frame relay , .
, .25 TCP/IP RSVP, Internet. frame relay .
, .
CIR (Committed Information Rate) - , .
Be (Committed Burst Size) - , , .
Be (Excess Burst Size) - , , .
, : =Bc/CIR. CIR , .
CIR, Be, Be . 6.27.
. 6.27. : R - ; f1-f4
frame relay , .
, , . . Q.931/933 CIR, Be .
- , , . , CIR. , , DE(Discard Eligibility), 1, , . , , , . , DE=1 .
, , , +. , DE, .
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. 6.27 , 5 . R /, CIR. f1, f2 f3 , , DE=0. 4, f1, f2 f3, , +, f4 , DE=1. f5, , +, .
frame relay (Leaky Bucket). . ( 0, , ). , , DE=0. , , , +, , DE=1. , , , +, .
, .
, CIR . , . , , DE=1. , , .
, Be, CIR . DE=1, , Be . Be/R, R .
. 6.28 frame relay . CIR . , CIR, Bc Be. , 1 CIR, 128 /, 128 /, 1 1,544 / +.
. 6.28. frame relay
. , . 6.28 1 2 DLCI=136. 1 2 128 / =256 ( 1 ) =64 . 256 / =512 =128 .
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frame relay. , . , - . DE=1 , +.
frame relay () . , ( ). FECN (Forward Explicit Congestion Bit) . (TCP/IP, SPX . .) , .
BECN (Backward Explicit Congestion Bit) . BECN frame relay - , CSU/DSU. frame relay , FECN BECN, , RNR .25. (TCP, SPX, NCP . .) . - - , , - frame relay .
FECN BECN . frame relay (Frame Relay Access Device, FRAD) BECN.
Q.931. .
frame relay, , D SETUP, , :
DLCI;
( .164, .121 ISO 7498);
;
CIR ;
;
Be .
, , CALL PROCEEDING - . , , (, , , ), SETUP . . frame relay , . , SETUP . CALL PROCEEDING . , - CONNECT, . , . CONNECT CONNECT ACKNOWLEDGE.
CONNECT ACKNOWLEDGE, . .