Accounts Receivable (Tables)

12 Months Ended

Oct. 31, 2020

Receivables [Abstract]

Activity in allowance for doubtful accounts

The following table summarizes the activity in Ciena’s allowance for doubtful accounts for the fiscal years indicated (in thousands):

Year Ended	Beginning Balance		Provisions		Net Deductions		Ending Balance
November 3, 2018	$	17,580	$	2,700	$	2,902	$	17,378
November 2, 2019	$	17,378	$	6,740	$	4,017	$	20,101
October 31, 2020	$	20,101	$	8,855	$	18,358	$	10,598