Novell NETWARE 6, Руководство пользователя

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Internetwork Packet Exchange
Internetwork Packet Exchange
103-000176-001
August 29, 2001
Novell Confidential
Manual 99a
38
July 17, 2001
For example, two routers running NLSP at their respective WAN
interfaces automatically use the WAN NLSP routing type over the
connection.
Š Whether a third-party router is running at the other end of the connection
Some third-party routers might support only Numbered RIP connections
for IPX routing over WANs.
Š Whether the WAN call destination is configured as a permanent call or an
on-demand call
WAN NLSP, Unnumbered RIP, and Numbered RIP operate only over
permanent calls; the On-Demand routing type operates only over on-
demand calls.
Static Routes and Services
A static route is a RIP route that is added to the Routing Information Table by
a network administrator, rather than by the active routing protocol—in this
case, RIP—operating over a network link. For a WAN connection, a static
route comprises a WAN call destination, the destination IPX network number,
and the route metrics (hops and ticks) to reach the destination. A
static service
is a SAP service that is also added manually rather than dynamically by SAP.
A static service comprises a WAN call destination; the service name and type;
the service address network, node, and socket; and the service metrics (hops
and ticks) to reach the destination advertising the service. With the routing
software, you can configure static routes and services for both permanent and
on-demand calls.
When used with permanent calls, static routes and services are useful for
redirecting traffic to a particular network, perhaps for security reasons, and for
conserving bandwidth on slow or low-capacity links. A single static route is
also useful as a default route. In this way, the only routing information
crossing the link is that required by users to access a specified set of services.
When used with on-demand calls, static routes and services are useful for
connections that use expensive telecommunications carriers and for slow links
over which it is undesirable to exchange routing and service information.
Consider an internetwork that connects tens to hundreds of branch offices to a
single main office. Typically, each branch office requires periodic access to
information at the main office. However, it is most likely that the main office
periodically polls the branch offices to get up-to-date information, such as the
day's sales figures. Because a permanent call to each branch office is not