read this article  and check the list of references at the end:

http://www.hindawi.com/journals/jam/2014/374962/

regards.

I advice you to go over principal books on  various times of  networks:

Starting with Newman's "Networks", Supply networks, computer networks, transportation networks, Networks in Reliability , etc. Everywhere you will find some material on optimization,  characteristic for the types of networks studied.

Good luck,

Ilya Gertsbakh 

I'm assuming you want to know about queuing techniques for digital networks. If so, another possibility, for the very latest thinking on topics such as this, is to visit the Internet Engineering Task Force (IETF) site. Specifically, the list of working groups active in the IETF now.

https://datatracker.ietf.org/wg/

There are several IETF working groups that discuss queuing techniques, aimed at providing some specific type of service. So rather than try each one that sounds promising, I used their own search function, and came up with this impressive list of documents, often very recent ones.

https://www.google.com/search?as_sitesearch=ietf.org&q=queuing&Search=Search

You can see the wide variety of techniques mentioned, depending on what characteristics the service has to offer.

In short, queue optimization depends on what you are trying to achieve.