Planning for CSX400 ISDN ConfigurationCSX400 and CSX400-DC User’s Guide 37IPX Routes — If the CSX400 is to direct traffic to network segments and servers beyond theremote router, the routing table in the CSX400 can be “seeded” with static IPX routes. An IPXroute includes a network number, hop count and ticks. The hop count is the number of routersthrough which traffic must pass to reach the remote network segment or server. Ticks representhow much time the packet takes to reach the destination in roughly 1/18th of a second increments.The CSX400 routing information table must be seeded statically so that it dials out to theappropriate remote router when IPX traffic is targeted to network segments or servers beyond thatremote router. After the link is established, RIP update packets dynamically add to the routinginformation table in the CSX400. Seeding the routing table is not necessary when a CSX400 neverdials out; it will discover routes beyond the calling router as soon as RIP updates arrive (providedthe remote router supports RIP).IPX SAPs — If the CSX400 is to obtain services beyond the remote router, the CSX400 SAPservices table must be seeded statically. A SAP service is identified by a server name andcorresponding server type, network number, node number and socket. The socket numberrepresents the service (application) within the server node.The CSX400 SAP services table must be seeded statically so that the device can direct traffic to theappropriate remote router when a service is requested from a server beyond that remote router.After the link is established, SAP broadcast packets dynamically add to the target router servicestable. Seeding the table is not necessary when a CSX400 never dials out; it will discover remoteservices beyond the calling router as soon as SAP broadcasts arrive (provided the remote routersupports IPX).IPX Network Numbers — IPX network numbers are assigned to LAN network segments as wellas servers. These numbers should be unique for all IPX networks on the Internetwork.IPX external network numbers refer to the physical LAN network segments to which servers androuters are connected. The WAN link network number is an external IPX network number. This isa unique number that you choose (or are given by the network administrator) to represent the WANlink between the CSX400 and remote router. The local Ethernet IPX network number is also anexternal network number.Servers are identified with internal network numbers. This is a logical network number thatidentifies the individual server. For a local router to access a server beyond the remote router, youspecify a route using the internal network number of a server. To seed the routing table to access anetwork segment, you specify the external network number of the LAN segment. The networknumber in the SAP table is the internal network number of the server.
