Multi-Tech Systems MTASR1-100 - Manual (Page 66)

MTASR1-100 Owner’s Manual
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The Tilda (~) signifies a dealy of 0.5 seconds before transmission of the reset. Consective tildas increase the
delay (i.e., ~~ equals one second). The caret (^) signifies a control character (i.e., ^M means Control M or
carriage return).
The string <BREAK> signifies that a break signal will be sent to the current communications port.
5.2.11 Frame Relay Setup
This dialog box lets you define the Frame Relay parameters. Frame Relay and PPP can not be enabled at the
same time. If Frame Relay is enabled, then PPP button is grayed out so that it can not be enabled.
Frame Relay is a multiplexing protocol designed to operate over transmission facilities that are virtually error
free. In Frame Relay, frames are routed through the network on the basis of an attached label called a Data
Link Connection Identifier (DLCI). Frame Relay combines the bandwidth efficiency of packet switching with
end-to-end protocol transparency and increased speed and performance.
The DLCI is the identification of a particular logical link in the Frame Relay network and has local significance
only. As the logical link traverses the Frame Relay network, input DLCI will be mapped to an output DLCI at
every node. Access DLCIs for permanent logical links are assigned at subscription time. Trunk DLCIs are
allocated dynamically. The valid value for a DLCI ranges from 16 to 1007.
Maximum Frame Size
This parameter displays the maximum allowable frame size. This parameter is a display type only.
Recommended Value: 1600
Management Type
The Management Interface can be either Annex D or Local Management Interface (LMI). Selection between
these two depends on the configuration of the Frame Relay supporting network. Depending on this selection
other parameters can be modified.
Annex (Annexure) D provides additional procedures for permanent virtual connections using unnumbered
information frames. Annex D describes the means for notification of outage of a permanent virtual connection
and recovery from such a condition. This follows the ANSI T1.617 standards.
LMI describes a protocol and associated procedures operating on the local interface between the user and the
network. It notifies the user of the addition, deletion, and presence of the Phased Lock Loop (PLL) in the
network. It also notifies the user of the end-to-end availability or unavailability of a PLL. Basic LMI protocol is
based on synchronous polling scheme where the user polls the network to obtain status information on the
PLLs configured on the interface. LMI simply augments the ANSI/CCITT standard Frame Relay protocol and
in no way interferes with the normal operation of user PLLs on the interface.
Annex D
When Annex D is chosen, the following parameters can be modified.