Alcatel-Lucent 6850-48 Guida Di Rete
Configuring IPX
IPX RIP/SAP Filtering
OmniSwitch AOS Release 6 Network Configuration Guide
September 2009
page 33-11
IPX RIP/SAP Filtering
The IPX RIP/SAP Filtering feature give you a means of controlling the operation of the IPX RIP/SAP
protocols. By using IPX RIP/SAP filters, you can minimize the number of entries put in the IPX RIP
Routing and SAP Bindery Tables, improve overall network performance by eliminating unnecessary traf-
fic, and control users’ access to NetWare services. For example:
protocols. By using IPX RIP/SAP filters, you can minimize the number of entries put in the IPX RIP
Routing and SAP Bindery Tables, improve overall network performance by eliminating unnecessary traf-
fic, and control users’ access to NetWare services. For example:
• RIP Input and Output filters can be used to isolate entire network segments (and/or switches) to make
the network appear differently to the different segments.
• RIP Input and Output filters can be used to reduce the amount of traffic needed to advertise routes that
should not be used by a particular network segment.
• SAP Input and Output filters can be used to improve performance by limiting the amount of SAP traf-
fic. For example, because printing is generally a local operation, there’s no need to advertise print serv-
ers to remote networks. A SAP filter can be used in this case to restrict “Print Server Advertisement”
SAPs.
ers to remote networks. A SAP filter can be used in this case to restrict “Print Server Advertisement”
SAPs.
Five types of IPX RIP/SAP filters are available:
• RIP Input Filters. Control which networks are allowed into the routing table when IPX RIP updates
are received.
• RIP Output Filters. Control the list of networks included in routing updates sent by the switch. These
filters control which networks the switch advertises in its IPX RIP updates.
• SAP Input Filters. Control the SAP updates received by the switch prior to a switch accepting infor-
mation about a service. The switch will filter all incoming service advertisements received before
accepting information about a service.
accepting information about a service.
• SAP Output Filters. Control which services are included in SAP updates sent by the switch. The
switch applies the SAP output filters prior to sending SAP packets.
• GNS Output Filters. Control which servers are included in the GNS responses sent by the switch.
All types of IPX Filters can be configured either to allow or to block traffic. The default setting for all
filters is to allow traffic. Therefore, you will typically have to define only a filter to block traffic.
However, defining a filter to allow certain traffic may be useful in situations where a more generic filter
has been defined to block the majority of the traffic. For example, you could use a filter to allow traffic
from a specific host on a network where all other traffic has been blocked. A discussion of the precedence
of “allow” filters appears later in this section. Keep in mind that precedence applies only to “allow” filters,
not to “block” filters.
filters is to allow traffic. Therefore, you will typically have to define only a filter to block traffic.
However, defining a filter to allow certain traffic may be useful in situations where a more generic filter
has been defined to block the majority of the traffic. For example, you could use a filter to allow traffic
from a specific host on a network where all other traffic has been blocked. A discussion of the precedence
of “allow” filters appears later in this section. Keep in mind that precedence applies only to “allow” filters,
not to “block” filters.
Note. You can apply filters to all router interfaces by defining a “global” filter, or you can limit the filter
to specific interfaces.
to specific interfaces.