HP 600 Series, Services And Applications

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How It Works
Synchronous ports on HP routers are used to provide the sync pass-through
capability. Sync pass-through circuits are configured on the HP router using
the point-to-point circuit type and the pass-through data-link-layer protocol.
Once pass-through has been selected, the router software ignores the other
circuit parameters. Additionally, the local and remote station addresses
(MAC addresses) must be configured for sync pass-through to operate. Sync
pass-through thus connects a device attached to one synchronous port on an
HP router to another device attached to another router’s synchronous port.
Sync pass-through traffic is conveyed through the extended LAN by the
bridging service. Station addresses are assigned to sync pass-through ports
by the user. In figure 1, station addresses are assigned to each of the synchro-
nous circuits marked with a circled number. When configuring the site C sync
pass-through interface, for example, the station address assigned to the local
sync pass-through circuit (marked
②
) is entered as the local LAN address.
The station address assigned to the sync pass-through interface at site A
(also marked
②
) is entered as the remote LAN address.
Figure 2 shows another sync pass-through application. Sync pass-through is
used to provide communication for a private X.25 network. Host A communi-
cates with host B using the X.25 packet switches attached to the synchro-
nous ports at site A and site B. The router ports labeled
①
convey this
switch-to-switch traffic.
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Using Synchronous Pass-Through to Consolidate Synchronous Traffic
How It Works
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