Task $2$ Network Operating Systems $20$ marks $600$ words

a$)$ Explain the term $$Network Operating System$($NOS$).$ In your answer, you must

discuss the advantages or disadvantages of using a proprietary NOS or an opensource NOS. You should provide at least THREE $(3)$ advantages or disadvantages.

You must also provide TWO $(2)$ named examples of Network Operating Systems.

$(10$ marks$)$

b$)$ Explain what issues an enterprise network could face if they do not update their

NOS once it reaches End of Life $($EoL$).$ You should provide a minimum of FIVE $(5)$

issues.give me refeferences also please