Accounts Receivable

6 Months Ended

Apr. 30, 2012

Receivables [Abstract]

ACCOUNTS RECEIVABLE

ACCOUNTS RECEIVABLE

As of April 30, 2012, one customer accounted for greater than 10% of accounts receivable and represented 11.3% of net accounts receivable.

Allowance for doubtful accounts was $0.7 million and $1.7 million as of October 31, 2011 and April 30, 2012, respectively. Ciena has not historically experienced a significant amount of bad debt expense.