Connection admission control system

A connection admission control system, which comprises ATM switching means for securing a network line band on the basis of a call connection request from a B-ISDN terminal means for transmitting the call connection request to the ATM switching means, comprising:

• call acceptance control means for executing a switching routine and a band allocation in response to a statement of traffic parameters transmitted from said B-ISDN terminal means;
• fuzzy control means accessed by said call acceptance control means, for estimating a call band of the call connection request in accordance with fuzzy rules;
• cell traffic measuring means for observing a status of cell traffic transmitted from said B-ISDN terminal means;
• and
• a traffic information database for storing information related to a transmission line band;
• and
• said cell traffic measuring means observing the status of cell traffic incoming from the B-ISDN terminal means, and further calculating an estimated band value on the basis of the traffic parameters obtained from the incoming cell traffic status and in accordance with the fuzzy rules of said fuzzy control means, and further updating a traffic information database on the basis of the estimated band value.

A call acceptance method having fuzzy control means for analyzing traffic parameters, for calculating a necessary band in accordance with fuzzy rules, and for discriminating whether a call set up for the call is acceptable, comprising the following steps of:

• inputting traffic parameters stated from each B-ISDN terminal and parameters xk (1.ltoreq.k.ltoreq.m, m:
• natural numbers) decided by the traffic parameters indicative of network traffic status at a call request from the B-ISDN terminal;
• calculating respective band estimation values yi (1.ltoreq.i.ltoreq.n) on the basis of n-piece fuzzy rules R1, . . . Rn composed of antecedents of fuzzy variables represented by predetermined membership functions Mj,k (0.ltoreq.j.ltoreq.n, 0.ltoreq.k.ltoreq.m, m, n:
• natural numbers) and consequents in which the band estimation values yi (1.ltoreq.i.ltoreq.n) of outputs are represented by functions fi (xk) (1.ltoreq.i.ltoreq.n) of the input xk (1.ltoreq.k.ltoreq.m) as:
• [Formula 1]
• R1=if x1 is M11 and x2 is M12 and . . . xm is M.sub.1m then
• y1=f1 (x1, x2, . . . xm)
• R2=if x1 is M21 and x2 is M22 and . . . xm is M.sub.2m then
• y2=f2 (x1, x2, . . . xm)
• Ri=if x1 is Mi1 and x2 is Mi2 and . . . xm is M.sub.1m then
• yi=fi (x1, x2, . . . xm)
• Rn=if x1 is Mn1 and x2 is Mn2 and . . . xm is M.sub.2m then
• yn=fn (x1, x2, . . . xm)
• calculating adaptabilities .omega.i (1.ltoreq.i.ltoreq.n) in accordance with a formula as ##EQU13## where Mik (xi) denotes grades of fuzzy variables Mik at xi;
• estimating an estimated value y corresponding to the B-ISDN terminal (1) by calculation on the basis of the band estimation values yi (1.ltoreq.i.ltoreq.n) and the adaptabilities .omega.i (1.ltoreq.i.ltoreq.n) of the respective fuzzy rules R1, . . . Rn and in accordance with a formula as ##EQU14## and discriminating acceptance or rejection of the call from the B-ISDN terminal on the basis of the estimated band allocation value.