Juniper J4350, Getting Started Manual

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J4350 and J6350 Services Router Getting Started Guide
Table 13: PIM Terms (continued)
Term Definition
ADSL 2/2+ Annex B ITU-T Standard G.992.1 that defines how ADSL works over Integrated Services Digital
Network (ISDN) lines.
bandwidth on demand ISDN cost-control feature defining the bandwidth threshold that must be reached
on all links before a Services Router initiates additional ISDN data connections to
provide more bandwidth.
basic rate interface (BRI) ISDN interface intended for home and small enterprise applications. BRI consists of
two 64-Kbps B-channels and one 16-Kbps D-channel.
callback Alternative feature to dial-in that enables a J-series Services Router to call back the
caller from the remote end of a backup ISDN connection. Instead of accepting a call
from the remote end of the connection, the router rejects the call, waits a configured
period of time, and calls a number configured on the router’s dialer interface. See
also
dial-in .
caller ID Telephone number of the caller on the remote end of a backup ISDN connection,
used to dial in and also to identify the caller. Multiple caller IDs can be configured on
an ISDN dialer interface. During dial-in, the router matches the incoming call’s caller
ID against the caller IDs configured on its dialer interfaces. Each dialer interface
accepts calls from only callers whose caller IDs are configured on it.
channel service unit (CSU) Unit that connects a digital telephone line to a multiplexer or other signal service.
data service unit (DSU) Unit that connects a data terminal equipment (DTE) device—in this case, a Services
Router—to a digital telephone line.
data terminal
equipment–to–data
communication
equipment (DTE–DCE)
interface Interface that a Services Router (the DTE) uses to exchange information with a serial
device such as a modem (the DCE).
A DTE cable uses a male 9-pin or 25-pin connector, and a DCE cable uses a female
9-pin or 25-pin connector.
demand circuit Interface configured for dial-on-demand routing backup. In OSPF, the demand circuit
reduces the amount of OSPF traffic by removing all OSPF protocols when the routing
domain is in a steady state.
dial backup Feature that reestablishes network connectivity through one or more backup ISDN
dialer interfaces after a primary interface fails. When the primary interface is
reestablished, the ISDN interface is disconnected.
dial-in Feature that enables J-series Services Routers to receive calls from the remote end
of a backup ISDN connection. The remote end of the ISDN call might be a service
provider, a corporate central location, or a customer premises equipment (CPE)
branch office. All incoming calls can be verified against caller IDs configured on the
router’s dialer interface. See also
callback .
dialer filter Stateless firewall filter that enables dial-on-demand routing backup when applied to a
physical ISDN interface and its dialer interface configured as a passive static route.
The passive static route has a lower priority than dynamic routes. If all dynamic
routes to an address are lost from the routing table and the router receives a packet
for that address, the dialer interface initiates an ISDN backup connection and sends
the packet over it. See also
dial-on-demand routing backup; floating static route .
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PIM Terms