0000950133-01-501246 Sample Contracts

Exhibit 4.8 CYRAS SYSTEMS, INC. 4 1/2% Convertible Subordinated Notes Due August 15, 2005 FIRST SUPPLEMENTAL INDENTURE Dated as of November 27, 2000

First Supplemental Indenture • May 17th, 2001 • Ciena Corp • Telephone & telegraph apparatus • New York

• Contract Type
  First Supplemental Indenture
• Filed
  May 17th, 2001
• Company
  Ciena Corp
• Industry
  Telephone & telegraph apparatus
• Jurisdiction
  New York

Exhibit 4.9 CYRAS SYSTEMS, INC. 4 1/2% Convertible Subordinated Notes Due August 15, 2005 SECOND SUPPLEMENTAL INDENTURE Dated as of November 28, 2000

Second Supplemental Indenture • May 17th, 2001 • Ciena Corp • Telephone & telegraph apparatus • New York

• Contract Type
  Second Supplemental Indenture
• Filed
  May 17th, 2001
• Company
  Ciena Corp
• Industry
  Telephone & telegraph apparatus
• Jurisdiction
  New York

to INDENTURE Dated as of August 18, 2000

Third Supplemental Indenture • May 17th, 2001 • Ciena Corp • Telephone & telegraph apparatus • New York

• Contract Type
  Third Supplemental Indenture
• Filed
  May 17th, 2001
• Company
  Ciena Corp
• Industry
  Telephone & telegraph apparatus
• Jurisdiction
  New York