FloodGate-1
DiffServ Support
FloodGate-1® enables extending corporate QoS requirements to the WAN by classifying traffic according to the Differentiated Services (DiffServ) standard. DiffServ support enables service providers with IP networks to offer end-to-end Quality of Service (QoS) for both VPN and unencrypted traffic. End-users in turn, can quickly realize the benefits of optimized, end-to-end network performance.How Does DiffServ Support Work?
Standalone QoS Limitations
Integrated QoS/VPN Solutions
By integrating DiffServ and VPN functionality on the same device, FloodGate-1 solves the problem described above for a standalone QoS device. With FloodGate-1, information in the DSCP field is copied to the outer IPSec header, so that DiffServ information is accessible to the service provider's edge router.
The network diagram below illustrates this process, as it applies to an MPLS network.

DiffServ in an MPLS network
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Image Detail
Note that MPLS networks provide for routing high priority traffic through a specified low latency path. Such a path is shown in the diagram, highlighted in orange.
Integrated SMART Management
Example Application
The figure below shows a FloodGate-1 DiffServ policy with four DiffServ service levels. Within each service level, each class of traffic can have QoS attributes, for shaping traffic on the local access link.

Sample FloodGate-1 Policy with
DiffServ Service Levels
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In this case, the system administrator has created a FloodGate-1
rule that classifies VoIP traffic as high priority (Gold Class)
traffic. As a result, FloodGate-1 will mark the IP header
of VoIP packets to designate that they have "Expedited
Forwarding." (This corresponds to a DSCP of 101110.)
FloodGate-1 subsequently copies this mark to the outer IPSec
header, so that the service provider's edge router can accurately
prioritize the packets.