v3.26.1
REVENUE RECOGNITION (Tables)
3 Months Ended
Mar. 31, 2026
REVENUE RECOGNITION  
Schedule of timing of performance obligation

  ​ ​ ​

When Performance Obligation is Typically 

  ​ ​ ​

Performance Obligation

Satisfied

When Payment is Typically Due

Software and Product Revenue

Software licenses (perpetual or term)

 

For perpetual licenses, typically when made available for download (point in time); for term-based licenses, at the beginning of the specified term (point in time)

 

Generally, within 30-60 days of invoicing, except for term licenses which may be paid for over time

Software licenses (subscription)

 

Upon activation of hosted site (over time)

Generally, within 30-60 days of invoicing

Hardware

 

When control of the hardware passes to the customer; typically, upon delivery (point in time)

 

Generally, within 30-60 days of invoicing

Software upgrades

 

Upon transfer of control; typically, when made available for download (point in time)

 

Generally, within 30-60 days of invoicing

Customer Support Revenue

 

  ​

 

  ​

Customer support

 

Ratably over the course of the support contract (over time)

 

Generally, within 30-60 days of invoicing

Professional Services

 

  ​

 

  ​

Other professional services (excluding training services)

 

As work is performed (over time), typically on the input method based on hours incurred

 

Generally, within 30-60 days of invoicing (upon completion of services)

Training

 

As the training is delivered (over time), typically one to five days

 

Generally, within 30-60 days of services being performed

Schedule of disaggregation of revenue

  ​ ​ ​

  ​ ​ ​

Service revenue

  ​ ​ ​

Product

Service revenue

(professional

Three months ended March 31, 2026

revenue

(maintenance)

services)

Total revenue

United States

$

20,941

$

33,733

$

17,904

$

72,578

Europe, Middle East and Africa

16,962

14,683

7,425

39,070

Asia Pacific

27,934

9,230

3,763

40,927

Other

2,277

6,021

1,733

10,031

$

68,114

$

63,667

$

30,825

$

162,606

  ​ ​ ​

  ​ ​ ​

Service revenue

  ​ ​ ​

Product

Service revenue

(professional

Three months ended March 31, 2025

revenue

(maintenance)

services)

Total revenue

United States

$

29,341

$

33,324

$

20,030

$

82,695

Europe, Middle East and Africa

 

19,460

 

17,383

 

8,656

 

45,499

Asia Pacific

 

31,039

 

9,400

 

2,740

 

43,179

Other

 

2,151

 

6,315

 

1,440

 

9,906

$

81,991

$

66,422

$

32,866

$

181,279

The Company’s product revenue from its direct sales program and from indirect sales through its channel partner program for the three months ended March 31, 2026 and 2025 was as follows (in thousands):

Three months ended

March 31, 

March 31, 

2026

  ​ ​ ​

2025

Indirect sales through channel partner program

$

19,329

$

22,735

Direct sales

 

48,785

 

59,256

$

68,114

$

81,991

The Company’s product revenue from sales to enterprise customers and from sales to service provider customers for the three months ended March 31, 2026 and 2025 was as follows (in thousands):

Three months ended

March 31, 

March 31, 

2026

  ​ ​ ​

2025

Sales to enterprise customers

$

21,516

$

23,232

Sales to service provider customers

 

46,598

 

58,759

$

68,114

$

81,991

The Company’s product revenue and service revenue components by segment for the three months ended March 31, 2026 and 2025 were as follows (in thousands):

Three months ended

March 31, 

March 31, 

2026

  ​ ​ ​

2025

Product revenue:

Cloud and Edge

$

26,259

 

$

31,861

IP Optical Networks

41,855

 

50,130

Total product revenue

$

68,114

 

$

81,991

Service revenue:

  ​

 

  ​

Maintenance:

  ​

 

  ​

Cloud and Edge

$

50,232

 

$

50,768

IP Optical Networks

13,435

 

15,654

Total maintenance revenue

63,667

 

66,422

Professional services:

  ​

 

  ​

Cloud and Edge

23,021

 

24,962

IP Optical Networks

7,804

 

7,904

Total professional services revenue

30,825

 

32,866

Total service revenue

$

94,492

 

$

99,288

Schedule of customer assets and liabilities

The changes in the Company’s accounts receivable, unbilled receivables and deferred revenue balances for the three months ended March 31, 2026 were as follows (in thousands):

Unbilled

Deferred

Deferred

Accounts

accounts

revenue

revenue

receivable

  ​ ​ ​

receivable

  ​ ​ ​

(current)

  ​ ​ ​

(long-term)

Balance at January 1, 2026

$

161,007

$

70,878

$

124,425

$

31,654

Increase (decrease), net

 

(19,051)

 

(8,776)

 

(1,806)

 

769

Balance at March 31, 2026

$

141,956

$

62,102

$

122,619

$

32,423