Enterasys csx200 Manual Do Utilizador

CSX200 Installation Guide

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The CSX200 uses the Spanning Tree Algorithm to prevent data loops and duplicate data. This is a 
self-learning bridge, i.e., the bridge builds and updates an address table with each MAC source 
address and associated information when the packets are received.

IP routing support provides the ability to process

 frames at the network 

layer for routing. IP routing support includes the Routing Information Protocol (RIP) that allows 
the exchange of routing information on a TCP/IP network. The CSX200 receives and rebroadcasts 
RIP messages to and from adjacent routers and workstations.

Internet Packet Exchange (IPX) routing support provides the ability to process 

Novell proprietary frames at the network layer for routing. IPX routing support includes both 
Routing Information Protocol (RIP), and Service Advertising Protocol (SAP). These protocols 
allow the exchange of routing information on a Novell NetWare network. The SAP protocol 
provides a means for routers and workstations to advertise their class of services (file, print, etc.) to 
adjacent routers and workstations.

Filtering is used to allow efficient usage of network resources and provide security for your 
network and hosts. 

The CSX200 supports IP Internet Firewall filtering to prevent 

unauthorized access to your system and network resources from the Internet or a corporate 
Intranet. Security can be configured to permit or deny IP traffic. The security is established by 
configuring IP access filters, which are based on source IP address, source mask, destination IP 
address, destination mask, protocol type, and application port identifiers for both Transmission 
Control Protocol (TCP) and User Datagram Protocol (UDP).

IP access filters allow individual IP source and destination pair filtering as well as IP address 
ranges and wild carding to match any IP address. Firewall filters can be defined to allow inbound 
only, outbound only, or bi-directional IP communication up to the UDP and TCP application port 
level. The CSX200 supports the IP Access Control (from the ctip-mib) Internet Firewall Filter.

Bridge filtering lets a network administrator control the flow of packets 

across the CSX200. Bridge filtering is used to “deny” or “allow” packets based on a “matched 
pattern” using a specified position and hexadecimal content within the packet. This enables 
restricting or forwarding of messages based on address, protocol, or data content. Common uses 
include preventing access to remote networks, controlling unauthorized access to the local 
network, and limiting unnecessary traffic.