REVENUE - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2021	Aug. 01, 2020	Jul. 31, 2021	Aug. 01, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 988,141	$ 976,712	$ 2,579,198	$ 2,703,677
Products and services at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	811,598	821,816	2,081,549	2,246,782
Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	176,543	154,896	497,649	456,895
Converged Packet Optical
Disaggregation of Revenue [Line Items]
Total revenue	712,906	722,512	1,798,888	1,968,355
Routing and Switching
Disaggregation of Revenue [Line Items]
Total revenue	69,698	79,756	197,632	211,432
Platform Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	56,945	46,422	163,472	143,295
Blue Planet Automation Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	16,607	11,297	57,499	41,779
Maintenance Support and Training
Disaggregation of Revenue [Line Items]
Total revenue	74,006	69,099	212,054	202,370
Installation and Deployment
Disaggregation of Revenue [Line Items]
Total revenue	46,653	39,798	124,263	108,994
Consulting and Network Design
Disaggregation of Revenue [Line Items]
Total revenue	11,326	7,828	25,390	27,452
Networking Platforms
Disaggregation of Revenue [Line Items]
Total revenue	782,604	802,268	1,996,520	2,179,787
Networking Platforms | Products and services at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	782,604	802,268	1,996,520	2,179,787
Networking Platforms | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Networking Platforms | Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	782,604	802,268	1,996,520	2,179,787
Networking Platforms | Operating Segments | Converged Packet Optical
Disaggregation of Revenue [Line Items]
Total revenue	712,906	722,512	1,798,888	1,968,355
Networking Platforms | Operating Segments | Routing and Switching
Disaggregation of Revenue [Line Items]
Total revenue	69,698	79,756	197,632	211,432
Networking Platforms | Operating Segments | Platform Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Networking Platforms | Operating Segments | Blue Planet Automation Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Networking Platforms | Operating Segments | Maintenance Support and Training
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Networking Platforms | Operating Segments | Installation and Deployment
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Networking Platforms | Operating Segments | Consulting and Network Design
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Platform Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	56,945	46,422	163,472	143,295
Platform Software and Services | Products and services at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	17,928	15,838	54,756	45,930
Platform Software and Services | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	39,017	30,584	108,716	97,365
Platform Software and Services | Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	56,945	46,422	163,472	143,295
Platform Software and Services | Operating Segments | Converged Packet Optical
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Platform Software and Services | Operating Segments | Routing and Switching
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Platform Software and Services | Operating Segments | Platform Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	56,945	46,422	163,472	143,295
Platform Software and Services | Operating Segments | Blue Planet Automation Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Platform Software and Services | Operating Segments | Maintenance Support and Training
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Platform Software and Services | Operating Segments | Installation and Deployment
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Platform Software and Services | Operating Segments | Consulting and Network Design
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Blue Planet Automation Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	16,607	11,297	57,499	41,779
Blue Planet Automation Software and Services | Products and services at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	4,558	410	20,497	8,891
Blue Planet Automation Software and Services | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	12,049	10,887	37,002	32,888
Blue Planet Automation Software and Services | Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	16,607	11,297	57,499	41,779
Blue Planet Automation Software and Services | Operating Segments | Converged Packet Optical
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Blue Planet Automation Software and Services | Operating Segments | Routing and Switching
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Blue Planet Automation Software and Services | Operating Segments | Platform Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Blue Planet Automation Software and Services | Operating Segments | Blue Planet Automation Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	16,607	11,297	57,499	41,779
Blue Planet Automation Software and Services | Operating Segments | Maintenance Support and Training
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Blue Planet Automation Software and Services | Operating Segments | Installation and Deployment
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Blue Planet Automation Software and Services | Operating Segments | Consulting and Network Design
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Global Services
Disaggregation of Revenue [Line Items]
Total revenue	131,985	116,725	361,707	338,816
Global Services | Products and services at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	6,508	3,300	9,776	12,174
Global Services | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	125,477	113,425	351,931	326,642
Global Services | Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	131,985	116,725	361,707	338,816
Global Services | Operating Segments | Converged Packet Optical
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Global Services | Operating Segments | Routing and Switching
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Global Services | Operating Segments | Platform Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Global Services | Operating Segments | Blue Planet Automation Software and Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0	0	0
Global Services | Operating Segments | Maintenance Support and Training
Disaggregation of Revenue [Line Items]
Total revenue	74,006	69,099	212,054	202,370
Global Services | Operating Segments | Installation and Deployment
Disaggregation of Revenue [Line Items]
Total revenue	46,653	39,798	124,263	108,994
Global Services | Operating Segments | Consulting and Network Design
Disaggregation of Revenue [Line Items]
Total revenue	$ 11,326	$ 7,828	$ 25,390	$ 27,452