Is openfire the right software  to scale beyond a couple of thousand concurrent connections?

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    Is openfire the right software  to scale beyond a couple of thousand concurrent connections?

    If I refer myself to this post Comparison between Tigase, Openfire and any other open-source XMPP servers - Stack Overflow

    it says I should avoide openfire for hish scale websites, is this true?

    This post says that tigase is capable of scaling high compare to openfire,

    can someone duide me,

    regards, Heather