Balance Sheets and Statements of Operations Components

Inventory

Components of inventory as of June 30, 2016 and December 31, 2015 are shown below (in thousands):



	June 30, 2016		December 31, 2015
Raw materials	$	6,340	$	9,418
Finished goods	7,993		8,873
Total inventory	$	14,333	$	18,291

Property and Equipment, net

Components of property and equipment, net as of June 30, 2016 and December 31, 2015 are shown below (in thousands):



	June 30, 2016			December 31, 2015
Equipment	$	39,128		$	35,836
Software	3,801			3,548
Furniture and fixtures	857			864
Leasehold improvements	2,536			2,492
Construction in progress	9			83
Property and equipment, gross	46,331			42,823
Less: accumulated depreciation and amortization	(37,414		)	(33,920		)
Total property and equipment, net	$	8,917		$	8,903

Depreciation and amortization on our property and equipment for the three months ended June 30, 2016 and 2015 was $1.8 million and $2.2 million. Depreciation and amortization on our property and equipment for the six months ended June 30, 2016 and 2015 was $3.7 million and $4.7 million.

Goodwill and Intangible Assets

Activity related to goodwill for the six months ended June 30, 2016 and 2015 is as follows (in thousands):



	June 30, 2016		December 31, 2015
Balance at beginning of period	$	72	$	72
Acquisitions	1,235		—
Total goodwill	$	1,307	$	72

Purchased intangible assets, net consisted of the following (in thousands):



	June 30, 2016							December 31, 2015
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Value		Gross Carrying Amount		Accumulated Amortization			Net Carrying Value
Developed technology	$	5,050	$	—		$	5,050	$	—	$	—		$	—
Customer relationships	1,746		(1,746		)	—		1,746		(1,746		)	—
Patent	1,436		(707		)	$	729	1,436		(641		)	795
Total	$	8,232	$	(2,453	)	$	5,779	$	3,182	$	(2,387	)	$	795

Total future amortization expense for purchased intangible assets that have finite lives, based on our existing intangible assets and their current estimated useful lives as of June 30, 2016, is as follows (in thousands):



Fiscal Years Ending December 31,
Remainder of 2016	$	571
2017	1,143
2018	1,143
2019	1,143
2020	1,143
Thereafter	636
Total	$	5,779

Accrued Liabilities

Accrued liabilities as of June 30, 2016 and December 31, 2015 consists of the following (in thousands):



	June 30, 2016		December 31, 2015
Accrued compensation and benefits	$	19,808	$	18,134
Accrued tax liabilities	2,062		4,520
Other	6,960		5,103
Total accrued liabilities	$	28,830	$	27,757

Deferred Revenue

Deferred revenue as of June 30, 2016 and December 31, 2015 consists of the following (in thousands):



	June 30, 2016			December 31, 2015
Deferred revenue:
Products	$	2,699		$	3,233
Services	73,064			69,571
Total deferred revenue	75,763			72,804
Less: current portion	(51,384		)	(49,572		)
Non-current portion	$	24,379		$	23,232