Enterasys Networks CSX6000 - Manual (Page 331)

Central Site Remote Access Switch 331
C ONFIGURING IPX
IPX Routing Protocols
RIP/SAP N UMBER OF T ABLE E NTRIES
Specifies the maximum number of routing entries which can be stored in the route or service table.
You may select a number between 20 and 3072. The default value is 282 (141 routes + 141 services).
IPX R OUTING P ROTOCOL B ACKGROUND I NFORMATION
Routing Information Protocol (RIP) and Service Advertising Protocol (SAP) are used to automate
the exchange of information across a network. These discovery protocols reduce the need to
manually update routing and service tables.
IPX RIP is a protocol used to exchange routing information among IPX devices. RIP maintains a
routing table of routing information gathered across the network. RIP broadcasts this information
(either periodically or
triggered by events) to update other routers. RIP determines the fastest path
between two points on a network in terms of the number of “ticks” between those points.
IPX SAP is a protocol used to exchange service information among IPX devices. Servers use SAP
packets to advertise their particular services. Routers retrieve these packets and store them in
tables. Like RIP, routers then broadcast this service information to update other routers.
R OUTING /S ERVICE T ABLES
The system stores IPX routing information in a table. Each time a packet is received, the routing
table is referenced to determine to which network interface to forward the packet. There are three
types of routes stored in this table:
•
static
• RIP (learned)
• internal
Static routes are configured locally on the system. These routes are stored, used internally and
advertised to other routers using RIP.
RIP routes are learned from incoming RIP packets. These routes are stored, used internally and
advertised to other routers using RIP.
Internal routes are stored and used by the system exclusively. These include routes for:
•
the internal network number of this router
• the broadcast address for each IPX network interface configured
• the individual address for each IPX network interface configured
The maximum number of routes to be stored depends on the size and topology of the IPX network.
Routers in the same network may have large differences in the maximum number of routes they
store just because of their location in the network. Because of these factors, and limited memory in
the router, the maximum number of routes for each router must be configurable.
Similarly, the system also stores IPX service information in a table. Each time service information
is requested, the service table is referenced to determine the IPX address of the server. The
following service entries are stored in this table:
•
static
• SAP