Router-router jinis kasebut padatanipun gadhah fungsi firewall kangge napis paket adhedhasar alamat sumber lan alamat tujuan paket kasebut. Ananging wonten ugi router ingkang boten gadhah punika. Router ingkang gadhah fitur napis paket dipunwastani packet-filtering router. Padatanipun router mblokir lajeng lintas data ingkang kapancar kanthi cara broadcast saéngga saged nyegah broadcast strom ingkang saged ngganggu kinerjaning jaringan.