E-12 Cisco BPX 8600 Series Reference
local addressing
A frame relay addressing convention that uses the DLCI to identify the IPX frame relay port at
the interface between the user device and the frame relay network. In local addressing, a
particular DLCI is used only at the local FR connection. The DLCI may be reused at any other
IPX node in the network.
local alarm
An IPX alarm indicating that the associated T1 line is down due to a local failure of its receive
path.
local bus
An IPX utility bus (LB/0 or LB/1) located on the midplane, which provides the electrical
connections between various front and back cards. For example, the front and back cards of the
Low Speed Data PAD group (LDP and LDI) plug into this utility bus.
logical port
A frame relay circuit consisting of either 1, 6, 24 (T1,) or 31 (E1) contiguous DSO's on a T1 or
E1 physical port.
M
major alarm
A local or remote failure that is affecting operation of the network.
MBS (Maximum Burst Size)
Maximum number of cells which may burst at the PCR but still be compliant.
MCR (Minimum Cell Rate)
The minimum cell rate that is supported by an ATM connection for an ABR connection.
MIR (Minimum Information Rate)
The minimum information rate that is supported by a frame relay connection.
minor alarm
A local or remote failure that is not affecting operation of the network, but nonetheless should be
investigated.
MUXBUS
A high-speed IPX backplane bus that carries data and timing between card slots for both circuit
line and packet line data. Consists of the TDM bus carrying the data and the system clock bus
that is used to synchronize all data flowing on and off the TDM bus.
N
n+1 redundancy
A redundancy method in which a group of cards share the same standby redundant card.
Network-to-Network Interface (NNI)
The protocol at a frame relay port that serves as a bidirectional interface between a local Cisco
WAN switching network and a separate and independent “other” network.
