Accounts Receivable

6 Months Ended

Apr. 30, 2013

Receivables [Abstract]

ACCOUNTS RECEIVABLE

ACCOUNTS RECEIVABLE

As of October 31, 2012, no single customer accounted for greater than 10% of net accounts receivable. As of April 30, 2013, two customers each accounted for greater than 10% of net accounts receivable, and in aggregate accounted for 28% of net accounts receivable. Allowance for doubtful accounts was $1.5 million and $1.6 million as of October 31, 2012 and April 30, 2013, respectively. Ciena has not historically experienced a significant amount of bad debt expense.