Endace DAG 3.7G Series, Руководство пользователя

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EDM01-07: DAG 3.7G Card User Guide
Version 7: May 2006 16 ©2005
In-Line
Forwarding
The DAG 3.7G card can be used as an 'inline' device to receive, inspect, filter
and forward packets between Port A and Port B.
The following information describes the DAG 3.7G card inline forwarding
process.
Process Description
Inline transmission. This operation can be performed at 100% line rate in
both directions simultaneously. A PCI-X 133MHz
slot is required for full performance and the
performance may be limited by the host PC CPU
and memory performance.
dagfwddemo
Program.
The
dagfwddemo
program is provided as a
demonstration of how this can be achieved. This
program forwards packets bidirectionally, applying a
user supplied BPF filter to each packet with the host
CPU. Packets which match the filter are forwarded,
while packets that do not match are dropped.
This is intended as a demonstration of Inline
Forwarding technology for use in Firewall or
IDS/IPS applications. It is not suitable for use as a
production Firewall.
Modification of
packets.
Modification of packets during inspection is also
possible. The modifications should not change the
length of the packet, and the user is responsible for
re-computing checksums as needed.