# Trouble with an open QueueingNetworkProcess: Missing Performance measures

I'm trying to create the following open network using Mathematica: First of all, I define the variables of this network, in this way:

g = {2, 2, 0, 0, 2};
p = {{0, 1/4, 0, 0, 3/4}, {0, 0, 1/3, 2/3, 0}, {0, 0, 0, 0, 0}, {0, 0,
0, 0, 0}, {0, 1/2, 0, 1/2, 0}};
m = {3, 3, 3, 3, 3};
c = {1, 1, 1, 1, 1};


Then, I execute the function QueueingNetworkProcess with those values:

NET = QueueingNetworkProcess[g, p, m, c];


I don't know why, but when I execute the QueueProperties function, sometimes Performance Measures outputs "Missing[NotAvailable]".

Table[QueueProperties[{NET, i}], {i, 1, 5}] I want to get values for the Mean Time for a traffic going by 1-5-2-4. Theoretically I have to get the following, supposedly: I think I'm doing well, but there's the problem of that Missing thing. Anyone knows how to solve this?

If your queues' lengths diverge you'll get that kind of answer. Consider the simpler:

γ = {3, 3}; μ = {1, 1};
r = {{0, 1/2}, {1/4, 0}};
c = {1, 1};
net = QueueingNetworkProcess[γ, r, μ, c];
Table[QueueProperties[{net, i}], {i, 1, 2}] versus the same, but increasing the service rate:

μ = {10, 10};
net = QueueingNetworkProcess[γ, r, μ, c];
Table[QueueProperties[{net, i}], {i, 1, 2}] Your problem works if you set the service vector values greater than 4.

• To be precise, the following vector will do: m = {3, 17/4 + ϵ, 3, 55/12 + ϵ, 7/2 + ϵ}; for any ϵ>0 – Sjoerd C. de Vries Jan 5 '16 at 21:00
• Thanks to both of you, it worked. I was getting obfuscated with that kind of error :) – Alvurion Jan 5 '16 at 21:06