Creating new Enterprise wiki site collection or creating a new subsite, or creating a new library

Question

I have SharePoint 2013 web application, which has enterprise wiki site collection for our finance department. Now I need to create a new site for our HR department.
The two sites will differ in the following:-
Each department have different permission. For example each department have different users for who can approve, edit/create.
Each department will use different EnterpriseWiki page layout. As each department will have different wiki category columns (different site columns).
Also each department will use different metadata navigation.
The two sites will have the following in common:-
The same master page. Seatle.html.
So I can not determine which approach I should follow:-
To create a new enterprise wiki site collection for our HR department.
Create a new enterprise wiki library inside the current site collection representing the HR enterprise wiki.
To create a new subsite ?
Can anyone advice on these please? Thanks

Answer 1

Given that each will have different permissions I would go with a separate site collection.  That will provide the best security basis.  You could do it with a sub site, but it will be easier to maintain the security as a separate site
collection.
Paul Stork SharePoint Server MVP
Principal Architect: Blue Chip Consulting Group
Blog: http://dontpapanic.com/blog
Twitter: Follow @pstork
Please remember to mark your question as "answered" if this solves your problem.
Yes i know that having different permission & different page layouts will push toward creating separate site collections. but i found a major linking problem when using different site collections (i mean adding links which reference other site collections
pages), let take the following example:-
1. I have Site collection A & site collection B.
2. now inside SCA i create a new wiki page named "Test.aspx" page.
3. then inside SCA i add a link to this wiki page from another wiki page.
4. also inside SCB i also add a link to the Test.aspx page.
After that let say i modify the Test.asxp page name & title to be "NewTest.aspx" , which will affect the page URL which will be
http:.../NewTest.aspx/ instead of
http.../Test.aspx/. now inside SCA all the links to the old Test.aspx page will automatically updated to reference the NewTest.aspx so that the links will not break. but inside SCB pages, the links will not be modified and will keep referencing Test.asxp
which no more exists ... so can you advice please if there is a way to overcome this problem , and if i create sub-site representing Site collection B will this solve the problem ?