OTHER BALANCE SHEET DETAILS

As of the dates indicated, other long-term assets are comprised of the following (in thousands):



	October 31, 2013		April 30, 2014
Maintenance spares inventory, net	$	61,305	$	56,090
Deferred debt issuance costs, net	15,677		13,302
Embedded redemption feature	2,740		—
Restricted cash	2,053		141
Other	4,605		4,560
	$	86,380	$	74,093

Deferred debt issuance costs are amortized using the straight-line method, which approximates the effect of the effective interest rate method, through the maturity of the related debt. Amortization of debt issuance costs related to our convertible notes payable and the Credit Facility (described in Note 14 below), which is included in interest expense, was $3.0 million and $2.4 million during the first six months of fiscal 2013 and fiscal 2014, respectively.

As of the dates indicated, accrued liabilities are comprised of the following (in thousands):



	October 31, 2013		April 30, 2014
Warranty	$	56,303	$	56,167
Compensation, payroll related tax and benefits	98,770		64,113
Vacation	32,118		34,503
Current restructuring liabilities	674		677
Interest payable	6,186		6,179
Other	77,605		92,797
	$	271,656	$	254,436

The following table summarizes the activity in Ciena’s accrued warranty for the fiscal periods indicated (in thousands):



						Balance at
Six months ended	Beginning					end of
April 30,	Balance		Provisions	Settlements		period
2013	$	55,132	11,060	(11,463	)	$	54,729
2014	$	56,303	12,424	(12,560	)	$	56,167

As of the dates indicated, deferred revenue is comprised of the following (in thousands):



	October 31, 2013			April 30, 2014
Products	$	36,671		$	64,326
Services	75,499			77,967
	112,170			142,293
Less current portion	(88,550		)	(118,473		)
Long-term deferred revenue	$	23,620		$	23,820