伝送 でんそう制御 せいぎょ拡張 かくちょうでしょう
densōseigyokakuchōdeshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 伝送制御拡張

1. Probably transmission control extension.

Polite
Presumptive
Conjecture