3Com 3C13636 Configuration Manual page 507

3Com Router 3000 Ethernet Family
Configuration Guide
messages, and cuts down the route finding time and improves forwarding throughput of
IP messages. Since the forwarding table in the cache has been optimized, much
quicker searching speed can be obtained.
The unicast fast forwarding implemented by V 2.41 provides:
Unicast fast forwarding on all types of high-speed link interfaces (including
subinterfaces), such as Ethernet, synchronous PPP, frame relay, and HDLC.
Unicast fast forwarding in presence of normal firewall.
Unicast fast forwarding in presence of ASPF firewall.
Unicast fast forwarding when NAT is configured.
Unicast fast forwarding when GRE is in use.
Significantly improved forwarding efficiency.
The performance of unicast fast forwarding sometimes will be affected by some
characteristics such as message queue management and message header
compression. Unicast fast forwarding is not conducted for fragmented messages.
10.7.2 Configuring Unicast Fast Forwarding
You can disable fast-forwarding as needed. For example, if load balance is required
when forwarding packets, fast-forwarding must be disabled in the forwarding direction
of the interface.
Perform the following configuration in interface view.
Table 10-7 Enable/disable unicast fast forwarding on an interface
Enable unicast fast forwarding in both directions of
the interface
Enable unicast fast forwarding on the inbound
interface
Enable unicast fast forwarding on the outbound
interface
Disable unicast fast forwarding on the interface
By default, unicast fast forwarding is enabled in the input/output directions of the
interface.
Operation
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10-6
Chapter 10 IP Performance Configuration
Command
ip fast-forwarding
ip fast-forwarding inbound
ip fast-forwarding outbound
undo ip fast-forwarding