ADTRAN Total Access OC-3 L3, Установка и эксплуатация

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61181031L3-5A A-3
MUX Provisioning Data
System-level provisioning defines the following param-
eters for the network layer of the protocol stack:
• NSAP Area Address
• System ID
• TL1 Target ID
These parameters are maintained in non-volatile
storage, enabling them to survive initializations.
Restoring factory defaults has “no effect” on these
parameters. These parameters are linked to the mate
MUX.
There are no MIB objects for these parameters; they
cannot be set remotely via SNMP.
NSAP Area Address
There is no default for the NSAP Area Address; it must
be entered during the turnup process. The NSAP Area
Address may be changed as often as desired during the
turnup process without having to reboot to effect the
change. The “DCC Operation” section explains how to
change the area address once the OSI stack has been
started.
System ID
There is no default for the System ID. It must be entered
during the turnup process. The System ID is 12 hex
characters. The value entered is validated according to
the format specified in GR-253-CORE. Since system
IDs must be unique in a routing area, changing the
system ID once it is provisioned is not recommended.
Tl1 Target ID
The TL1 Target ID is provided by the SCU. It is learned
during the initialization process. It is equivalent to the
CLLI code provisioned on the SCU.
Data Link Provisioning
Data link provisioning defines parameters for the data
link layer of the protocol stack.
DCC Mode
Only the DCC Mode can be set. The DCC Mode is Link
Provisioned. Changes to DCC Mode will be sent to the
linked MUX. The DCC Mode parameter has three
possible values:
• Disabled
• User
• Network
If SDCC communications are not needed, the DCC
mode should be set to “Disabled.” The central office
side of the data link is typically the Network side. The
customer premises equipment side of the data link is
typically the User side. The default value for the OC-3
data link is “User.”
NOTE
The parameter can be changed at any time.
However, to change from Network to User or
vice versa, the parameter must first be changed
to “Disabled.”
Other data link layer parameters exist but are only
displayed for information purposes.
Information Transfer Services
For information transfer service in point-to-point data
link connections, the communication between peers can
be acknowledged (AITS) or unacknowledged (UITS).
This release only supports AITS.
AITS establishes a connection with its peer. All data
packets are sent in information frames and are acknowl-
edged by the peer. Lost packet recovery is handled by
the data link.
UITS sends data packets in unacknowledged infor-
mation frames (datagrams). There is no easy way of
knowing if the packet reached the peer; therefore,
higher protocol layers must handle lost packet recovery.
The following parameters are related to information
Transfer Services:
Window Size
This parameter identifies the maximum number of
sequentially numbered I-frames that may be
outstanding (that is, unacknowledged) at any given
time.
Maximum Retransmissions (N200)
In AITS mode, this parameter determines the maximum
number of times a frame will be transmitted without an
acknowledgement being received.
Maximum Frame Size (N201)
This parameter identifies the maximum number of
octets that can occur in an information frame. Infor-
mation frames that exceed this value will be discarded
(set to 576 bytes).