Cabletron Systems FRM User Manual - page 82
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Frame Relay Module 4. 0 User G uide, Rev 01
Line Speed
is the data transmission rate in bits per second, and the clock speed when the port is a
physical DCE (i.e., the attached I/O cable is DCE). If this port is a physical DTE,
specify the line speed that matches (as closely as possible) that of the device connected
directly to the port.
Selecting this parameter will display a list of ranges. Press the letter corresponding to
a range to display the valid speeds within that range. All possible speeds are:
75
150
300
600
1200
2400
4800
9600
14.4K
19.2K
24K
28.8K
38.4K
48K
56K
64K
72K
112K
128K
168K
192K
224K
256K
280K
320K
336K
384K
392K
448K
504K
512K
560K
576K
616K
640K
672K
704K
728K
768K
784K
832K
840K
896K
952K
960K
1.008M
1.024M
1.064M
1.088M
1.12M
1.152M
1.176M
1.216M
1.232M
1.28M
1.288M
1.344M
1.4M
1.408M
1.456M
1.472M
1.512M
1.536M
1.568M
1.6M
1.624M
1.664M
1.668M
1.728M
1.792M
1.856M
1.92M
1.984M
2.048M
If an RS-232 DCE port is directly connected to the DTE via the standard
Cabletron cable, the maximum supported speed is 64K. If longer cabling is
used, the maximum speed is 19.2K. (The EIA standard for RS-232
addresses speeds up to 19.2 Kbps.)
Maximum Bytes per Frame
specifies the maximum size of any I-frame (Information frame) that can be transmitted
or received on the port.
Logical DCE
defines the port as (if
Y
) logical DCE or (if
N
) DTE. The port must be configured as
the opposite of the device at the other end of the connection.
Logical and physical DCE/DTE are independent of each other (e.g., a port can be a
physical DCE and logical DTE).
Generate Clock
specifies whether the port will generate the clock necessary to synchronize traffic over
the link. If the port is a physical DCE (determined by the port's I/O cable interface),
set this parameter to
Y
, since the physical DCE generates clock. If the port is DTE, set
the parameter to
N
.
Rcv Clock (TT) from DTE
allows the clock to be looped back from the DTE using the TT (Terminal Timing)
signal, which can be helpful on high-speed lines. Generally, if the local interface is
physical DCE and the line speed is above 256 Kbps, this parameter should be set to
Y
.
(Make sure the remote DTE is configured to provide the terminal timing.)
Link Layer Management
determines whether, and what type of, configurable network management (e.g., status
enquiries to the port) will be used: none, LMI (Local Management Interface), or ANSI
T1.617 Annex D (an ANSI-standard LMI).