Znyx Networks bh5700 Manuale Utente

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network-enabled Linux implementation.
The purpose of the routing table is to tell the packet forwarding software where to forward the 
data packets. In  Linux, the packet-forwarding algorithm is operated in software. Normally, the 
routing tables are maintained by operator configuration and the various routing protocols that run 
in the application environment of Linux. 
OpenArchitect uses an innovative new approach for forwarding packets. It provides embedded 
software daemons that replicate ( shadow) the Linux routing tables in the silicon-based 
forwarding tables (see Figure 1.1: Fabric Switch Elements). In the  OpenArchitect switching 
environment, the switching chips do the real-time work in switching network packets. The switch 
fabric consults its own forwarding tables for each incoming packet; and either filters or forwards 
the packet to any egress port, the embedded CPU, or to any combination. The Linux routing 
tables, running in software, are used to update the silicon-based tables. This provides both the 
flexibility and control of the Linux software environment and the speed of dedicated switching 
silicon.
The OpenArchitect environment includes additional features. For example, installing the 
OpenArchitect switch gives you immediate implementation of Linux routing protocols. Also, you 
have complete support of routing table updates and a standardized method for configuration. 
Finally, you can quickly integrate bug fixes, protocol enhancements and additional protocol 
implementations from the Linux community. You can also integrate OpenArchitect into other 
Linux applications including VPN software, voice over IP protocols, Quality of Service, and 
HTML configuration.
RAIN Management API (RMAPI)  is a generic interface for passing control data. The 
OpenArchitect libraries are implemented completely above RMAPI. The libraries provide a front-
end to RMAPI to simplify application writing. Currently one library is implemented, a general 
library called zlxlib. As the OpenArchitect application requirements grow, the existing library 
will be expanded and additional libraries will be created.  
Ethernet Switch Blade User's Guide
release  3.2.2j
page 21