Telecoms companies have different departments that work together. Each department is responsible for a certain aspect of the network. Eg One department does the installations, another does maintenance, another plans and optimisises the network. They usually provide training for a job, and I'm not sure if a masters would help out much.
You could also look into working with vendors, for example ericsson, nokia siemens, motorolla, huawei, alcatel etc. They supply the operators with the equipment and support for the equipment, which would maybe allow you to work in all aspects of network, and maybe that is where a masters or mtech would be more suitable. Not sure tho.
I know ericsson has a student/ learnership program, I went to a presentation last year, best to look at the websites of the various companies to get an idea for where you want to work and what the requirements for the job you want are.