Designing and Deploying Multilink PPP over Frame Relay and ATM

C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M Designing and Deploying Multilink P P P ov er F r am e R elay and A T M TAC Notice: What's C han g i n g o n T A C We b H el p u s h el p y ou Contents Introduction P re re q uis ite s R e q u ire m e n ts C o m p o n e n ts U s e d C o n v e n tio n s D e s ig n D a ta L in k O v e rh e a d V o IP B a n d w id th R e q u O p tim iz e F g m e n ta tio T ffic S h a p in g a n d P o H ints a nd C a v e a ts C a s e S tudy In tro d u c tio n N e tw o rk O v e rv ie w C o n fig u tio n s N e tP ro D is cus s ion F orum R e l a te d Inf orm a tion P a g e o f 21 Please rate this d o c u m en t Excellent G o o d A v er a g e F a ir P o o r T his d o c u m en t so lv ed m y p ro b lem ire m e n ts n S iz e lic in g C o n s id e tio n s Y es N o J u s t b r o w s i ng S u g g estio n s f o r im p ro v em en t: s - F e a ture d C onv e rs a tions ( ch a r a cter li m i t) Send I ntr od u c ti on M u ltilin k P P P o v e r A T M a n d M in tro d u c e d in C is c o IO S ® S o ftw R e l a y / A T M i n t e r w o r k i n g (F R / A W A N lin k s P rio r to th is fe a tu re s u p p o rte d b y C is c o IO S o n b o th L a y e r 3f r a g m e n ta tio n u ltilin k P P P a re R e le a s e T M IW ) th a , th e re w a s n A T M a n d F o v e r F m e R e 12 1(5) T T h i s t d e p lo y V o ic e o c o m m o n L a y m e R e la y c u s l a y (M fe a tu re o v e r IP e r 2f r a to m e rs L P o A T M a n d is ta rg e te d a t (V o I P ) a c r o s g m e n ta tio n s c w ith F R /A T M M L P o F R c u s to m e r s m e d iu m h e m e th a IW w e r ) w a s s w ith F m e to lo w s p e e d t w a s e fo rc e d to d o P r er eq u i si tes Requirements T h is d o c u m e n t is in te n d e d fo r n e tw o rk in g p e rs o n n e l in v o lv e d in th e d e s ig n a n d d e p lo y m e n t o f V o IP n e tw o rk s th a t in v o lv e M L P o A T M a n d F m e R e la y n e tw o rk s C is c o re c o m m e n d s th a t y o u h a v e k n o w le d g e o f th e s e to p ic s : h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M
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F m e R e la y /A T M
V o i c e Q u a l i t y o f S e r v i c e (Q o S ) C o n f i g u r a t i o n P a g e o f 21 in te rw o rk in g T h is d o c u m e n t is n o t in te n d e d to p ro v id e te c h n o lo g y tra in in g o n th e s e s u b je c ts A lis t o f re fe re n c e m a te ria ls is in c lu d e d a t th e e n d o f th is d o c u m e n t C is c o re c o m m e n d s th a t y o u re v ie w a n d u n d e rs ta n d th e s e d o c u m e n ts p rio r to re a d in g th is d o c u m e n t:

V o I P o v e r F r a m e R e l a y w i t h Q u a l i t y o f S e r v i c e (F r a g m e n t a t i o n , T r a f f i c S h a p i n g , L L Q / I P R T P P rio rity ) V o IP Q o S fo r F m e R e la y to A T M In te rw o rk in g w ith L L Q , P P P L F I a n d c R T P C o mp o nents U sed T h e in fo rm a tio n in th is d o c u m e n t is b a s e d o n th e s e s o ftw a re a n d h a rd w a re v e rs io n s :



C i s c o I O S S o f t w a r e R e l e a s e 12 1(5) T o r l a t e r f o r M L P o v e r F R / A T M IW C i s c o I O S S o f t w a r e R e l e a s e 12 2(2) T o r l a t e r f o r C o m p r e s s e d R e a l T i m e T r a n s p o r t P r o t o c o l (c R T P ) o v e r A T M C i s c o I O S S o f t w a r e R e l e a s e 12 0(7) T f o r L o w L a t e n c y Q u e u e i n g (L L Q ) o v e r F r a m e R e l a y a n d A T M o n th e P h y s ic a l In te rfa c e C i s c o I O S S o f t w a r e R e l e a s e 12 1(2) T f o r L L Q o v e r F r a m e R e l a y a n d A T M c i r c u i t (P V C ) p e r p e rm a n e n t v irtu a l T h e c a s e s tu d y in c lu d e d in th is d o c u m e n t is b a s e d o n a p ro d u c tio n n e tw o rk th a t u s e s th e s e s o ftw a re a n d h a rd w a re v e rs io n s :
T h e c o r e C i s c o 3660 r o u t e r s r u n C i s c o I O S S o f t w a r e R e l e a s e 12 2(5 8) T T h e r e q u i r e m e n t f o r c R T P o v e r A T M d i c t a t e s t h e u s e o f C i s c o I O S S o f t w a r e R e l e a s e 12 2T T h i s k n o w n i s s u e i s r e s o l v e d i n C i s c o I O S S o f t w a r e R e l e a s e 12 2(8) T 1: C i s c o b u g I D C S C d w 44216 ( r e g i s t e r e d c u s t o m e r s o n l y ) - c R T P c a u s e s h i g h C P U w h e n t h e c l a s s b a s e d w e i g h t e d f a i r q u e u e i n g (C B W F Q ) / L L Q l i n k r e a c h e s c o n g e s t i o n
T h e b R e le a is trig IO S S r a n c h C i s c o 2620 r o u t e r s s e 12 2(3) t o o n e 2(6a ) g e r e d b y a g a t e w a y -r e l a t e o f t w a r e R e l e a s e 12 2(3) d a re in T h e C d is s u o e s n th is e o t e p ro c e ss o f b e c o 2620s a l s o a A s fa r a s th e W e x h ib it a n y s ig in g u p g d c t a s b n c A N a n d Q n ific a n t is s e d fro m C is c o IO S S o ftw a re h H 323 g a t e w a y s T h e u p g r a d e o S fe a tu re s a re c o n c e rn e d , C is c o u e s h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e o f 21 C o nv entio ns R e fe r to C is c o T e c h n ic a l T ip s C o n v e n tio n s fo r m o re in fo rm a tio n o n d o c u m e n t c o n v e n tio n s D esi g n T h is s e c tio n d is c u s s e s s e v e l d e s ig n c o n c e p ts re la te d to th e d e s ig n a n d d e p lo y m e n t o f M u ltilin k P P P o v e r F m e R e la y a n d A T M D a ta L ink O v erh ea d W h e n o v e rh e d e te rm n u m b e w a s te d th e s e f y o u a d in e r o f o n a c to d e s ig n A T M O v e rh e a d in th e o p tim u m A T M c e lls , c e ll p a d d in g rs: flu M e s T a n d F m e n c e s th L P fra g p e c ia lly h e d a ta e R e la y n e tw o rk s w ith e a m o u n t o f b a n d w id th m e n t s iz e It is c ritic a l o n s lo w s p e e d P V C s w lin k o v e rh e a d o n M L P M L P , y o u m u s t u n d e rs ta c o n su m e d b y e a c h V o IP to o p tim iz e th e fra g m e n t h e re a s ig n ific a n t a m o u n o v e r F m e R e la y a n d A
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T h e d i r e c t i o n o f t h e t r a f f i c (A T M
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T h e tra ffic ty p e D a ta p a c k e ts h a v e a n M L P h e a d e r; V o IP p a c k e ts d o n o t n d th e d a ta lin k c a ll It a ls o h e lp s s iz e to fit a n in te g l t o f b a n d w id th is T M P V C s d e p e n d s o n d e v i c e (t r a n s p a r e n t o r t r a n s l a t i o n a l ) to F m e R e la y o r F m e R e la y to A T M ) a n d F m e R e la y le g s o f th e P V C T h is ta b le s h o w s th e d a ta lin k o v e rh e a d fo r a d a ta p a c k e t It d e ta ils th e n u m b e r o f b y te s in th e v a rio u s F r a m e R e la y , A T M , L L C , P P P , a n d M L P h e a d e r s f o r a ll p e r m u ta tio n s o f th e F R F 8m o d e o f o p e r a tio n , tra ffic d ire c tio n , a n d P V C le g F R F M ode T f f ic dire ction T ns p a re nt F m e R e l a y to A T M A T M to F m e R e l a y F m e R e la y A T M A T M L L C D S A P /S S A P (0 x fe fe ) F m e R e l a y or A T M l e g of P V C F m e F l a g (0 x e ) F m e R e l a y h e a de r T ns l a tion F m e R e l a y to A T M A T M to F m e R e l a y F m e R e la y F m e R e la y A T M A T M F m e R e la y 1 0 0 2 0 2 2 L L C C ontrol h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M 1 1 1 1 1 1 1 1 2 2 2 2 4 4 4 4 P rotocol F irs t m e nt ) 2 2 2 0 0 0 0 8 0 8 0 2 0 15 18 20 17 15 20 20 15 (0 x ) N L P ID ( x cf f or P P P ) M L P P rotocol ID ( x 0 d) M L P S e q ue nce num b e r P P P ID ( f g onl y P a y l oa d ( L a y e r3 + ) A T M A da p ta tion L a y e r( A A L ) F m e C h e ck S e q ue nce (F C S ) T ota l O v e rh e a d ( b y te s ) P a g e o f 21 1D S A P / S S A P —D e s t i n a t i o n S e r v i c e A c c e s s P o i n t / S o u r c e S e r v i c e A c c e s s P o i n t 2N L P ID —N e t w o r k L a y e r P r o t o c o l I d e n t i f i c a t i o n T h e is b e fra m M L P tra n c a u e fo o A s la se rm T M tio n a th e F a t is in b l P V C is R F 8d e v M L P o F R o th d ire c T h e tra n s p a re n t P V C c o m p le x ity a ris e s b e c a rrie d a c ro s s b y th e M L P o A T M fo rm a t T h e re fo re , th e re s u lt th e e a s ie s t to c o m p re h e n d a s th e o v e rh e a d is th e s a m e in b o th d ire c tio n s T h is ic e tra n s la te s b e tw e e n th e M L P o A T M a n d M L P o F R fo rm a ts A s a re s u lt, th e o n th e F m e R e la y le g in b o th d ire c tio n s T h e fo rm a t o n th e A T M le g is tio n s is s lig h tly m e s s c a u s e th e F m e IW d e v ic e o n to T h is fo rm a t is c a is d iffe re n t fra m ie r b e c R e la y th e A T rrie d a e fo rm a u s e th e o v e ro u te r s e n d s M s id e S im c ro s s b y th e a ts in th e tw rh e a d p a c k ila rly IW d o d ire d iffe rs in th e e ts in th e M L P , th e A T M ro u e v ic e o n to th e c tio n s o n e a c h tw o d ire o F R fo r te r s e n d F m e R le g c tio n m a t s p a c e la y s T h T h is k e ts s id e is fo rm a t is in th e I n c o m p a r i s o n , t h e o v e r h e a d o n a n e n d -t o -e n d F r a m e R e l a y P V C t h a t u s e s F R F 12 i s 11 b y t e s T h e r e f o r e , o n a n e n d -t o -e n d F r a m e R e l a y l i n k , F R F 12 i s a m o r e e f f i c i e n t c h o i c e f o r l i n k f r a g m e n t a t i o n h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M a n d in te rle a v in g s in c e th e re is n o to h ig h s p e e d T d ig ita l s u b s c rib e (L F s ta n h e re r lin P a g e o f 21 I ) t h a n M L P O n e n d -t o -e n d A T M v i r t u a l c i r c u i t s (V C s ) , M L P i s t h e o n l y c h o i c e d a r d s -b a s e d f r a g m e n t a t i o n a v a i l a b l e H o w e v e r , e n d -t o -e n d A T M V C s a r e m e d i u m fo re , L F I is n o t re q u ire d T h e e x c e p tio n to th is ru le is s lo w s p e e d A T M V C s o v e r e (D S L ) T h e P P P ID is p re s e n t in th e firs t M L P fra g m e n t o n ly T h e re fo re , th e o v e rh e a d in th e firs t fra g m e n t is a lw a y s tw o b y te s m o re th a n in s u b s e q u e n t fra g m e n ts T h e ta b le h e re s h o w s th v a rio u s F m e R e la y , A tra ffic d ire c tio n , a n d P V p a c k e ts a re s e n t a s P P P s c e n a rio F R F M ode T f f ic dire ction F m e R e l a y or A T M l e g of P V C F m e F l a g (0 x e ) F m e R e l a y H e a de r L L C D S A P /S S A P (0 x fe fe ) L L C C ontrol (0 x ) N L P ID ( x cf f or P P P ) P P P ID a ta , L le g c k e lin k o v L C , a n T h e m ts a n d n e rh d P a in o t e a d P P d if a s M fo r a h e a d e fe re n c L P p V o rs f e b a c k IP p a c k e t It d o r a ll p e rm u ta e tw e e n a d a ta e ts A ll o th e r T ns p a re nt e ta ils tio n s a n d a a sp e c th o f V ts e n u m th e F o IP p a re id T ns l a tion F m e R e l a y to A T M A T M to F m e R e l a y F m e R e la y A T M A T M b e r o f b y te s R F 8m o d e o a c k e t is th a t e n tic a l to th e F m R e la to F m R e la F m e R e l a y to A T M A T M to F m e R e l a y F m e R e la y F m e R e la y A T M A T M F m e R e la y 1 0 1 0 2 0 2 0 2 2 0 1 1 1 1 1 1 1 1 1 2 2 2 2 0 0 0 0 8 0 8 0 P a y l oa d ( IP + U s e r D a ta g m P rotocol (U D P ) + R T P + V oice ) A A L e d T M C p a in th e f o p e tio n , V o IP d a ta e y y e h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M F C S T ota l O v e rh e a d ( b y te s ) P a g e o f 21 0 2 0 2 12 14 11 14 14 I n c o m p a r i s o n , t h e d a t a l i n k o v e r h e a d f o r a V o I P p a c k e t o n a n e n d -t o -e n d F r a m e R e l a y P V C i s s h o w n i n th e fa r rig h t c o lu m n V o I P B a nd w id th Requirements W h e n y o u p ro c a lc u la tio n s T b a s e d o n th e c c R T P (f o r e x a c o m p re sse d fr v is io n b a n d w id th fo r V o IP , h is ta b le s h o w s th e p e r c a ll h a c te ris tic s o f th e P V C T m p le , n o U D P c h e c k s u m a n o m 40 b y t e s t o b y t e s F R F M ode e a ta lin k o v e rh e a d m u s w id th re q u ire m e n ts fo lc u la tio n s in th is ta b le tr a n s m is s io n e r r o r s ) H T ns p a re nt T f f ic F m e R e l a y dire ction to A T M F m R e la y A T M of P V th e d b a n d h e c a d n o T ns l a tion A T M to F m e R e l a y F m e R e l a y to A T M A T M to F m e R e l a y c lu d e a rio u e a b s a re A T M F m e R e la y F m e R e la y A T M A T M F m e R e la y 27 42 42 28 27 42 42 27 26 12 21 21 13 12 21 21 12 11 G m s S a m p le s -N o cR T P 20 28 28 21 20 28 28 20 20 G m s S a m p le s 10 14 14 11 10 14 14 10 10 G m s S a m p le s -N o cR T P G m s S a m p le s - cR T P d in th e b a n d s fla v o rs o f V e s t -c a s e s c e n th e n c o n s is te w id th o IP It is a rio fo r n tly F m e R e la y to F m e R e la y A T M C or F m e le g R e la y t b e in r th e v a ssu m e a d e r h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e o f 21 - cR T P G 1 m s S a m p le s -N o cR T P G 1 m s S a m p le s - cR T P G 1 m s S a m p le s -N o cR T P G 1 m s S a m p le s - cR T P B e c a u se s c e n a rio tra n s p a r o n e d ire K b p s p e In c o m th e fa r e n c a p s T h e re f F m e th e F o e n t c tio r c a 83 106 106 84 83 106 106 83 82 68 84 84 69 68 84 84 68 67 76 97 97 76 76 97 97 76 75 66 84 84 66 66 84 84 66 65 C , it is (m s e c ) a rio o n s to b e n e c e s sa m p th e F d o n e o v r e P V n a ll p a ris o n rig h t c o u la tio n o re , F R e la y V e rh e a d v a x a m p le , c C T h e b a n d 13 K rie s o n th e d iffe re n o n s i d e r G 729 w i t h n d w id th re q u ire m e b p s in th e o th e r P r , th e V o IP b lu m n o f th e re s u lts in a n m e R e la y e n C N ote : c R T P o v e r A T M a n d w id th re a b o v e ta b le e x tra b a n d w c a p s u la tio n q u ire T h e id th w ith t le g s o f th 20 m i l l i s e n ts fo r th is o v is io n in g m e a d c o F R e P V c o n d sc e n n e e d n t o n a n e n d itio n a l o v n s u m p tio n F 12 m a k e d -t o -e n e rh e a d b e tw e e s m o re d F m o f P P P n K se n se sa ry lin g m e w ith e R c o m b p s th a n to a n R th e la y p a r a n d M L d e s i g n f o r t h e w o r s t -c a s e d c R T P a c ro ss a e l a y l e g i s 12 K b p s i n e a s s u m p t i o n o f 13 P V C e d to K P o n is a ls o s h o w n in n a tiv e F m e R e la y b p s p e r c a ll a n e n d -t o -e n d r e q u i r e s C i s c o I O S S o f t w a r e R e l e a s e 12 2(2) T o r l a t e r O p timiz e F g menta tio n S iz e T h e re a so n in to s m a lle fra g m e n ts c o n fig u re d fo rm u la to to u s e r c h u n k In C is c w ith th c a lc u la M L P o s T h e o IO S , e h e lp te th e a n a F m e R e la y /A T M P ro u te r th e n e x p e d ite s V o th e fra g m e n ta tio n s iz e is o f t h e p p p m ul til ink f p p ro p ria te fra g m e n t s iz e : V C IP n o g m is to a llo w p a c k e ts b y t c o n fig u re e nt-de l a y fo r la rg e d a in te rle a v in g d d ire c tly In c o m m a n d C ta p a c k e th e m in s te a d , th is c o IO S ts to b e b e tw e e e d e s ir th e n u fra g m e n te d n th e d a ta e d d e la y is s e s th is fragment size = delay x bandwidth/8 W h n u m p a d fra g e n y o u b e r o f d in g F m e n t d o c e o r T h M L P a c ro ss A lls If th is o p tim e x a m p le , if e a c e r e f o r e , 106 b y T M , th e iz a tio n h fra g m te s a re u fra is n e n t se d g m o t is to e n t s iz e d o n e , th 49 b y t e s c a rry a n e e d e b a n lo n g p a y lo s to b e d w id th , tw o A a d o f o o p tim iz e d s o th a t it fits in to a n in te g l re q u ire d c a n a lm o s t d o u b le d u e to T M c e lls a re re q u ire d to c a rry e a c h n l y 49 b y t e s h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M C is c o IO S a u to m a tic p e rfo rm s M L P o A T M th e n e x t in te g l n u m o p tim iz a tio n o n b o th M L P P V C c a n b e e n H o w e v e r, C is c o IO S e n d is A T M o r F m a lly o p tim iz e s th e fra g m e n t s iz e to u s e a n in te g l n u m b a n d M L P o F R C is c o IO S a u to m a tic a lly ro u n d s u p th e b e r o f A T M c e lls N o n e w C L I c o m m a n d s a re a d d e d C th e F m e R e la y a n d A T M e n d s o f a M L P o F R /A T M P d -t o -e n d F r a m e R e l a y I n t h i s c a s e , o p t i m i z i n g i t f o r A T o p tim iz e s th is s c e n a rio fo r A T M s in c e it h a s n o w a y to e R e la y P a g e o f 21 e r o f A T c a lc u la te is c o IO S V C It is M is n o t d e te c t w M c e lls w h e n d fra g m e n t s iz p e rfo rm s th is p o s s ib le th a t a re q u ire d h e th e r th e re m it e to n o te N ote : D u e t o r o u n d i n g , t h e d e l a y t h a t r e s u l t s c a n b e s l i g h t l y h i g h e r t h a n t h a t c o n f i g u r e d T h i s r o u n d i n g e r r o r i s m o r e s i g n i f i c a n t o n l o w -s p e e d P V C s Y o u c a n a ls o C is c o IO S , c a fra g m e n t s iz e D a ta L in k C o o v e rh e a d , th e se q u e n c e n u m c o n fig u lc u la te , a d ju s t n t r o l (H M L P c b e r, a n re o th e fo r D L o d e d th p tim iz a tio n m a n u a lly S in o p tim a l fra g m e n t s iz e a n d th e d a ta lin k o v e rh e a d , a s C ) a n d h a s 2b y te s o f d a ta in c lu d e s in its c a lc u la tio n e P P P ID a s o u tlin e d in th c e th e fra g m e n t s iz e c a n n o t b c o n v e rt it in to a d e la y W h e n th e M L P c o d e a s s u m e s th a t e lin k o v e rh e a d In a d d itio n to s th e 8b y te s m a d e u p o f th e M e firs t ta b le a b o v e e sp e y o u v e ry th e H L P c ifie d d ire c tly in c a lc u la te th e l i n k i s H i g h -L e v e l D L C d a ta lin k ID , th e M L P U s e th is p ro c e d u re in o rd e r to c a lc u la te th e d e la y to b e c o n fig u re d in C is c o IO S : C a lc u la te th e th e o re tic a l fra g m e n t s iz e b a s e d o n th e d e s ire d d e la y a n d th e b a n d w id th o f th e P V C : fragment = bandwidth * delay / M a k e s u r e t h a t t h e f r a g m e n t i s a m u l t i p l e o f 48 b y t e s , s o t h a t i t f i t s i n t o a n i n t e g r a l n u m b e r o f A T M c e lls T h e fo rm u la to c a lc u la te th e c e ll a lig n e d fra g m e n t s iz e is : fragment_ aligned = ( int( fragment/4 8) + ) * A d ju s t fo r th e d a ta lin k o v e rh e a d th a t is n o t ta k e n in to a c c o u n t b y M L P A s s e e n e a rlie r, th is o v e rh e a d d iffe rs b a s e d o n th e P V C c h a c te ris tic s C o n s id e r th e A T M s id e o f th e P V C a s th is is th e s id e fo r w h ic h y o u o p tim iz e T h is ta b le s h o w s th e n u m b e r o f b y te s o f d a ta lin k o v e rh e a d o n th e A T M s id e F R F M ode T f f ic D ire ction F m e R e l a y or A T M l e g of P V C L L C D S A P /S S A P (0 x fe fe ) T ns p a re nt T ns l a tion F m e A T M to F m e A T M to R e l a y to F m e R e l a y to F m e A T M R e la y A T M R e la y A T M A T M A T M A T M 2 h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M L L C C ontrol (0 x ) 1 1 N L P ID ( x cf f or P P P ) 1 1 A A L 8 8 N on M L P ov e rh e a d ( b y te s ) 10 12 12 12 P a g e o f 21 T o a rriv e a t th e fra g m e n t s iz e o n w h ic h M L P b a s e s its c a lc u la tio n s , s u b tra c t th e d a ta lin k o v e rh e a d f r o m t h e d e s i r e d c e l l -a l i g n e d f r a g m e n t s i z e A d d b a c k b y t e s i n o r d e r t o c o m p e n s a t e f o r t h e H D L C e n c a p s u la tio n th a t M L P a lw a y s a s s u m e s T h e fo rm u la to c a lc u la te th e fra g m e n t s iz e th a t th e M L P c o d e ta rg e ts is : fragment_ mlp = fragment_ aligned - datalink _ o v erhead + C o n v e rt th e fra g m e n t s iz e th a t re s u lts in to th e c o rre s p o n d in g d e la y w ith th is fo rm u la : delay = fragment_ mlp /bandwidth x 8bits/byte In m o s t c a s e s , th e d e la y c a lc u la te d is n o t a n in te g l n u m b e r o f m illis e c o n d s S in c e C is c o IO S o n ly a c c e p ts a n in te g e r v a lu e , y o u m u s t ro u n d d o w n T h e re fo re , th e d e la y v a lu e y o u c o n fig u re in C i s c o I O S w i t h t h e h e l p o f t h e p p p m ul til ink f g m e nt-de l a y c o m m a n d i s : fragment_ delay = int( fragment_ mlp /bandwidth x 8bits/byte) In o rd e r to c o m p e n s a te fo r th e a b o v e ro u n d in g e rro r, fu d g e th e b a n d w id th u s e d b y M L P to c o n v e rt fro m d e la y to fra g m e n t T h e fu d g e d b a n d w id th th a t y o u c o n fig u re in th e C is c o IO S w ith th e h e lp o f t h e b a ndw idth c o m m a n d i s : bandwidth = fragment_ mlp /fragment_ delay * T h is ta b le s h o w s c o m m o n P V C sp c a lc u la tio n s d o n d ire c tio n s T h e m d e s ig n in g fo r th e e n c o u n te re d d u e n u m b e r o f c e lls P V C S p e e d (K b p s) t h e o p t i m a l v a l u e s o f p p p m ul til ink f g m e nt-de l a y a n d b a ndw idth f o r t h e m e e d s A t a r g e t d e l a y o f 10 m s e c i s a s s u m e d I n o r d e r t o s i m p l i f y t h e t a b l e , t h e o t d iffe re n tia te b e tw e e n tra n s p a re n t a n d tra n s la tio n a l P V C , o r b e tw e e n tra ffic a x im u m d if f e r e n c e in d a ta lin k o v e r h e a d is o n ly 2b y te s T h e r e f o r e , th e p e n a lty w o r s t c a s e o f 12 b y t e s i s s m a l l A l s o s h o w n i n t h e t a b l e i s t h e " r e a l " d e l a y t h a t to th e fa c t th a t y o u in c re a s e th e fra g m e n t s iz e s o th a t fra g m e n ts fit in to a n in te g F g m e nt S iz e ( ce l l s ) p p p m ul ti-l ink f g m e ntde l a y ( m s e c) B a ndw idth (K b p s) o st is fo r l R e a l D e la y ( m s e c) h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M 56 12 57 13 128 11 132 12 64 192 256 320 384 11 448 12 512 14 576 16 640 17 704 19 768 21 10 11 10 10 10 10 10 10 10 10 10 68 202 260 337 414 452 529 606 644 721 798 P a g e 10 o f 21 12 12 10 10 11 10 10 10 10 10 10 T f f ic S h a p ing a nd P o l ic ing C o nsid era tio ns S p e c ia l c o n s id e tio n is g iv e n to tra ffic s h a p in g a n d p o lic in g in a F m e R e la y /A T M IW e n v iro n m e n t T h e is s u e s in th e F m e R e la y to A T M d ire c tio n a re d iffe re n t to th e is s u e s in th e A T M to F m e R e la y d ire c tio n T h e re fo re , e a c h to p ic is d e s c rib e d s e p a te ly T h e m a in is s u e in th e F m e R e la y to A T M d ire c tio n is th e p o te n tia l e x p a n s io n in b a n d w c o n s u m p t i o n w h e n g o i n g f r o m f r a m e t o c e l l F o r e x a m p l e , a 49 b y t e f r a m e o n t h e F r a m e c o n s u m e s t w o c e l l s , o r 106 b y t e s , o n t h e A T M s i d e T h e r e f o r e , i t c a n n o t b e a s s u m e d t h a c e l l r a t e (S C R ) e q u a l s t h e c o m m i t t e d i n f o r m a t i o n r a t e (C I R ) T h e w o r s t c a s e s c e n a r i o o c F r a m e R e l a y f r a m e c o n t a i n s b y t e o f p a y l o a d E a c h o f t h e s e b y t e s c o n s u m e s a f u l l 53 b A T M s id e A s a n e x a m p le o f th is c o n c e p t, th is e x tre m e a n d u n re a lis tic s c e n a rio d ic ta te s 53 t i m e s t h e C I R T w o m o r e r e a l i s t i c e x a m p l e s a r e :

id th R e la y s id t th e s u s ta c u rs w h e n y te c e ll o n a n S C R th e in a b le e a c h th e a t is A G 729 V o I P p a c k e t i s 60 b y t e s l o n g , o r 69 b y t e s (w h e n M L P a n d F r a m e R e l a y o v e r h e a d a r e i n c l u d e d ) O n t h e A T M l e g , i t c o n s u m e s t w o c e l l s o r 106 b y t e s T h e r e f o r e , i f a l l t r a f f i c c a r r i e d i s V o I P , t h e n a n a p p r o p r i a t e m a p p i n g i s S C R = 106/ 69 = x C I R A T e l n e t p a c k e t t h a t c a r r i e s a s i n g l e k e y s t r o k e c o n t a i n s 40 b y t e s o f T C P / I P h e a d e r a n d b y t e o f d a t a O n t h e F r a m e R e l a y s i d e , t h i s t o t a l s 56 b y t e s , i n c l u d i n g o v e r h e a d H o w e v e r , o n t h e A T M s i d e t h i s p a c k e t e x p a n d s t o t w o c e l l s I n t h i s c a s e , S C R = 106/ 56 = x C I R A p p e n d ix A , d e s c r ib d e riv e S C R th e n u m b e r re a l n e tw o r e x is tin g A T w ith y o u r c c a rrie r, th is o f t h e A T M F o r u m s t a n d a r d , BISDN Inter Carrier Interface ( B-ICI) Sp ecificatio n V ers io n e s tw o m e th o d s o f m a p p in g b e tw e e n S C R a n d C IR W h ile b o th p ro v id e a s c ie n tific w a y to fro m C IR , n e ith e r o n e is a n y m o re a c c u te th a n th e d a ta to w h ic h th e y a re a p p lie d O n e o f s re q u ire d b y th e fo rm u la s is th e ty p ic a l fra m e s iz e , a n u m b e r th a t is h a rd to d e te rm in e in a k A ls o , a n u m b e r th a t c a n p o te n tia lly c h a n g e a s n e w a p p lic a tio n s a re ro lle d o u t o n a n M /F m e R e la y n e tw o rk T h e b e s t re c o m m e n d a tio n to s o lv e th is p ro b le m is to w o rk c lo s e ly a rrie r s in c e th e ir p o lic in g p o lic y w ill b e o f c ritic a l im p o rta n c e W ith th e a s s is ta n c e o f th e f a i l -s a f e a p p r o a c h i s p o s s i b l e : h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M

P a g e 11 o f 21 F m e R e l a y to A T M D ire ction - I n t h e F r a m e R e l a y t o A T M d i r e c t i o n , t h e c a r r i e r n e e d s t o p o lic e tra ffic in b o u n d a t th e F m e R e la y in g re s s p o in t o n ly F o r in s ta n c e , o n th e F m e R e la y s w i t c h c o n n e c t e d t o t h e F r a m e R e l a y a t t a c h e d c u s t o m e r p r e m i s e s e q u i p m e n t (C P E ) d e v i c e , t h e c a rrie r p o lic e s tra ffic a c c o rd in g to th e c o n tra c te d C IR T h is p o lic in g p o lic y is illu s tra te d in th e fig u re h e re N o fu rth e r p o lic in g s h o u ld h a p p e n o n c e tra ffic is a llo w e d in to th e n e tw o rk a t th e in g re s s p o in t T h e im p lic a tio n o f th is p o lic in g p o lic y is th a t d a ta re c e iv e d o n th e F m e R e la y s id e is a llo w e d to e x p a n d a n d c o n s u m e w h a te v e r b a n d w id th is re q u ire d to a llo w fo r c e ll ta x , A A L o v e rh e a d , a n d p a d d in g in o rd e r to c a rry it a c ro s s th e A T M le g o f th e n e tw o rk In m o s t c a s e s , th e A T M b a n d w id th re q u ire d is le s s th a n tw ic e th e F m e R e la y b a n d w id th u s e d A T M to F m e R e l a y D ire ction - I n t h e A T M t o F r a m e R e l a y d i r e c t i o n , t h e o p p o s i t e i s e x p e rie n c e d B a n d w id th u s a g e is re d u c e d w h e n g o in g fro m A T M to fra m e a s c e ll ta x , A A o v e rh e a d , a n d w h e n p a d d in g is re m o v e d H o w e v e r, b e c a u s e th e p o te n tia l tra n s m it te o f A T M s id e is m u c h h ig h e r th a n th a t o f th e F m e R e la y lin k , s e ttin g u p th e tra ffic s h a p in g c o rre c tly o n th e A T M ro u te r is c ritic a l fo r th e in te g rity o f v o ic e If th e s h a p in g is to o lo o s th e A T M ro u te r fe e d s d a ta a t a te fa s te r th a n th e p h y s ic a l s p e e d o f th e F m e R e la y lin k o th e r e n d A s a r e s u lt, p a c k e ts s ta r t q u e u in g u p o n th e F R F 8s w itc h A t s o m e p o in t, p a c k to d ro p a n d s in c e th e A T M /F m e R e la y n e tw o rk s d o n o t d is tin g u is h b e tw e e n v o ic e a n d V o IP p a c k e ts a re a ls o d ro p p e d A t th e s a m e tim e , if s h a p in g is to o re s tric tiv e , th e n th ro u A A L o v e r h e a d a n d p a d d in g is r e m o v e d b y th e F R F 8d e th e F m e R e la y lin k T h e re fo re , y o u c a n o v e rs u b s c rib e a m o u n t o f p a d d in g a n d A A L o v e rh e a d v a rie s d e p e n d in g a g g re s s iv e th e fra g m e n ta tio n is B e c a u s e y o u c a n n o t a c c b e tte r o ff n o t try in g to o p tim iz e fo r it O n th e o th e r h a n d g h p u t su ffe rs B e c a u se o f A v ic e It d o e s n o t c o n s u m e b th e A T M s id e o f th e P V C s o n a v e g e fra m e s iz e s a n d u te ly q u a lify th is o v e rh e a , c e ll ta x is c o m p le te ly d e te L th e e , th e n a t th e e ts s ta rt d a ta , T M c e ll a n d w id th lig h tly T h o w d , y o u a r rm in is tic h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = e ta x , o n h e It is 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e 12 o f 21 b y t e s f o r e v e r y 48 b y t e s o f p a y l o a d Y o u c a n o p t i m i z e f o r c e l l t a x b y s e t t i n g t h e s h a p i n g t a r g e t o n t h e A T M r o u t e r t o 53/ 48 x S C R T h e p o l i c i n g o n t h e c a r r i e r s i d e m u s t b e s e t t o a l l o w f o r t h i s s lig h t o v e rs u b s c rip tio n H i nts a nd Ca v ea ts



M L P o A T M / F r a m e R e l a y i s c u r r e n t l y o n l y t e s t e d a n d s u p p o r t e d w i t h a s e r v i c e -p o l i c y a t t a c h e d t o e i t h e r t h e v i r t u a l -t e m p l a t e o r d i a l e r -i n t e r f a c e s O m i t t i n g t h e s e r v i c e -p o l i c y c a n c a u s e t h e f e a t u r e t o n o t w o r k O n e e x a m p l e o f t h i s i s d o c u m e n t e d i n C i s c o b u g I D C S C d u 19313 ( r e g i s t e r e d c u s t o m e r s o n ly ) M L P o A T M /F m e R e la y c lo re p re s e n ts th e P P P lin k T h e is u s e d to te ll w h ic h is w h ic h P P P O F R c irc u its in to o n e b u th e P P P O F R d riv e r d o e s n o t lo a d b a la n c in g o v e r A T M o r lo a d b a la n c in g o v e r p h y s ic a l

te rfa c e s fo r e a c h P V C O n e o f th e s e b u n d l e T h e s h ow p p p m ul til ink c o m m p e r b u n d le is n o t s u p p o rte d P u ttin g tw o a d b a la n c e d w e ll a c ro s s th e c irc u its , s in c s ig n a lin g th a t re a l s e ria l d riv e rs d o M L P w n o tic e a b ly le s s e ffe c tiv e n e s s th a n th e s a m e a n d P P e W h e n y o u a p p l y a s e rv ice -p ol icy c o m m a n d t o a v i r t u a l -t e m p l a t e , C i s c o I O S d i s p l a y s t h i s n o r m a l w a rn in g m e s s a g e : T h e se m e s P P P v irtu a o n th e M L inte rf a ce s q u e u in g m
in L P k s lo o l E a c h P V C is a s s o c ia te d w ith fo u r d iffe re n t in te rfa c e s , n a m e ly th e p h y s ic a l in te rfa c e , th e s u b i n t e r f a c e , a n d t w o v i r t u a l -a c c e s s i n t e r f a c e s O n l y t h e M L P v i r t u a l -a c c e s s i n t e r f a c e h a s f a n c y q u e u i n g e n a b l e d T h e o t h e r t h r e e i n t e r f a c e s m u s t h a v e f i r s t i n , f i r s t o u t (F I F O ) q u e u i n g c r7 0 ( c r7 0 ( C las s B N o te C B
n e s t w o v i r t u a l -a c c e s s o th e r re p re s e n ts th e M M u ltip le P P P o F R lin n d le tra ffic w ill n o t b e p ro v id e th e flo w c o n tr fra m e re la y m ig h t s h o in te rfa c e c o nfig) # interface virtual-tem p late c o nfig-if) # s ervice-p o licy o utp ut G ro m it as ed W eig h ted F air Q ueueing ( C B W F Q ) no t s up p o rted W F Q s up p o rted o n M L P b und le interface o nly sa g e s a re n o rm l -a c c e s s i n t e r f P b u n d le v irtu v irtua l -a cce s e c h a n is m a l T h e a c e T h e a l -a c c e s s , s h ow firs t m e se c o n d s in te rfa q ue ue ss m c e a n a g e a d v e ssa g e T h is f d s h ow is c o a c p e s th a t n firm s t is v e r ol icy -m o n interface V irtual a s e r v i c e -p o l i c y i s n o t h a t t h e s e r v i c e -p o l i c ifie d w ith th e h e lp o f a p inte rf a ce c o m m a t su p p y h a s th e s h n d s to o rte d o n th e ta k e n e ffe c t ow c h e c k th e P P P a u t h e n t i c a t i o n i s n o t s t r i c t l y r e q u i r e d s i n c e a P V C i s l i k e a l e a s e d -l i n e H o w e v e r , P P P a u t h e n t i c a t i o n i s h a n d y a s t h e s h ow p p p m ul til ink c o m m a n d i s t h e n u s e d t o d e t e r m i n e t h e n a m e o f th e ro u te r a t th e o th e r e n d o f th e P V C F m e R e la y tra ffic s h a p in g m u s t b e e n a b le d fo r M L P o F R P V C s o n th e F m e R e la y ro u te r C i s c o I O S S o f t w a r e R e l e a s e 12 i n i t i a l l y s u p p o r t e d a m a x i m u m p e r ro u te r T h is lim ita tio n c a n im p a c t th e s c a le o f a n A T M d is trib re q u ire d to h a v e a u n iq u e IP a d d re s s T h e w o rk a ro u n d fo r a ffe c te u n n u m b e re d o r to u s e d ia le r in te rfa c e s in s te a d o f v irtu a l te m p la te 12 2(8) T , t h e s u p p o r t i s i n c r e a s e d t o 200 v i r t u a l t e m p l a t e s o f t w e n t y -f i v e u tio n ro u te r if d v e rs io n s is to s In C is c o IO S v irtu a l te m p la te s e v e ry P V C is u se IP S o ftw a re R e le a s e S o m e s e r v ic e p r o v id e r s d o n o t y e t s u p p o r t P P P tr a n s la tio n o n th e ir F R F 8d e v ic e s W h e n e v e r th is h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e 13 o f 21 lim ita tio n is in p la c e , th e p ro v id e rs m u s t c o n fig u re th e ir P V C s fo r tra n s p a re n t m o d e


M o s o r A a tta c T h is t e x a m T M su h e d to is e s p p le s in b -i n t e r th e p h e c ia lly th e fa c e y s ic im p C is c o T h is a l in te o rta n t IO su rfa if S d o c u m e n ta tio n b -i n t e r f a c e s e r v e s c e T h e re s u lt is a th e re a re a la rg e n sh o n o m o u m w p u re b e c o n fig u rp o se T c o m p a c r o f P V C tio n s th a t in c lu d e a F m e R e la y h e v irtu a l te m p la te s h o u ld ju s t b e t a n d m a n a g e a b le c o n fig u tio n s U s e t h e s h ow p p p m ul til ink c o m m a n d a s a f o o l -p r o o f w a y t o d e t e r m i n e i f t h e r e a r e a n y c e ll/fra m e d ro p s o n th e c a rrie r s id e T h e o n ly a c c e p ta b le fra g m e n t lo s s is o n e c a u s e d b y c y c lic r e d u n d a n c y c h e c k (C R C ) e r r o r s A lth o u g h M L P o A T M /F m e R e la y w a s in in th is a n d s u b s e q u e n t re le a s e s d ic ta te th a t R e le a s e C is c o re c o m m e n d s to u s e th e la te m a in s tre a m H o w e v e r, o th e r V o IP fe a tu re I O S S o f t w a r e R e l e a s e , s u c h a s 12 2(2) X T re q u ire d T h is ta b le lis ts s o m e o f th e k n o w ID s h o u ld b e e v a lu a te d a g a in s t th e c h o s e n C is co b ug ID C S C d t 09293 (re g is te re d c u s to m e r s o n ly ) C S C d t 25586 (re g is te re d c u s to m e r s o n ly ) C S C d t 29661 (re g is te re d c u s to m e r s o n ly ) C S C d t 53065 (re g is te re d c u s to m e r s o n ly ) tro d u c e d in c a re b e ta k s t m a in te n a re q u ire m e n if S u rv iv a b n is s u e s W IO S is c o IO S S o ftw a r w h e n y o u s e le c t e re le a s e o f th e C c a n d ic ta te th e u s R e m o te S ite T e le n y o u s e le c t C is c e R e l e a s e 12 1(5) T , th e C is c o IO S S o ftw i s c o I O S 12 e o f a d iffe re n t C is c p h o n y (S R S T ) i s o IO S , e a c h C is c o b b u g s a re o u g D e s crip tion L F I - F a s t s w i t c h i n g o n 7200 c a u s e s o n e w a y v o ic e c a lls P P P o A a c c e s s fla p p in g o r s w itc h e d v i r t u a l c i r c u i t (S V C ) n o t t o r n d o w n o n id le tim e o u t M L P -S h u td o w n o f A T M in te rfa c e d u rin g fa s t s w itc h in g c s h e s ro u te r P e rfo rm a n c e im p ro v e m e n t in a tm _ lfi c o d e fo r A T M L F I fe a tu re C S C d t 59038 (re g is te re d c u s to m e r s o n ly ) M L P o A T M : P in g w ith la rg e p a c k e ts f a i l o n P A -A C S C d u 19297 (re g is te re d c u s to m e r s o n ly ) M L P o A T M P V C w ith o u t s e rv ic e p o lic y g e n e te s e rro rs C S C d u 18344 (re g is te re d c u s to m e r s o n ly ) C e n n c ts le h e M L P o A T M /F m e R e la y P V C th ro u g h p u t is le s s th a n h a lf o f S C R /C IR C S C d u 41056 (re g is te re d c u s to m e r s o n ly ) M L P o A T M : D riv e r v c _ s o u u t ro u tin e g e ttin g c a lle d tw ic e C S C d u 44491 V irtu a lA c c e s s c o u n te rs in c o rre c t in h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M (re g is te re d c u s to m e r s o n ly ) C S C d u 51306 (re g is te re d c u s to m e r s o n ly ) C S C d u 57004 (re g is te re d c u s to m e r s o n ly ) C S C d u 84437 (re g is te re d c u s to m e r s o n ly ) C S C d v 03443 (re g is te re d c u s to m e r s o n ly ) C S C d v 10629 (re g is te re d c u s to m e r s o n ly ) C S C d v 20977 (re g is te re d c u s to m e r s o n ly ) C S C d w 44216 (re g is te re d c u s to m e r s o n ly ) C S C d y 70337 (re g is te re d c u s to m e r s o n ly ) C S C d x 71203 (re g is te re d c u s to m e r s o n ly ) P a g e 14 o f 21 M L P o F R K e e p a liv e s b ro k e n o n P P P o X C E F d o e s n o t w o rk w ith M L P F lo w c o n tro l im p le m e n ta tio n b e tw e e n M L P a n d t x -r i n g t u n e d d r i v e r s C o m m i t f i x f o r u 76585 o n C i s c o I O S ® S o f t w a r e R e l e a s e 12 - I n c o m i n g M L P p a c k e ts a re p ro c e s s s w itc h e d M L P o A T M : V o ic e p a c k e ts a re n o t q u e u e d a t L L Q In c o m in g M L P p a c k e ts a re g e ttin g p ro c e s s s w itc h e d c R T P c a u s e s h ig h C P U w h e n C B W F Q /L L Q lin k re a c h e s c o n g e s tio n W h e n a n M L P b u n d le s w ith Q o S s e rv ic e p o lic y is in u s e A n M L P b u n d le m ig h t o c c a s io n a lly h a v e a fe w in a c tiv e lin k s Ca se S tu d y I ntro d uc tio n T h is s e c tio n T h e c u s to m e a n IP T e le p h in te rw o rk in g s w itc h e s to d d e s c rib e s o n r is re fe rre d o n y s o lu tio n w a s c h o se n e liv e r th e A e o to A fo T M f th e firs t c u s to m e r d e p b y th e fic titio u s n a m e X s p a rt o f th is p ro je c t, a r th e W A N T h e c a rrie r a n d F m e R e la y s e rv lo y m Y Z n e w th a t ic e s e n ts o f th e M L L t d I n 2001, X IP n e tw o rk w a p ro v id e s th e W P o A Y Z s b u A N T M /F L td re ilt a n d s e rv ic m p la c F e u s e R e la y fe a e d th e ir P B m e R e la y /A e s N e w b rid tu re X s w ith T M g e N etw o rk O v erv iew T h e X Y Z L t d n e t w o r k i s a h u b a n d s p o k e n e t w o r k t h a t c o n n e c t s t w e n t y -s i x b r a n c h e s w i t h t w o c o r e s i t e s E a c h o f t h e c o r e s i t e s i s s e r v e d b y a n E A T M a t t a c h e d C i s c o 3660 r o u t e r E i g h t e e n o f t h e t w e n t y - h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M s ix tw o c o n a re fig u b n c h e s a re c o re s ite s th n e c t b a c k to C i s c o 2620 re illu s tra te s m e d iu m s iz ro u g h A T M th e c lo s e s t m A n e n d -t o -e th e to p o lo g e d T h e y h /F m e R e e d iu m s iz n d A T M P y a v e d la y IW e d b r V C c u a l F m T h e r a n c h th r o n n e c ts e R e la y P V C s th a e m a in in g e ig h t b o u g h a s in g le F m t h e t w o 3660 r o u t e t c n c e rs o n n e c h e s a r R e la y a t th e P a g e 15 o f 21 t b e v P V tw a c e r C o k t o t h e 3660s a t t h e y s m a ll T h e y A ll b n c h ro u te rs h u b s ite s T h is T h i s t a b l e s h o w s t h e F r a m e R e l a y a c c e s s s p e e d s a n d C I R T h e C I R v a r i e s f r o m 32 k b p s t o 256 k b p s A ls o s h o w n in th e ta b le is th e m a x im u m n u m b e r o f s im u lta n e o u s V o IP c a lls c a rrie d b y e a c h P V C S ite B n c h R e m ote S ite N um b e r of C a lls B r a n c h 22 128 64 C o re 256 B r a n c h 16 64 32 C o re 128 64 B n c h B n c h 64 32 B n c h C o re 512 256 B n c h B n c h B n c h 320 C IR (k b p s) 192 B n c h C o re A cce s s (k b p s) 576 h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e 16 o f 21 B n c h 512 256 B r a n c h 13 128 256 C o re 256 128 C o re 128 96 C o re 128 64 C o re 768 256 12 C o re 192 96 C o re 192 96 C o re 448 192 B r a n c h 13 128 64 C o re 128 96 B r a n c h 16 128 64 B n c h 20 C o re 64 32 B n c h 21 C o re 34000 256 12 B r a n c h 13 128 64 C o re 384 192 C o re 512 256 C o re 192 96 C o re 128 96 B n c h 64 32 B n c h B n c h 10 B n c h 11 B n c h 12 B n c h 13 B n c h 14 B n c h 15 B n c h 16 B n c h 17 B n c h 18 B n c h 19 C o re B n c h 22 B n c h 23 B n c h 24 B n c h 25 B n c h 26 C o re h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M F m e R e la y tra ffic s h a p in g is p e rfo rm e C is c o IO S tra ffic s h a p in g is s e t to s h a p e e x p l i c i t c o n g e s t i o n n o t i f i c a t i o n s (B E C N m in c ir T h is a p p ro a c h is a g a in s t C is c o r a lre a d y in tro u b le b y th e tim e th e ro u te r c a rrie r b e lie v e s th a t its n e tw o rk is s u ffic h e n c e , B E C N s s h o u ld n e v e r b e s e e n A T M tra ffic s h in s ta n c e , if th e u s e d to m a x im th e c a rrie r s id e a p a c iz e is in g is s e t to c e ss sp e e d th ro u g h p u c o n fig u re d sh a p e a i s 512 K t T h is is g e n e ro u c R T P is u s e d a ro u te r a t c o re s m a x im u m n u m g p h in d ic a te a p p ro x im a te ly c ro s s th e W A N T h e h o t i t e B y a d d i n g t h e n u m b e r o f V o IP c a lls th a t tra t h a t t h e C i s c o 3660 C P U 50 p e r c e n t P a g e 17 o f 21 d b y th e b n c h ro u te rs B u rs tin g b e y o n d C to th e a c c e s s s p e e d , w ith m in c ir e q u a l to C s ) a re re c e iv e d fro m th e c a rrie r, th e n th e ro e c o m m e n d a tio n s w h e n d o in g V o IP o v e r F r re s p o n d e d to c o n g e s tio n n o tific a tio n s H o w ie n tly o v e r p ro v is io n e d to n e v e r d ro p a n y f t th e b p s, sa fe s ly s sp b e v e lo fra m th e n b e c a o th a e a c c e ss S C R is s u s e c e ll t th e s lig o t a s fa r a s C rs in th e a b o v rs e th is ro u te a d f o r 100 c R IR is p e rm itte d IR If b a c k w a rd u te r th ro ttle s b a c k to a m e R e la y V o ic e is e v e r, in th is c a s e th e m e s o r c e lls , a n d s p e e d a t th e re m o te e n d , p e t t o 512x 53/ 48 = 565 K b ta x is s trip p e d a t th e IW p h t o v e rs u b s c rip tio n is a llo lu s c e ll ta x F o r p s T h is s h a p in g te is o in t T h e p o lic in g o n w e d P U e ta r is T P c o a t n st is c o n c e rn e b le , it is d e 102 c a l l s P s e s s i o n s (w d is te rm e rfo h ic th e C in e d rm a n h a re is th c e fa 3660 d i s t r i b u t i o n th e th e o re tic a l u m b e rs fro m th is s w itc h e d ) is V irtu a l te m p la te s a re u s e d w ith IP n u m b e re d W A N lin k s O n e v irtu a l te m p la te is re q u ire d p e r P V C w h i c h i s p o s s i b l e s i n c e t h e t o t a l n u m b e r o f P V C s t h a t t e r m i n a t e o n e a c h C i s c o 3660 i s l e s s t h a n t w e n t y fiv e C o nf ig ura tio ns T h is d o c u m e n t u s e s th e s e c o n fig u tio n s :
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B n c h F m e R e la y R o u te r C ore A T M !- - !- - - Note: T h i s s e c t i o n c o n f i g u r a t i o n t h a t R oute r s h o w s t h e p a r t s o f a c o r e i s r e l e v a n t t o M L P o A T M C i s c o 6 r o u t e r h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M c lass-map matc h ac c lass-map matc h ac matc h-all V o c ess-gro u p matc h-all V o c ess-gro u p P a g e 18 o f 21 ic e_ S tream 0 ic e_ C o ntro l p o lic y-map to o rtr0 c lass V o ic e_ S tream p rio rity c lass V o ic e_ C o ntro l bandwidth rando m-detec t interfac e lo o p bac k ip address 5 5 5 interfac e A T M /0 desc rip tio n T o C arrier E no ip address A T M S erv ic e interfac e A T M /0 p o int-to -p o int p v c to o rtr0 /5 v br-nrt 6 tx-ring-limit p ro to c o l p p p V irtu al-T emp late1 interfac e V irtu al-T emp late1 bandwidth ip u nnu mbered lo o p bac k ip tc p header-c o mp ressio n ip hc -fo rmat serv ic e-p o lic y o u u t to o rtr0 p p p mu ltilink p p p mu ltilink fragment-delay p p p mu ltilink interleav e ip rtp header-c o mp ressio n ip hc -fo rmat !!!!!!!!!!- - - - - - - - - - - - D o r e s s s a t h a i n t a s e t e s I P a P a d n s t a Note: I P a d d s u c h a e x i s t s a c t i v e r a r e c I P r o u I f a n t h i s I I P i n o t e s d v i r t t t h e r f a w h e r a n d d d r e d r e s l l s c o n i r e u a l i s c e s f i g c t l t e i n f e t h s i a h a v e s s i r o y u r e o n m p l o r m T h e e i n t I P d s p r e s c o p u t e t a n y a t e , a t i o n e x c e p e n t i o l o a s e n t i e d t o e a c c o n w h e n i s t i o n s t o d b a o n t o a l h o f f i g e v e c l t o d e l a n h e u r a t r t h o n e d t h i f i n e c i n g c o n f l t h e c t h e s e i o n e t s m b i g l o i n s o p o s s o m u r u l e u l t i e t w e u r a t n e d t e r f u r c i b i l t i i s p l e e n i o n i n t a c e e , l i t p l e t h p a t h e s o e r f s y e r a l l e l m u r c e , a c e s B nch F m e R e l a y R oute r !- - !- - - Note: T h i s s e c t i o n s h o w s t h e p a r t s c o n f i g u r a t i o n s t h a t i s r e l e v a n t t o c lass-map o f a b r a n c h M L P o F R C i s c o 0 r o u t e r matc h-all V o ic e_ S tream h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e 19 o f 21 matc h ac c ess-gro u p 0 c lass-map matc h-all V o ic e_ C o ntro l matc h ac c ess-gro u p 1 p o lic y-map dhartr2 c lass V o ic e_ S tream p rio rity c lass V o ic e_ C o ntro l bandwidth rando m-detec t interfac e lo o p bac k ip address 5 5 5 interfac e S erial0 /0 desc rip tio n T o C arrier F rame R elay S erv ic e enc ap su latio n frame-relay I E T F frame-relay traffic -shap ing interfac e S erial0 /0 p o int-to -p o int frame-relay interfac e-dlc i p p p V irtu al-T emp late1 c lass dhartr2 interfac e V irtu al-T emp late1 bandwidth ip u nnu mbered lo o p bac k max-reserv ed-bandwidth 85 serv ic e-p o lic y o u u t dhartr2 p p p mu ltilink p p p mu ltilink fragment-delay p p p mu ltilink interleav e map -c lass frame-relay dhartr2 frame-relay adap tiv e-shap ing bec n frame-relay c ir 0 0 frame-relay bc 0 frame-relay minc ir 0 0 N etP r o D i sc u ssi on F or u m s - F ea tu r ed Conv er sa ti ons N e tw o rk in g P ro fe s s io n a ls C o n n e c tio n is a fo ru m fo r n e tw o rk in g p ro fe s s io n a ls to s h a re q u e s tio n s , s u g g e s tio n s , a n d in fo rm a tio n a b o u t n e tw o rk in g s o lu tio n s , p ro d u c ts , a n d te c h n o lo g ie s T h e fe a tu re d lin k s a re s o m e o f th e m o s t re c e n t c o n v e rs a tio n s a v a ila b le in th is te c h n o lo g y N e tP ro D is c u s s io n F o ru m s -F e a tu re d C o n v e rs a tio n s fo r V o ic e S e rv ic e P ro v id e rs : V o ic e o v e r IP W h e r e c a n I l e a r n t h e s t r u c t u r e o f V o i c e g a t e w a y ? - O c t 12, 2007 M u l t i p l e S L T s u p p o r t o n A S 5400 - O c t 12, 2007 P r o b l e m s w i t h B A R S 12 - O c t 11, 2007 G a t e w a y n o t r e g s t e r i n g t o C C M - O c t 11, 2007 3725 F X O I s s u e s - O c t 10, 2007 V o ic e & V id e o : V o ic e o v e r IP C a l l f o r w a r d a l l e x c e p t i o n - O c t 12, 2007 C i s c o C C M a n d T a n d b e r g V C G a t e k e e p e r a n d G a t e w a y - O c t 11, 2007 h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M P a g e 20 o f 21 T a n d b e r g M X P 6000 w i t h C C M - O c t 11, 2007 S i m p l e V T A d v a n t a g e Q u e s t i o n - O c t 11, 2007 A t t e n d a n t C o n s o l e - O c t 10, 2007 V o ic e & V id e o : IP T e le p h o n y E x t e n s i o n M o b i l i t y - O c t 12, 2007 H o w T o c o n f i g V G 224 w i t h M G C P A N D S C C P - O c t 12, 2007 C C M o n V M W A R E - O c t 12, 2007 T I M E Z O N E S i n C A L L M A N A G E R - O c t 12, 2007 C a l l M a n a g e r D i s a s t e r R e c o v e r y B a c k u p (B U G ) - O c t 12, 2007 V o ic e & V id e o : IP P h o n e S e rv ic e s fo r E n d U s e rs E x t e n s i o n M o b i l i t y - O c t 12, 2007 D e l e t e I P P h o n e s e r v i c e s - O c t 11, 2007 D I D n u m b e r n o t w o r k i n g - O c t 11, 2007 U p g r a d e f r o m t o - O c t 11, 2007 I P p h o n e d i s p l a y n a m e o f t h e c a l l e d p a r t y w i t h g r a b a g e - O c t 11, 2007 V o ic e & V id e o : U n ifie d C o m m u n ic a tio n s U n i t y M e s s a g e I n d i c a t o r - O c t 12, 2007 H e l p w i t h A A i n U n i t y - O c t 12, 2007 I s U n i t y c o m p a t i b l e w i t h M i c r o s o f t E x c h a n g e 2007? - O c t 12, 2007 C a l l h a n d l e r w i t h t i m e s c h e d u l e s - O c t 12, 2007 I P P h o n e F i r m w a r e U p d a t e - A l t e r n a t i v e M e t h o d - O c t 11, 2007 V o ic e & V id e o : IP P h o n e S e rv ic e s fo r D e v e lo p e rs 7970 h a n g s o n r e q u e s t s - O c t 11, 2007 I P A d d r e s s P r o v i d e r T h e a p p n e v e r e n d s (J a v a ) C C M - O c t 11, 2007 C a l l M a n a g e r - r e p o r t i n g o n h u n t g r o u p i n f o r m a t i o n - O c t 11, 2007 C a l l M a n a g e r E x p r e s s & C i s c o I P P h o n e E x e c u t e (O n e f o r t h e E x p e r t s ) - O c t 10, 2007 N o a u t h e n t i c a t i o n f o r h t t p p o s t i n t c l / i v r - O c t 10, 2007 V o ic e & V id e o : G e n e l T 37 o n r a m p - O c t 12, 2007 P r o b l e m w i t h U p g r a d i n g C M - O c t 11, 2007 C U E S c r i p t - A l l o w i n g m o r e t h a n o n e d i g i t i n p u t - O c t 11, 2007 A u t o m a t i c D i a l e r t o B r o a d c a s t V o i c e M e s s a g e - O c t 11, 2007 F X S p o r t c o n n e c t e d b u t t h e c a l l i n g p h o n e k e e p s r i n g i n g - O c t 11, 2007 R el a ted I nf or m a ti on






V oIP ov e r F m e R R T P P riority ) V oIP Q oS f or F m C onf ig uring L ink F C ircuits P P P O v e r A A L 5, R P P P in F m e R e l a T h e P P P M ul til ink C om p re s s ing IP / U D e l a y w ith Q ua l ity of S e rv ice ( F g m e nta tion, T f f ic S h a p ing , L L Q / IP e R e l a y to A T M Inte rw ork ing w ith L L Q , P P P L F I a nd cR T P g m e nta tion a nd Inte rl e a v ing f or F m e R e l a y a nd A T M V irtua l F C , J ul y 9 y , R F C , J une 9 P rotocol ( M P ) , R F C 7 , N ov 9 P / R T P H e a de rs f or L ow -S p e e d S e ria l L ink s , R F C 50 , F e b 9 h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 C is c o -D e s ig n in g a n d D e p lo y in g M u ltilin k P P P o v e r F r a m e R e la y a n d A T M





P a g e 21 o f 21 F m e R e l a y / A T M P V C S e rv ice Inte rw ork ing Im p l e m e nta tion A g re e m e nt F R F F m e R e l a y F g m e nta tion Im p l e m e nta tion A g re e m e nt F R F V oice T e ch nol og y S up p ort V oice a nd IP C om m unica tions P roduct S up p ort R e com m e nde d R e a ding : T roub l e s h ooting C is co IP T e l e p h ony T e ch nica l S up p ort & D ocum e nta tion - C is co S y s te m s A ll c o n te n ts a re C o p y rig h t © 0 -2 0 C i s c o S y s t e m s , I n c A l l r i g h t s r e s e r v e d I m p o r t a n t N o t i c e s a n d P r i v a c y S t a t e m e n t h t t p : / / k b a s e / p a w s / s e r v l e t / V i e w F i l e / 25084/ d e s i g n i n g -m l p -o v e r -f r -a t m x m l ? c o n v e r t P a t h s = 10/ 12/ 2007 ... interleav e map -c lass frame- relay dhartr2 frame- relay adap tiv e-shap ing bec n frame- relay c ir 0 0 frame- relay bc 0 frame- relay minc ir 0 0 N etP r o D i sc u ssi on F or u m s - F ea tu r ed Conv... max-reserv ed-bandwidth 85 serv ic e-p o lic y o u u t dhartr2 p p p mu ltilink p p p mu ltilink fragment-delay p p p mu ltilink interleav e map -c lass frame- relay dhartr2 frame- relay adap tiv... l bandwidth rando m-detec t interfac e lo o p bac k ip address 5 5 5 interfac e S erial0 /0 desc rip tio n T o C arrier F rame R elay S erv ic e enc ap su latio n frame- relay I E T F frame- relay