0000891618-99-001738 424B3 1 19990423 CISCO SYSTEMS INC 0000858877 3576 770059951 CA 0731 424B3 33 333-67789 99599700 170 WEST TASMAN DRIVE SAN JOSE CA 95134-1706 4085264000 225 WEST TASMAN DRIVE SAN JOSE CA 95134-1706 424B3 1 000089161899001738-001-seq1-424b3.txt PROSPECTUS SUPPLEMENT DATED APRIL 22, 1999