Patton electronics 1082, 144, I User Manual page 9

Ethernet LAN
Figure 2. Cisco router with serial interface, configured as PPP Half-Bridge
Figure 2 shows a typical Cisco router with a serial interface configured
as a PPP Half Bridge. The router serial interface uses a remote device
that supports PPP bridging to function as a node on the remote Ethernet
network. The serial interface on the Cisco will have an IP address on the
same Ethernet subnet as the bridge.
For example, the customer site is assigned the addresses 192.168.1.0/
24 through 192.168.1.1/24. The address 192.168.1.1/24 is also the
default gateway for the remote network. The above settings remove any
routing/forwarding intelligence from the CPE. The associated Cisco con-
figuration will set serial interface (s0) to accommodate half bridging for
the above example.
Authentication is optional under PPP. In a point-to-point leased-line link,
incoming customer facilities are usually fixed in nature, therefore authen-
tication is generally not required. If the foreign device requires authenti-
cation via PAP or CHAP, the PPP software will respond with default Peer-
ID consisting of the units Ethernet MAC address and a password which
consists of the unit's Ethernet MAC address.
Some networking systems do not define network numbers in packets
sent out over a network. If a packet does not have a specific destination
network number, a router will assume that the packet is set up for the
local segment and will not forward it to any other sub-network. However,
in cases where two devices need to communicate over the wide-area,
bridging can be used to transport non-routable protocols.
Patton
1082/I
Bridge
PEC device with
serial interface
Patton 1082/C
connected to a router
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