No. Monsters used as Link Material are not Tributed.

Is Link summoning special summoning?

Synchro Summons, Xyz Summons, Pendulum Summons, Link Summons and Contact Fusions are all considered Special Summons By Condition. In addition, all Nomi and Semi-Nomi monsters (collectively known in Japanese as "Special Summon monster") are summoned wih their Summoning conditions.

Is Tributing normal summoning?

A Tribute Summon is treated exactly as Normal Summon, except a few cards refer specifically to whether or not the card was Tribute Summoned (such as Monarchs). Normally only one Tribute Summon can be conducted in the same turn (exceptions: see "Ultimate Offering" and "Double Summon").