Because encryption comes at an overhead processing cost, it should only be applied as necessary, taking into account the sensitivity of the information and application characteristics. IPSec encryption can be deployed in standalone environments between clients, routers, and firewalls or used in conjunction with L2TP tunneling in access VPNs. Scalable encryption solutions for both are available in the ISA encryption co-processor module. US federal regulations limit the export of encryption technologies, so customers outside the USA should ask their local Cisco office about availability. QoS lets service providers optimize valuable WAN bandwidth and guarantee delivery of mission-critical application traffic.
Traffic is marked before leaving the enterprise network.
Policies are applied prior to tunneling or to tunnels in the core. VPN Management and Provisioning Service providers and enterprise managers usually share management duties. While today's VPN tunnels and encryption are proven techniques and enable secure, reliable VPN services, over the long term they cannot scale to sustain the rising demand for services. Cisco is working closely with service providers to ensure a smooth transition to MPLS-enabled VPN services. MPLS works on a label-based paradigm, tagging packets as they enter the provider network to expedite forwarding through a connectionless IP core.