206(used)X
3420(to)X
3533(combine)X
3903(several)X
1296 1920(body)N
1512(parts,)X
1747(possibly)X
2091(of)X
2195(differing)X
2556(types)X
2783(of)X
2887(data,)X
3096(into)X
3270(a)X
3337(single)X
3591(message.)X
1008 2144(2.c.)N
1229(An)X
1404("application")X
1969(Content-Type)X
2562(value,)X
2854(which)X
3148(can)X
3341(be)X
3491(used)X
3726(to)X
3860(transmit)X
1296 2256(application)N
1792(data)X
2020(or)X
2167(binary)X
2480(data,)X
2732(and)X
2938(hence,)X
3254(among)X
3582(other)X
3846(uses,)X
4101(to)X
1296 2368(implement)N
1733(an)X
1848(electronic)X
2253(mail)X
2449(\256le)X
2596(transfer)X
2914(service.)X
1008 2592(2.d.)N
1200(A)X
1293("message")X
1721(Content-Type)X
2280(value,)X
2537(for)X
2673(encapsulating)X
3227(a)X
3294(mail)X
3490(message.)X
1008 2816(2.e)N
1171(An)X
1312("image")X
1674(Content-Type)X
2233(value,)X
2490(for)X
2626(transmitting)X
3116(still)X
3285(image)X
3545(\(picture\))X
3901(data.)X
1008 3040(2.f.)N
1184(An)X
1325("audio")X
1665(Content-Type)X
2224(value,)X
2481(for)X
2617(transmitting)X
3107(audio)X
3345(or)X
3449(voice)X
3682(data.)X
1008 3264(2.g.)N
1220(A)X
1333("video")X
1693(Content-Type)X
2272(value,)X
2549(for)X
2706(transmitting)X
3217(video)X
3476(or)X
3601(moving)X
3940(image)X
1296 3376(data,)N
1505(possibly)X
1849(with)X
2044(audio)X
2282(as)X
2386(part)X
2560(of)X
2664(the)X
2806(composite)X
3226(video)X
3464(data)X
3649(format.)X
720 3600(3.)N
845(A)X
943 0.1276(Content-Transfer-Encoding)AX
2036(header)X
2322(\256eld,)X
2546(which)X
2810(can)X
2973(be)X
3093(used)X
3299(to)X
3404(specify)X
3712(an)X
3833(auxiliary)X
1008 3712(encoding)N
1398(that)X
1580(was)X
1766(applied)X
2087(to)X
2199(the)X
2354(data)X
2552(in)X
2664(order)X
2904(to)X
3016(allow)X
3267(it)X
3357(to)X
3468(pass)X
3669(through)X
4004(mail)X
1008 3824(transport)N
1374(mechanisms)X
1874(which)X
2133(may)X
2323(have)X
2529(data)X
2714(or)X
2818(character)X
3196(set)X
3327(limitations.)X
720 4048(4.)N
845(Two)X
1050(optional)X
1395(header)X
1681(\256elds)X
1919(that)X
2094(can)X
2258(be)X
2379(used)X
2585(to)X
2690(further)X
2982(describe)X
3333(the)X
3481(data)X
3672(in)X
3777(a)X
3850(message)X
1008 4160(body,)N
1248(the)X
1390(Content-ID)X
1852(and)X
2015(Content-Description)X
2825(header)X
3106(\256elds.)X
720 4384(MIME)N
1014(has)X
1175(been)X
1390(carefully)X
1766(designed)X
2141(as)X
2254(an)X
2378(extensible)X
2802(mechanism,)X
3298(and)X
3470(it)X
3557(is)X
3654(expected)X
4031(that)X
720 4496(the)N
906(set)X
1081(of)X
1229(content-type/subtype)X
2105(pairs)X
2359(and)X
2565(their)X
2809(associated)X
3272(parameters)X
3762(will)X
3979(grow)X
720 4608(signi\256cantly)N
1245(with)X
1465(time.)X
1734(Several)X
2072(other)X
2319(MIME)X
2630(\256elds,)X
2912(notably)X
3251(including)X
3665(character)X
4069(set)X
720 4720(names,)N
1017(are)X
1162(likely)X
1409(to)X
1511(have)X
1720(new)X
1907(values)X
2180(de\256ned)X
2490(over)X
2688(time.)X
2935(In)X
3041(order)X
3270(to)X
3371(ensure)X
3648(that)X
3819(the)X
3963(set)X
4096(of)X
720 4832(such)N
922(values)X
1194(is)X
1284(developed)X
1706(in)X
1807(an)X
1924(orderly,)X
2252(well-speci\256ed,)X
2842(and)X
3008(public)X
3276(manner,)X
3616(MIME)X
3904(de\256nes)X
720 4944(a)N
793(registration)X
1262(process)X
1580(which)X
1845(uses)X
2040(the)X
2188(Internet)X
2518(Assigned)X
2905(Numbers)X
3287(Authority)X
3691(\(IANA\))X
4024(as)X
4133(a)X
720 5056(central)N
1045(registry)X
1401(for)X
1575(such)X
1813(values.)X
2169(Appendix)X
2610(F)X
2725(provides)X
3118(details)X
3432(about)X
3709(how)X
3937(IANA)X
720 5168(registration)N
1183(is)X
1271(accomplished.)X
720 5392(Finally,)N
1042(to)X
1142(specify)X
1445(and)X
1609(promote)X
1955 0.1953(interoperability,)AX
2599(Appendix)X
3004(A)X
3099(of)X
3205(this)X
3370(document)X
3776(provides)X
4133(a)X
720 5504(basic)N
943(applicability)X
1451(statement)X
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1983(a)X
2051(subset)X
2316(of)X
2421(the)X
2564(above)X
2819(mechanisms)X
3320(that)X
3490(de\256nes)X
3787(a)X
3854(minimal)X
720 5616(level)N
932(of)X
1036("conformance")X
1641(with)X
1836(this)X
1999(document.)X
720 6160(Borenstein)N
1161(&)X
1260(Freed)X
3853([Page)X
4096(2])X

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12 s 12 xH 0 xS 1 f
720 400(RFC)N
925(1341)X
1545(MIME:)X
1857(Multipurpose)X
2399(Internet)X
2723(Mail)X
2929(Extensions)X
3784(June)X
3984(1992)X
720 688(HISTORICAL)N
1316(NOTE:)X
1649(Several)X
1964(of)X
2070(the)X
2214(mechanisms)X
2716(described)X
3111(in)X
3212(this)X
3378(document)X
3785(may)X
3978(seem)X
720 800(somewhat)N
1170(strange)X
1508(or)X
1648(even)X
1890(baroque)X
2260(at)X
2390(\256rst)X
2599(reading.)X
2996(It)X
3115(is)X
3238(important)X
3672(to)X
3806(note)X
4031(that)X
720 912(compatibility)N
1265(with)X
1466(existing)X
1802(standards)X
2196(AND)X