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RFC 418: Server File Transfer Under TSS/360 At NASA-Ames Research Center

  • W. Hathaway
Unknown
Page 1: ' 1 2.762 NETI-l OHK WORK I JG GROU ? Hayne Hathawa y ( flJ.1E S- 6 7) Requ est for Comm en t s ~418 Novembe r 27 , 197 2 Nr c if1 276 2 Ca t e gor i e s D. 7 , G. 3 Se r ve r Fi le Tr ansfer Und er TSS /3 60 At NASA-Am e s r esea r c h Cen t e r r ni s RFC i s a des cr iption o f the i ni t i a l ~mp l e m e n t a t i 0 n o f Se r v e r Fi le Tr a n sf e r. at N,\ S -I. -Ames r e s e ar ch Ce nt r , I t a l s o c o n t a in s s ome c c mm e n t s on t he c u r r e n ~ Fil e Tran s f e r Pro t oco l ( RFC' s 354 -od 3 85) and so me s ugge s ti on s f or fut ur.e ex ens i on s . Comme n t s or que s ti on s s ho u ld be di r ect e d t o : ' .J ay ne Ila r haway Na il St op 233 -9 i TA SA- ne s Rese a r ch Cent e r Ho f f e tt Fie l d , C l~ 9l~ 0 3 5 (415 ) 965 - 6033 or (408 ) 736- 7439
Page 2: RFC 418 Pa ge 2 TI1e k1PA Net wor k =ilc t ransf er f acilities p r o v i d e d a t Ames i n t e r f a c e v e r y cl o s e ly with the st an d a rd TSS fi l e man a g ement f a cility; n etwor k u s e r s s h o u l d b e f arai I iar wit h TSS in g e n e r a l a nd its f i Le handling c a p a b i l i t i e s i n part ic u la r . A few o f the ba si c con c epts are me n tione d h e r e. Ea ch per so n a llowe d t o use TSS i s as si g n ed a use r id en t if icat i o n ( USERI D) , wh i c h i s pa dded to eight cha r a c te rs ui th a ste r i s k s by the s y s t eru, At Am e s , t h e u s e r i d is norm ally f o rme d from a three l.e t t er o r g a n i z a t i o n co d e a nd the us e r I s Ln i t i a l s , Ea c h us e r i d has its own catalog ( d i r e ctor y ) , wh i c h co n t s ins poi n te r s to a ll da t a s e t s (files) wh i c h may be acc e s s e d by t he u s e r . TSS da ta set n am es a re ma de up of one or more cu al i f ic a t ion l e v el s, up to e igh t ch ar a ct er.s each, sep ar ated by pe r io d s . 1 h c highes t qu a l i f ic a t io n l c ve~ is in fac t the u s er i d , but t his i s no t En tered whe n s p ec i f y i n g da t as e '; n ame s ; t h e c ur r e n t l y a c t i v e uBerid i s a pp e nded by t h e s ystem to al l n m: es entered hy the user . The Leve ln o f. q ua l ifi cat i on form a t r e e s t r u c t u r e wh ich may be us ed t o i d e n t i f y lo g ical gr o u ps of da t a s ets . Only ends o f br -nch es a ctually n am d a t asc t s ; suc h n aine s are t e rrne d " f u l l y qualified " n am es . Pa r ti al ly qu a li f i e d narne s a re u s e d i n man y TSS d a ca s e t man age ment c omma n d s but a r e no t u s e d in AI{ PA Ne tw o r k Fi l e Tr an sf er . Host d atase t s u n d e r TSS are co n t a L ne d o n a po ol of un ivers a ll y a va ilable disks tenne d " p ub l i c s to r,g e . " Da t s e t s o n p u blic s to rdg c ar e au t omatica lly c a t a l o g e d at c r e ...,t i o n . Da t a s e t s may al so e x is t on pr iva t e d e vi ce s , eit her d i s k s o r t a p es . Pri v a t dat as et s may be c 3t a lo g e d or n o t , a s the u ser d e s Lr-e s , On I y disk datas e t s i n the " v i rt u a l a c c e s s me t h od " ( VAH) are s up po r t e d by TSS Ser v er F il e Tr a n sfer , but private ViI:'1 datas ets may be use d .: f c a t a l o g e d . Ampl e TSS co mmands exi s t for tr a n s ferri n g VJJ:1 d a t a s et s t o t a pe , c a r d s, pri nter , etc . The TS S c a t a l o g struc ture a lso a Ll ows ex t e n s i v e sh ar in g of d a t a s e c s amon g u s ers. Th i.s 'har in g n:ay he don e a t ny q:.la li fic a tion le ve l nd wL th rea d -onl y , r e ad-wr i t e , o r u al i mi ted ac c e s s ( o n l y unl imited sh aring a ll ows e r as I ng ) , To shar e a TSS da .a s e t , r.he owne r must firs t " pe rm i t " it t o on e or mor e u s e r s , Each u s er must the n e x pl i c i t l y " s h a r e " i t, wh i ch c a u s e s a n e n t r y for t h e d atase t t o be mad e i n hi s c at a l o g . T his e n try , which ma y he u nd er a dif f erent n ame t h an the o ri gin al, do e s n o t poi n t t o the d a t a s et it s e l f , b u t rathe . ~ p o i n t s to t h e appropr i ate e ntry i n th e own e r IS c a t a l o g , T i s a l l ows t ' e own e r t o c h a n g e o r re mo ve s h a r i n g acc ess a t any im e . TS S FI LE ST RGCTU RE 1\ b r i e f discus s ion is al s o i n r d e r ab o u t the d iffere nc e be twe c n un st r u c t u r e d f iles a nd re c o r d - s truc t u re d f il e s . All f i l e s on TSS are st o r e d 'Io1 i t h so me f o rm o f re cord s ru e t ure , a I tho u gh eac h r ecord may be u p t o on e mi l lion byt es i n l e n g t h; the i mpo r t a n t thing i s the mean i ng a t tribut ed to a record . F or har a c t e r o rie nt ed d a t a s e t s (e. g . , s ou rc e pro gr ams , l i s ti n gs, pr ogr am d o cum en t a t i on ) a r ec o r d c orr e s p o nd s to a 1 i n c ; t h e r c ar e no end -of r ec o r d mark e rs in the da t a it s el f (C R-L?, NL, r:OL) . Th e TSS e d i t o r s require t his , t h e t r r.ns l a t o r s re q uir e thi s and so for t h. Thi s do es not p r e c l ud e h av i .n g a n EBCDIC "n ew- Li n c " cl a ra c te r ( NL) in h e c a t a , how
Page 3: RFC 4 18 Pa ge 3 ever ; it is ju st trea t e d as par t o f th e l i n e of d at a . . hus ch a r ac t e r o riented fi les must be sen t to and sto r ed on TSS , .... it h r e co rd s t r uc turing t o c us e f u l : The u s e o f uns t r uc t ur ed f i l e s on TSS i s us ually rest r i cted t o b in a r y d ata and ob j e c t pro gr ams . Fr om t he net ' .... o rk t h e onl y u s e fo r s u ch f i l e s wou ld be d at a whi c h i s in fa ct a t o t a l ly uns tr u ctur e d s t r i n g o f b i t s (us i ng INAGE type). An examp le mi gh t be a n ob j e c t pr ogr am for an IHLAC. Be cau se o f th e abo ve , ou r s erv e r h as imp le ment ed t he fol lo wi ng c on ve ntions . Sendin ~ str uctured dat a ( RETR, STRU R) : An end-o f -r ecord eq ue n ce wi l l b' add e d to e a c h r e c or d rea d fr om t he TSS da t a s t (e i t he r " s t r e am" mode CI - LF o r " t ex t " mode Ea R) . Sen di ng un st r uc t ur ed d at a (RETR, STRU F): The da t a ~ i l l be sent wi t h no en d- of - re c or d se qu e nc e a dde d . Re c ei vi ng s tr uc tu r e d d t a ( STa R or PPE, STRU R) : An e d- o f-r e c or d s equ n ce i s r e qu i r ed t o def i ne e ac h TSS re c or d (wi t h a me xim um r ec or d len g t h o f 101 2 by t e s ). Rec e i v i ng un s t r u ct ur ed data ( STOR or APP E, STRU F) : Ever y c har a c te r r eceiv ed i s wr i tt en i.n t o a rb i tr ary s i z e d r e c or d s ( ex ce p t fer " text" mode EO F ch a r ac t e r ) . The abo ve Ln p l e.. e n t a t i on does sa ti s fy one c r i t e r i on ( a s state d in t he t h i r d sentenc e of I I I . C i RFC 35 4) : an y f i l e sent t o TS S may be r e tri sv e d ex a ctly a s sen t . F r ex amp le , t hi s me ans t h at i f a c hara c te r f ile i s s ent in uns truc t ur ed form , the CR- LF s e quenc e s wi l l be s t or e d as p&rt of t he d ata. \ ~ l en this dat a s e t i s r c t r i ev ed (a l s o in un st r uc t ur ed fo rm) no new e nd - of - re c or d i nd i c a t or s vri .Ll, be adde d, s o t he re t r i eve d fi le wil l have onl y the or ig in a l CR- LF rec or d i n fo rma t i on . If th e file wer e re t r i e ved in reco r d-struc tu r c:.d form , howev e r , th i s woul d of co ur s e no t be t he c a s e ; i t i s impo rt an t th at any unstr uc t ure d f ile be r e t ri eve d i n ex actly t he s ame manne r t ha t i t was s en t . This c r i t e r i on o f retr iev abili ty is no t t he ma i n one o f conc er n t o TSS us e r B, ho\ ev er ; a a re i mpor ta n t c ri t eri on is t ha t f i l e s sen t t o TSS may be of us e on th at s yste m ( L e . , may be e di t ed, may be pr in ted , e tc . ) . To a cco mp lish 'h i s i t i s imperat iv e th a t cha r a c t e r data be sen t wi t h record st ructu r e . As ca n be se en f r om th e a bove d i scus s ion , th i s should n ot b . a pr ob l em \.;i th rn o s t ha s t s , as in d f a ul t t r , ns f e r s (MODE S, TYPE A) t h ey are a l ready i n lu d i n g e n d-o f- r e c ord info rma i on a t t he e nd o f e a ch ph ysi c a l 1 i.n e ( CR- LF) . Thu s th e on l y r e qu i r mont wou l d be t o no t r e j e c t t he STRU R c omm a nd ( a t le a s t in NODE S, TYP E A t r an s f e r s) . Thi s may c a us e
Page 4: RFC 4 18 Pa ge 4 s ome min or pr ob l ems ( s uch · s CR- L -L F- LF- LF f or ve r t i ca l s pa ci n g) bu t it i s str ong ly re uested that host s whi c h do not us ua ll y st ore f il e s in re c or d - st ructure form at l e as t i mpl eme nt ST RU R i n th i s s imp le c on t ex t. TSS SERVER FILE TRA..~SF E !( nlPLENENTATIOj:~ The TSS i mpl emen t a ti on of ea ch o f t he fi l e t r a ns f e r c omm a nd s is de s c r i be d be l ow. The maximum length for a c omman d and its paramete r s i s 256 ch a r a c t e r s (no t including t he CR- LF a t t he end ) . All blank s a r e r emove d from t he parame er st r ing , aId s o b l an "s ar e ne ver si gni f i ca nt e xc e p t t o sep~rate a co m~and f rom its pa r ~~ e ters. Onl y he c omm ands HAIL and MLFL may be u s ed when the re i s no ac ti ve u s e r l ogged 0 1. ; al l o t he r co .mna nds r e q ui r e n p ri or USER comm and . The USER c omm and de f i ne s t he TSS lls e r i d t o be emp lo ye d f or c a t a l og a c c e s s . Thi s must be a va l i d TSS use r id , but it mus t a l s o h av e be e n s pe c i f i ed as h a vi ng a c cess t o ne t wor k fi l e t ransfe r . Th i s is do ne by i ns t a ll a t i on manageme nt in a anne r s i mi l ar t o e stabli sh ing a v a l i d TSS us e r i d ; con t a c t Wa yne Hat ha way t o h av e exi s t ing TSS user ids jo i ne d t o ARPA Ne t wor k Fi le Transfe r. The demon st r at i on u serids ARPA, AR PA1 , a nd ARPA2 do h.::? ve a c c e s s t o f i l e t r a n s f e r . The USER c Olmn a nd also r e s e t s a l l f i l e tra n sf e r paramete r s t o t he i r de f a u l t va lues , i nc l u di ng HOST a nd SO CK. It is f e l t t h i s s h ou l d have b e e n spe cif ied in t he pr o to co l . I f a USE R co . and is e nt e r e d dur i ng a f i le l: r a n s f e r op e r a ti on i t wi l l be hc: l d u nt i 1 the t r a n s f e r i s c om p le e ; he new us e r i d \"i 11 he n be p roc e s s e d , a p a s swo r d may be requested , et c . P SS TSS fi le t r an s r e r pas sw or ds are o p t i on al a nd a r e e s t ab li s he d when use r i ds ar e gran ed f i:e t r an s f e r acces s . This pa s s ~ ord i s n ot ne cessa r ily th e s ame as t he nOl1nal TSS passvord . The demons t r a t i on use r ids ARP A, ARPAl , a nd ARPA 2 ha ve no pa ssw o r ds . AC CT The ACCT c o mm ~~ d i s no t s uppor t e d . The pro to c ol see ms somewh t defic ie nt i n th e def init io n of t he ACC T comm an d , pa rti c u l a r l y i the assign i ng of r e p l y codes . I wou l d l ike t o pr opos e tha t code 33 1 be ass igned t o " -::: N TI~ R ACeT " when t he ACCT c omma nd i s requ i r ed for "lo g-on" and c ode 1~ 3 3 be a s s i gne .d t o " ENTER ACCT " when the .ecl' c ommand is requ i ted on ly for a part i c ular t r a ns f e r op e r a t ion . It is fel t that this wou ld a i d us er automata i n s a t i s f y i ng p ar t i c u l a r s e r ve r r e qui r emen t s .
Page 5: RFC 4 1 8 Pa g e 5 BYTE Th e o n ly BYTE size s ~pp o r te d is ei ght . SOCK The SOCK c o n:m a n d is supp orted i n ac c or d a nc e ' vi t h th e p r o t oc o l . The re i s o n l y one HOST pa rame te r , how e ve r , wh i c h app l i es t o bo t h s e n d a n d r e c e i v e s o c k ets. TYPE Ty p _ cu rren t ly supp o rted are . SC ll an d ll'lAGE. Th e EBC DI C typ e "7i 11 be a d d e d l at e r . The two " p r i n t f il e " t y pe s a r e n o t y e t su p po r t e d , du e p a r tl y t o la ck of t ime and part ly t o a seen ing fa u l t i n t he pr ot o c o l i t appears t l .e only t r a n sf e r mo d e wh i ch a ll ows a " p r i n t fi l e " i s BLOC K. Th is i s baser. on the d e s c r i p t i on s o f t r a ns :Ee r mod es on pa ge 12 o f RF C 3 51~ : TEXT mod a Ll ows on ly ASCII t yp e, a n d ST RE AH mou e a l Lows r e c o r d st r u c t u r e s (s u r e l y n ec e ss a r y i n p r in t f i les ) o nly in ASCI I ty pe . I a s sum e t h i s j.s an ov er si gh t ; a nd '17(: i n f a c c i n t e n d t o s u pp o r t EBCDI C typ e i n S TRELM mode Hi th r eco rd st r u c t ure s (si n c e EBCDI C c on t a i n s b o th C , and LF ) . I f n o t , th e i mp l eme n t ati o n o f " p ri n t f il e " t yp e s .wi ll be d e l a y e d s u b s ta n t ia l l y . STRU Bot h f i l e a nd rec o r d s tr uc t u r es a r e s u p po r t e d , i n a c co rda nc e Hi th the p r o t o c o l . Th e EBC DI C ty p e ""i ll be s u p po r te d w it h re c o r d st r u c tu r e , h owe v e r , a s i n di c a t ed un d er the TYPE c omman d . r-10D E The STREi\H a nd TEXT modes are c ur r e nt ly s up po r t e d for t he i ndic at e d t y pe s ( STREAH is r e q u ired fo r HIAGE t yp e ) . I n S ':":' REAJ.'1 mod e "7ith reco r d s tr u t u r e s , th e CE- LF s eq u e n c e (wi t h o p t i o n al Te l ne t; NOP ' s ) i s r e quir ed a s EOR. In TEX1 mode Hi t h no re c o r d s t r u ctu r e an y EOR c h ar ac t er s e n c o u n t e re d are dis c ar d e d . I n TEXT mode wi th r ecor d s t r uc t u re a messag e c o n t ai n i n g o nl y a n EOF c h a r ac t e r is as s umed t o be a n e nd- o f - f i l e o nl y , n o t a nu l l r e c o r d ' l7 i th a n a mi t t e d EOR ( a l t ho u g h we wo u Ld l ik e to c on t i.n ue /' o u r l o bb yi ng aga ins t " i mp li e d EOR" c o n c e p t s ! ) . RETR The RETR c omm a n d i s s u p po r t e d i n a c c o r dan c e wi t h th e pr o t o c ol ; . the p a r a me t e r mus t be a fu lly q u a li f i e d n ame o f an e xi s t i n g da ta s e t o n d i re c t a c c e ss st o ra g e (pub l i c o r pri va t e ) . Fo r s t r u c t u r e d fil es i n ASCI I t y pe a " CR·· LF" s eq ue nce i s in se r t e d a t th e e n d o f e ach re c o rd . No EOR ch a r a c t er s a re i n s e r t e d f o r u n s t r u c t u r e d f il e s in TEXT mode . S Ta R T he STOR c onau a n d is S lip o r t e d in a c c o r dan c e wi t h th e p r o t o c o l ; t he pa ra mo t c r mus r be a va lid f u l ly qual if ied d atase t n amc , H it h u n l i mi t e d o r r <' nd - wr i t . a c c e s s requ i r ed f o r e x i s t ing sh a re d d a t a s e t s . The c h a r a c t e r i s l ic s o f t he TSS da ta set be ing sto r ed a r e de t er~ mi ne d a s f ol l ows .
Page 6: RFC 418 Pa ge 6 For new da t a s e t s , th e defau lt ha r a c t e r i s t i c s ar e VS or gani z a tio n wi t h a m axi ml~ r e co r d s i z e o f 1012 byte s . Thi s nay be ove rri d e n by s pe c i f y i ng an ALLO ( TS " DDEF " ) c omm an d ~ ., i th d i f f e r e n t c ha r a c t e r i s t i cs . A 'ISS " l i ne data s e t" may t h us be c r e a t e d by f i r s t e n t e r i ng an ALLO c om mand s pecif ying VI orga ni z a t i on ( li ne n umbe r wi Ll be i n s e rt e d by t he s y s t em). Fo r oth er types of 11 da t a s e t s , ho we ve r , t he us e r must e ns ur e tha t t h e r e c ord s c on t a i n keys in t he sp ec i f ie d pos i t i on s a nd t ha t th ey ar e sent i n or de r by key ; i t i s a n t i ci pa ted t h at t his f ac i l i ty wi l l be r a r e l y u se d . For e x is t i ng da t a s e t s , t he new v e r si on wi l l be c r e a t e d wi t h th e s ame cha r a c t e r i s t i c s a s the or i g i na l ( an d on t he s ame pr i v a te vo l urae) . APPE The APPE command i s suppor t ed i n a c c or dance wi t h t he pr o t oc o l ; t he p ar am e t e r mu st be a va l i d f u ll y qu ali f ie d « a t as e t name, wi th un li mi t e d or r e ad -wr L t e a c c e ss req u ir e d f or ex i s t i ng s ha r e d d at a s ets. The c ha r a ct e r i s tic s o f c r e a t e d da t as e t s a r e d et e r mi.ne d a s fo r th e STaR c omm a n d. RNFR The RN FR co mmand i s su ppor t e d in a c c or'danc e wi t h t h e p roto c o l ; t he pa r a mete r mus t s pe c i fy t he full y qua lif i ed name of a n e x i s t i ng da t a s e t . RNTO The RN TO c o mm a nd i s sup po r te d i n ac c o rd a. i c e wi.t h t he pr ot oc ol ; th e p a r a me t e r must s pe c i f y t he f u l l y qu alif i ed name of a none x i s t en t da t a s e t. DELE Due t o t he 'ISS fi l e s ha r in g and pr i va t e de v i c e fa c il i ti e s, th e si n g l e DELE comm and i s no t re al l y ade qu at e . I n 'ISS th e r e a re t wo s p arat e comm ands f or t h i s fu nctio n , ERASE and DELE TE. The ERA SE c omm a nd i s used t o ac t ua l ly pu r ge a datas et and f r e e it s s pac e ; i t 1 ay be us e d on l y on dire c t a c cess d ata s e ts ( pu bl i c or pr i va te ) wi t h un li mi t ed ac c e s s . The DELETE co mm and s i mpl y r emov s a c a t a l c g en t r y a nd d oe s n ot t ouch t he da t a s et i t s e l f ; i t may be us e d on s ha r e d d a t ~s e t s of any type ( t o e f f e c t i v e l y "un s ha r e " ) o r on da t a se ts on pr i v a te de v ices . To a t t empt to provide bo t h of t h e s e f un c t i o ns , th e DELE c omm an d ha s be e n i mp l e me n ted a s fo llo ws . Fo r non share d a tas ct s : Pub l i c o r pr i v at e d ir e ct- ac c ess : e ra s e ( f r e e t he spa ce ) an d de l et e t he c at al og en t r y Pr iv a t e nond i r e c t- a c c e s s: de l et th e c a t a l o g e ntr y only For s hared da t a s e t s : ~Ib li c or p riv a t e d i r e c t - ~ c c es s , un l i mit e d s ha r i ng : e ras e ( f r e e the spac e ) a nd de le te the c a t a l og e n t r y .
Page 7: RFC 418 Pa ge 7 .1 1 oth ers : d elete t he sharer 's c a t al o g en try on l y ALLO The AL LO c orrman d is se d t o enter a TSS " DDEF11 c o rrm a n d . Thi s may be used to sp ci f y non st a n dard d at aset a ttr ibute s , p ri vat e de i c es, or o t he r i t ems . The par ame ter is a omp let TSS " DDEF" c o rrun and mi nus t he wo r d "DDEF" itse lf, wi t h t he mi no r re str ict ion t ha t t he f irs t t hr e e pa r ame t e r s (DD.TANE, DSOR G, and DSNANE ) mus t be pr e se n t and mus t no t be s pecifi ed i n ke )~ord fo rmat . REST The REST . co mm a nd i s not s upported. It Hill be add e d when BLOC ' mode i s i mp l eme n t e d . STAT There ar e th ree u s e s o f th e STAT c o mm a nd . If u se d b et we e n f i l e t r a ns f er s wi t h no prrrame re r , i t pill pr i nt t he c ur r e nt val ue s f o r a l l f i l e t r an s f e r pa r ame t e r s ( u s e r , by te s i ze , h o s t, r e ce i ve data s o c k e t , s e nd d a t a socke t, tran sfer type, fi le s r uc t ure , a nd t r a n s f e r mode ) . If us e d du r in g a fi l e t ra n sf e r op e ra t i on ( wi t h or wi t hou t a pa r ame t e r ) i t wi l I i nd i c a t e wha t ty pe o f ope r a t i on i s ac tiv e . The t h i r d US2 o f STAT is t o ret r i .v s ta t us i. nf on na t i on abou t a f i le or gr oup o f fil e s (i . e ., any qu ali f ic a t i on Lev e L } , The r e a re t wo fo rms f or this f nf o rma t Lon , t e rm ed shor t nd l ong . Th e short f orm w i Ll, in d ic a t e wh t dat as e ts e" i s t wi h the qualificat io n l e v e l s pe c ifi e d , Hit h i n f or lna t i on abo ut s 1 a r ing an d p ri v at e devi ces . I f the p a r ~n e t e r spe c if ierl is a f u l l y q ual i f i.e d n ame , the e tire da ta se t name i s pr inte d . If i t i s p a r t i a l Ly q ua Lt f i e d , t he names o f al l d a t as e t s in t ha t gr oup ar e print ed (Hi t h o n l y t l e m i q ue por t i on o f the names a ct ua l l y ap pea ri ng ) . Th is . hart f orn i s exactly eq ui valent t o the TSS "PC ?" c omm a nd and i s t he deraul. fOlm fo r STAT. The pa r ame t e r f or t h e:: l ong form ' s t he s ame as f or t he sh or t fo rm , bu t all av ail ~ ble i n f orma t i on is pr inted f o r e a c h data se t (a t lea s t f i ve l ines p e r data set). '1'0 get the lo n g form , t he cha ra c ter s " , LONG" mus t be app e ld ed to t he pa r a~eter . The lo n g fo rm i s e xa c t l y eqUivalen t t o t he TSS " DSS?" c omm a nd . Tt,e TAT c o mm and d oes not c ur rentl send a rep l y co de 200 at al l . I t is elt t his sholld be a dde d to the pr ot oc ol t o be t ter d efine the e n d o f STAT inf o rma t ion ; the r e pl y code 200 wil l be a dd e d at t h a t t ime . LIST The LIST c o mm a nd pr oduc e s ou tpu t i de nt ic a l to the s ho r t and long fo rm ST,\T c omm and ( pa r ame t c r e qu ired ) e xc e p t t h a t th e lo ng form is t he de fault ; to ge t t he short f orm , the chnr a c t er s " , HORT " must be a ppe nded to th e p~r am ete r .
Page 8: RFC 418 Page 8 ABOR Th e ABOR c o mm an d may be en te red a t any ti me dur ing a f i. Le tr ansfer o pe r ation . I t vri Ll c au s e an i mm e di at e t c rmi na t i on o r the t r a n s f r and c l o s in g of th e d~ ta c o n n e c t i o n. Fo r RETR o p er at io n s , the TSS d~ t as e t will b e un aff ect e d. Fo r STOR or APPE 0 a new da t a s e t , ther e will b e no th ing c re a t ed ( e xc e p t poss ib ly n Ln t c rme d i. t e f ile whi ch should be i g no r e d ) . For STOR of 81 exist ing d ataset , th e d atase t wi l l be u n c h a n ge d. F or APPE t o an ex i s t Lu g d a t a s c t , a l l tr a n sf erred i n f o rm a t io n vi. Ll ha ve been wr i . t e n in t o the d a ta s e t. BY E Th e BYE c o mm ar d i s su p po r cd in ac co r d ance ~ 'li h th e pr o t o c o l. I f a ·BYE c o mm a n d is entered du r i n g a t ra n sf e r op erat i on · t he nex t co mm a n d en te rcd (wh i c h mu s t b e a USER co rnm an d ) wi Ll n ot b e p r oc e s s cd a t all u n il t h e t ran sf er is c( .mplet e . Not e t h e t th is p r ec l udes a bo r t i n g the t r a n s f er after a BYE c o ~mand i s e n t er ed (wh i ch s e ems t o f i t the s p iri t of BYE ) . HAIL The l lAI L c onm a n d , .,ill acc e pt a TSS us e r Ld , a kn own NI C i d e n t (L e . , o n e f o r \..hi ch a m. rpp i n g 0 TSS u ser i d exists ) , o r ~ nu ll p ar -ame rc r ( i n wh i.c h c ase t h c ma i l will be sen t to t h e TSS s y s tems pxo gr amm i.n g gr ou p ) . Unl nO\·;'11 ide n t s \.,i 11 c a u s e the NAI L co rrnn n d t o b i gn or e d . The 101 TL c omm. nd may be ente r e d pri o . to t h e f ir t USER c o mm a n d , to i n c r as e th e i.c LLi, t y o f th e ne two r k mai 1 syo em. Th is i s no t c u rr e n t l y mentio ned in t he protocol; it i s f elt tha t t hi s imp lementation s h o ul d be r ee omrnendc I . HLFL The p a r amet er L s t he same as for t he HAI L c omm a n d , The NLFL c o rnm s.n d may als o be enter d pr io r t o a US ER command , f o r t he s ame re aso ns i n d ic at e d und er ~L~IL. c m r-1EN'IS ON 'IE ..:. PRO TO COL Some po s sib le a dd i t ion s t o th e Fi l e Tr a n s f er Comma n d S et re as f o l l ows , NOP I t s e e ms str a n ge t o f in d any pr ot oco l ' '''i th o u t a no - op e rat i on c omm an d , a n d th e re ar e severa l p ossibl e us e s for s uc h a command . As s tnnin g t h e r e is a s p e c i a l reply c od e as s i gn e d to " NOP C O ~ 'l l ' W; ACC EPTED, " t h e n NOP could se r ve .he s ~n e fun ct io n as th e l e vel 2 EC O (fo r user v e r i f i c a t i o n of s er ve r e x is te n ce , fo r e xam p l e ) . Anothe r ex amp le co u ld b e in a ll owing he us e r t o d iscar d term i n a l o u t p u t , as f r om a to o l e n gh t y STAT c ornman d , Th e problem "' ith j us t disc ardin g ever ythin g is th a t th e lIs e r process do e s n ot k n m'" ""he n a l l o u :pu t has be en r eceive d . If a NOP co mma 1u we re c1 -f i ne d , t h e tls er pro c ess c o u ld s e nd a NOP upo n r ec ei pt of t h e dis ca r d r e qu e~t , and t h en di s ca rd un t il t he unique NO P esp o n s e i s rec e i v ed .
Page 9: RFC 418 Pa ge 9 SRVR r The S VR CO l. , a nd wou Ld be used t o pa s s a par ame t e r whi ch ha s ' s i gn i f i c a nc e only t o the p art i cular s er ve r s y s t em. Th i s p ar ame t e r mi gh t s pe cify p rintin g a newl y c r e a t e d fi le , .ov i ng a fi Le , or an y n umbe r of s er v er - de f i ned functions . One o ssi bl e i mp le men t a t io n wou l d be f o r t he pa r ame t e r to be a v a li d s e r v er s yst em c omm a nd , whi c h w u l d t h en be It ob ey ed " by th e s er v er . To s implify i mpl emen t ation o f bo t h SRVR a nd STAT c omm an ds , th e f o L l ow i n g ch a nge t o th e pr oto c o l is req ue s t e d . Be t we en t he re ce i pt o f a STAT or SRVR r.mrnn a nd a nd t he s en d ing o f a rn c ogn iza bl e r e ply co de (i. e., an y mess a ge H.Lt h n umbe r s i.n t he fi rs t t h r e e po si t i ons ) , a s er ve r i s a l l owed to send mess a g es wh i c h do no t h ave va l i d r e p ly c ode s . Thus t he se r ve r 8Y t e rn r e s pon s e mes s age s cou l d be se n t with no mod i f i c a t i on ( e x ce p t to Ln s ur e t h a t the f i rst tree pos i t i o s ar e no t nume r i c ) . The se me s s age s wou l d be assume d t o h a ve co de 000 a nd s hou l d be pr i n te d by a ny us e r pr oce s s e s . Thi s t.e c hn i qu e c ou l d po s s i b l y be ex t e nd e d t o o t he r cOlum ands wi t h goo d r e s u l t s . CLSE Dur i ng i mp emcn t a t i on o f t he Fi l e Tr a n s fer J er v e r th e f ol lo wi ng ope r a t i ng mode was c ons i d e r e d , t ha t of t he s o - ca l l ed It ho t c a r d r e a de r . 1t I n t h i s mode a c onne c t i on wou l d be es t a bl i s hed b et wee n t H O s y s te ms onc e t o be l e f t ~ ~e n for an ex te nde d pe r i od . I nd i v i d ua l us e s wou l d en te r USER c omm a nds , t rans fer fi l es , an d th en en te r BYE c omm a nd s t o s a f e gu ard their f i Le.s , For t h is mode t he BY E c o mm an d sh o ul d no t c l os e t he TEL NET c o n n ec ~ i o n . In fa c t , this i s he de f in i t i on of t he BYE co m man d i f ente r 2d dur i ng a tr ans f er an d i f a ne w USER c o mm a nd c om e s be f or e t he r an .s fe r is iom p l e t e . To e H rn f. n at e : he t i mi ng un c e rt a i n t i t i e s of t he BYE co mm a nd , an d a l so to a I Low th e "ho t c ar d rea de r " mode , it is re commen ded tha t t he BYE c o mm a nd be r e de fin e d to mean " t e rmi na t e t he c ur r e n tl y a c t i ve us e r an d req u ir e a ne w USE R c o mm a nd be fo r e ad di t i on a l. t r a n s fe rs . " The TELNET c onne c t i on s c )u l d f cou r s e be c l os e d by t h ~ t s e r" pr o ce s s a s s oon a s t he BYE co mma nd i s ackn ow l.e dg ed . For sc r p ro c e s s e s t ha t c a nno t or do no t choo s e to do this, a new comm a nd CLSE sh ou l d be a dde d , t o ha ve t he me a ni ng o f "c l o s e the TEUiliT c onne c t io n when pos s i b le ( Le. , aft er a ny acti ve t r a ns f e r i s comp le t e ). " Thus BYE wou l d h ave on l y th e mean i ng i t c ur r e n t l y do es if e n t e r ed d ur ing ? n a c t iv e t r an s f er , an d CLSE wou ld ha ve th e cu r r e n t me ani ng of BYE i n o t he r c i r c um s t a n ce s . Fu rth er sugge s t i o .s wou Ld be t ha t CLSE i mp l i e s a BYE an d t ha - a e LSE d ur in g a n aC l.ive t r a ns f e r " l og i c a ll y " clo s e s th e conne c t i on i mm ed i a t e l y (L e. , r:. o co mm a nd s may be c t e r e d whi l e wa i t i n g fo r th e tra n sf e t o c omple te ) . Some s mall i t ems missing fr om t he p r o t o c o l a r e 11m·1 me n t i one d . \ \
Page 10: RF C 41 8 Pa ge 10 DEFAULT PA RANETER VALUES I t sh ou l d be more emp ha t i c ally s t a t ed t h at se rv e r s mus t a ss ume de f a ult v alue f o r a ll unspe c i fi e d par ' e t er s (Ha DE, TYPE, e t c.). Hi th o u t th i s, a ll us e r pr oc e s s e s mu st a l wa y s se nd 11 c mp l.e t e se t o f pa r ame ter spe c i f i c a ti on c omm a nd s, s i nc e sone s e rver s omeHhe r e ma y no t ma ke t he cor r ect d ef a ul t a s sump t i ons . Th is is obv i ou sly unde s i r a b l e . SY CH ON THE TElN ET CO NNECTI ON The pr o t oc ol s t tes t ha t t he AB O. c o m:n a n d s houl d be pr e ce de d by t he Te ln e t SYNCII co nd i t i on , for reas ons o f e ff i c i e nc y ( so t ha t s e rv e r s do no t need t o be con tin ua lly che ck i ng t he Tel ne t co nn ect i on d urin g a t r a n s f e r) . Thi s sh ould be ex t e n ded t o o t he r c onmands wh i ch may be u s e d dur i ng a t r ns f er ( BYE , USER, STA T, e t c . ) . BREAK a THE '.i.'El NET C Ol~ r E C T ON1 The qu es t io n o f vha t a BREfX c ha r a ct e r m e a ~ s ov er th e Te l ne t co n n ect ion is no t to u ch ed . Eve n i f t he BRE AK i s t o h2ve no fu nc t i on th i s sh ou l d be s pe c i fi e d . I n the TSS i plemen t a t i on , t he onl y t i me a BRE AK is re c o gn i ze d i s dur i ng a HAI L c ommand ; the BREA K will a bor t t he c omm a nd and c a nce 1 t he ma i l , CATCH- ALL REP LY CODES It i s fe l t t ha t on e re p ly c ode of e a ch t ype should be a s s i gne d t he me a n i n g of "ot r." r " s o th a t s y s t em- de p en d e n t c" en t s co ul d be pro pe r l y id e n ti fi e d. For ex amp l e , if a n i.nd e x ed f i l e i s b ein g s e n t to TSS a nd r e co r d u a r e re cei ve d lIt o f or der , t he rep l y cod e c u r r en t ly use d i s 453 , al t hou gh t h i s i.s s u ppos e d to mean " i n s uf f i ci e n t s p ac e . II If a c atch- a l l c o de we r c de f i ned , t he me ss age t ex t coul d be us e d t o f u r t he r s e c i fy th e ex a c t me an i ng . PARAMETER VAL LDATI ON Cer t - i n s e r ve r pr oc e s se s ( no t a b l y TENEX ) ha ve a p pa r en t l y d ivi d ed t he fi l e t r a ns f e r c o mm a nd s i nt o t HO lo gica l gr o ups : pa r ame t e r s e tti ng c omma nds an d fi le man i l' ulation c o mm a nd s . The pa r amete r se tt i ng c omm a nd s ar e TYPE, }10 DE, STRU, a nd BYTE . The parame e r va l ue s sp e c if i e d on these c o mm a nds \ a r e no t va l id a t ed Hhen re ce iv e d ; th e y are s i mpl y st or e d an d a r ep ly c ode 200 i r e t u r ne d . The pa raI:leters are va li da t e d on t he ne x t f i l e ma n ip u \ l a ti on c omman d , hOHever , with e rr or s r e s u l ti ng in c a nc e l la t i on o f th e f i l.e man ip u l a t ion c omman d i t s e If , .;r i t h r e p l y c ode 50 3 . I am awar e o f th e pr ob l ems wi .t h va l i da t in g pa r am t.e r s whe n r e c eiv e d ( L e . , o f t empor a r i l y pr oduc i ng i nva li d c omb i n at i on s whe n ch a ng i ng f r om one val i d s et to an ot he r ) but i t i s felt th a t some s t a nda r d c ou l d be se t up t o a ll oH t hi s . As an a hs o l u t e mi n imum, t o t a l l y i nv al i d or un supp or t e d param e t e r va l ue s s hou ld be d iagnose d Lntm cd i.a t e l y ( e . g . , Ha DE 13 if BLOCK mod e i s no t i mp l eme nt e d) . Th is prob le m i s a nu i s anc e w itl: a h um an us e r , b ut it be c om e s q uit e s e r ious wi t h a u s e r a u t oma t o n: t he amoun t of wo rk ne c e ss a ry f or an a ut omat on t o emp ir i ca ll y de t e rm in e a v ali d se t o f par ame t e r s i s in t o l e r ab le .