曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
receiver shall receive before it generates an RR packet.
Parameter A shall not be separately negotiated, but be set to
the smallest integer greater than or equal to the value of onehalf
of parameter W.
Note.- The purpose of the acknowledgment window is to
reduce the probability that an explicit acknowledgement needs
to be sent. The acknowledgment ~lindow is set to one-half of
the transmir window to reduce the probabili~ thar a starinn
will go into flow control.
6.6.5 Effects of layers 1 and 2
on the subnetwork layer
The subnetwork layer virtual circuit shall be valid only on the
underlying Link layer connection over which it was established.
6.6.6 Description of procedures
Except where noted in 6.6.6.1 through 6.6.6.5, the provisions
of IS0 8208 shall apply between the aircraft DTE and the
ground DCE. If a ground DCE receives an unsupported packet
layer facility, it shall either process the CALL REQUEST
without altering the facilities or shaU send a C L M
CONFIRMATION.
6.6.6.1 Supporred facilities. Table 6-53 lists options and
facilities, documented in IS0 8208, that' shall be supported by
VDL.
6.6.6.2 Unsupported facilities. Table 6-54 lists the
facilities, documented in IS0 8208, that shall not be supported
by the VDL.
6.6.6.3 Subne fwork establishnrent ard connecnbn
munagement. l'he subnetwork establishment and connection
management options used shall be chosen as required by the
operational conditions.
6.6.6.3.1 Subr~ctwork entie initialization. The ground
DCE shall be initialised on receipt of a valid XK-CMDLE.
The aircraft DCE shall be initialised on receipt of a valid
XII-RSP-LE.
Nute.- Only the subncfivork entities correspondijig to fhe
link on which the XID-CMD-LE/XID-RSP-LE is received sill
be initialized. The entities ussigned to other links will not be
ufltcred.
6.6.6.3.2 Subnetwork connection establishment. On1 y
aircraft DTEs shall request subnetwork connection establishment
in the VDL subnetwork.
6.6.6.3.2.1 Explicit subnetwork connec-tion establishment.
Immediately after link establishment, the aircraft DTE shall
attempt to establish a subne~work connection to at least one
ground DTE. The aircraft DTE shall request a single
subnetwork connection per gmund DTE by the transmission of
a CALL REQUEST packet specifying the ground DTE
address in the Called Address field. On receipt of the CAEL
REQUEST, the ground DCE shall attempt to establish a
subnetwork connection to the specified DTE. A CALL
CONFIRMATION packet shall be sent to the aircraft DTE if
the connection is established; otherwise a CLEAR REQUEST
packet including a diagnostic specifying the cause of failure
shall be sent. The ground DCE shall use the Called Line
Address Modified Notification facility no inform the aircraft
DTE of the ground DTE's X.121 address.
Note.- The Calling Address Jidd in. CLEAR
CONFIRMATION pocket will conrain the Aircraft DTE
address.
6.6.6.3.2.2 Expedited subnetwork coranection esrablishrnent.
An aircraft LME initiating expedited subnetwork
connection establishment shall implement this section. The
aimaft LME shall invoke the procedures described in
6.5.3.4.12 when connecting to a ground LME indicating
support for expedited subnetwork connection procedures. Ttie
aircraft DTE shall reissue CALL REQUESTS for those logical
channels for which responses (i.e. either a CAEL
C0NFUWA"ION or a CLEAR REQUEST) were not included
in the XTD-RSP-LE. The ground DCE shall use the
Called Line Address Modified Notification facility to inform
the aircraft DTE of the ground DTE's X.121 address.
Note I.- The CLEAR CONFIRMATION, required. will
be transferred in an INFO frame.
Note 2.- The Calling Address field in CLEAR
CONFIRMATION packet will cunrain the Aircmfi DTE
address.
6.6.6.3.3 Subnenvork connection maintenance. During link
establishment a ground JXE shall jndjcate its available routers
in the ATN Router NETS parameter and the aircraft LME shall
then attempl to maintain all subnetwork comections.
Note.- For subnetwork conrlections to be maintained
across ground station changes, the LME gives preference in
choosing a new ground station to gmund starions indicating
accessibi1it;v to the DTEs to which subnetwork connections
already exist.
211 1/00
No. 75
Annex 10 - Aeronautical Telecommunications Volume I l l
6.6.6.3.3.1 Explicit subnetwork connectiort maintenance.
To explicitly request subnetwork connection maintenance to a
ground DTE. an aircraft DTE shall send a CALL REQUEST
packet to the ground DTE with a fast select facility containing
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
附件10--航空电信an10_v3_1ed_amend_75(114)
