SEGMENTS AND ENTITY WIDE DISCLOSURES (Details) - USD ($) $ in Thousands	3 Months Ended
Jan. 31, 2017	Jan. 31, 2016
Revenue:
Revenue	$ 621,497	$ 573,115
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	19,104	11,239
Less: Non-performance operating expenses
Selling and marketing	85,002	82,478
General and administrative	35,864	31,142
Acquisition and integration costs	0	1,299
Amortization of intangible assets	14,551	16,862
Restructuring costs	2,395	384
Add: Other non-performance financial items
Interest expense and other income (loss), net	(14,833)	(21,486)
Less: Provision for income taxes	410	1,299
Net income (loss)	3,861	(11,546)
Networking Platforms
Revenue:
Revenue	489,944	449,510
Networking Platforms \| Converged Packet Optical
Revenue:
Revenue	412,652	389,168
Networking Platforms \| Packet Networking
Revenue:
Revenue	72,194	48,197
Networking Platforms \| Optical Transport
Revenue:
Revenue	5,098	12,145
Software and Software-Related Services
Revenue:
Revenue	39,380	25,426
Software and Software-Related Services \| Software Platforms
Revenue:
Revenue	17,049	8,079
Software and Software-Related Services \| Software-Related Services
Revenue:
Revenue	22,331	17,347
Global Services
Revenue:
Revenue	92,173	98,179
Global Services \| Maintenance Support and Training
Revenue:
Revenue	54,990	56,058
Global Services \| Installation and Deployment
Revenue:
Revenue	27,919	30,840
Global Services \| Consulting and Network Design
Revenue:
Revenue	9,264	11,281
Operating segments
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	156,916	143,404
Operating segments \| Networking Platforms
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	113,747	106,982
Operating segments \| Software and Software-Related Services
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	7,700	(3,574)
Operating segments \| Global Services
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Operating income (loss)	$ 35,469	$ 39,996

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