Cisco IOS IPsec functionality provides network data encryption at the IP packet level, offering a robust security solution that is standards-based. IPsec provides data authentication and anti-replay services in addition to data confidentiality services. IPsec is the only way to implement secure virtual private networks (VPNs). Combined with other Cisco IOS Software functionality customers can build scalable, robust, and secure QoS aware VPNs relying on Cisco IOS IPsec functionality.
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