• For closed networks, the following server types are supported: $M/M/m$–FCFS, $-/G/\backslash infty$, $-/G/1$–LCFS-PR, $-/G/1$–PS and load-dependent variants.
• For open networks, the following server types are supported: $M/M/m$–FCFS, $-/G/\backslash infty$ and $-/G/1$–PS. General load-dependent nodes are $not$ supported. Multiclass open networks do not support multiple server $M/M/m$ nodes, but only single server $M/M/1$–FCFS.
• For mixed networks, the following server types are supported: $M/M/1$–FCFS, $-/G/\backslash infty$ and $-/G/1$–PS. General load-dependent nodes are $not$ supported.

INPUTS

N

N(c)

Number of requests in the system for closed networks. For single-class networks, N must be a scalar. For multiclass networks, N(c) is the population size of closed class $c$.

lambda

lambda(c)

External arrival rate (scalar) for open networks. For single-class networks, lambda must be a scalar. For multiclass networks, lambda(c) is the class $c$ overall arrival rate.

QQ{i}

List of queues in the network. This must be a cell array with $N$ elements, such that QQ{i} is a struct produced by the qnmknode function.

Z

External delay ("think time") for closed networks. Default 0.

OUTPUTS

U(k)

If $k$ is a FCFS node, then U(k) is the utilization of service center $k$. If $k$ is an IS node, then U(k) is the $traffic\; intensity$ defined as X(k)*S(k).

R(k)

average response time of service center $k$.

Q(k)

average number of customers in service center $k$.

X(k)

throughput of service center $k$.

Note that for multiclass networks, the computed results are per-class utilization, response time, number of customers and throughput: U(c,k), R(c,k), Q(c,k), X(c,k).

String literals are case-insensitive, so "closed", "Closed" and "CLoSEd" are all equivalent.

 QQ = { qnmknode( "m/m/m-fcfs", [0.2 0.1 0.1; 0.2 0.1 0.1] ), ...
        qnmknode( "-/g/1-ps", [0.4; 0.6] ), ...
        qnmknode( "-/g/inf", [1; 2] ) };
 V = [ 1 0.6 0.4; ...
       1 0.3 0.7 ];
 N = [ 2 1 ];
 [U R Q X] = qnsolve( "closed", N, QQ, V );