SEGMENTS AND ENTITY WIDE DISCLOSURES (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Revenue:
Revenue	$ 707,022	$ 640,717	$ 1,328,519	$ 1,213,832
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	57,820	28,233	76,924	39,472
Less: Non-performance operating expenses
Selling and marketing	88,551	86,668	173,553	169,146
General and administrative	34,990	35,203	70,854	66,345
Amortization of intangible assets	10,980	15,566	25,531	32,428
Acquisition and integration costs	0	2,285	0	3,584
Restructuring costs	4,276	535	6,671	919
Add: Other non-performance financial items
Interest expense and other income (loss), net	(16,226)	(11,641)	(31,059)	(33,127)
Less: Provision for income taxes	3,568	2,595	3,978	3,894
Net income	38,026	13,997	41,887	2,451
Networking Platforms
Revenue:
Revenue	571,487	512,206	1,061,431	961,716
Networking Platforms \| Converged Packet Optical
Revenue:
Revenue	502,131	435,173	914,783	824,341
Networking Platforms \| Packet Networking
Revenue:
Revenue	66,326	68,582	138,520	116,779
Networking Platforms \| Optical Transport
Revenue:
Revenue	3,030	8,451	8,128	20,596
Software and Software-Related Services
Revenue:
Revenue	37,716	30,473	77,096	55,899
Software and Software-Related Services \| Software Platforms
Revenue:
Revenue	13,143	11,772	30,192	19,851
Software and Software-Related Services \| Software-Related Services
Revenue:
Revenue	24,573	18,701	46,904	36,048
Global Services
Revenue:
Revenue	97,819	98,038	189,992	196,217
Global Services \| Maintenance Support and Training
Revenue:
Revenue	58,241	57,069	113,231	113,127
Global Services \| Installation and Deployment
Revenue:
Revenue	28,695	30,232	56,614	61,072
Global Services \| Consulting and Network Design
Revenue:
Revenue	10,883	10,737	20,147	22,018
Operating Segments
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	196,617	168,490	353,533	311,894
Operating Segments \| Networking Platforms
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	150,464	132,606	264,210	239,588
Operating Segments \| Software and Software-Related Services
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	4,551	35,692	12,252	(3,382)
Operating Segments \| Global Services
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	$ 41,602	$ 192	$ 77,071	$ 75,688

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