Publication: Magyar Közlöny
Issue: MK-2007-70 (Year: 2007, Number: 70)
Era: 2004-2010
Section: Melléklet a 2007. évi XLVI. törvényhez
Paragraph Index: 4302

c) sending Mode S CLEAR REQUEST packets for these SVCs to the DCE (via the reformatting process) for transfer to the DTE. Note.— This action will allow all ISO 8208 SVCs attached to the Mode S SVCs to be cleared and return to their ready states (p1). 5.2.6.3.4 Clear confirmation. When the XDCE receives a Mode S CLEAR CONFIRMATION packet, the remaining allocated resources to manage the SVC shall be released (including the resequencing buffers) and the SVC shall be returned to the p1 state. Mode S CLEAR CONFIRMATION packets shall not be transferred to the reformatting process. 2007/70/II. szám Annex 10 — Aeronautical Telecommunications Volume III 5-22 28/11/02 No. 77 5.2.6.3.5 Clear collision. A clear collision occurs at the XDCE when it receives a Mode S CLEAR REQUEST packet from the DCE (via the reformatting process) and then receives a Mode S CLEAR REQUEST packet from the peer XDCE (or vice versa). In this event, the XDCE does not expect to receive a Mode S CLEAR CONFIRMATION packet for this SVC and shall consider the clearing complete. 5.2.6.3.6 Packet processing. The XDCE shall treat an Sbit sequence of Mode S CALL REQUEST, CALL ACCEPT and CLEAR REQUEST packets as a single entity. 5.2.6.4 DATA TRANSFER AND INTERRUPT PROCEDURES 5.2.6.4.1 GENERAL PROVISIONS 5.2.6.4.1.1 Data transfer and interrupt procedures shall apply independently to each SVC. The contents of the user data field shall be passed transparently to the DCE or to the peer XDCE. Data shall be transferred in the order dictated by the sequence numbers assigned to the data packets. 5.2.6.4.1.2 To transfer DATA packets, the SVC shall be in a FLOW CONTROL READY state (d1). 5.2.6.4.2 MODE S PACKET SIZE 5.2.6.4.2.1 The maximum size of Mode S packets shall be 152 bytes in the uplink direction and 160 bytes in the downlink direction for installations that have full uplink and downlink ELM capability. The maximum downlink packet size for level four transponders with less than 16 segment downlink ELM capability shall be 10 bytes times the maximum number of downlink ELM segments that the transponder specifies in its data link capability report. If there is no ELM capability, the maximum Mode S packet size shall be 28 bytes. 5.2.6.4.2.2 The Mode S subnetwork shall allow packets of less than the maximum size to be transferred. 5.2.6.4.3 FLOW CONTROL WINDOW SIZE 5.2.6.4.3.1 The flow control window size of the Mode S subnetwork shall be independent of that used on the DTE/DCE interface. The Mode S subnetwork window size shall be 15 packets in the uplink and downlink directions. 5.2.6.4.4 SVC FLOW CONTROL 5.2.6.4.4.1 Flow control shall be managed by means of a sequence number for received packets (PR) and one for packets that have been sent (PS). A sequence number (PS) shall be assigned for each Mode S DATA packet generated by the XDLP for each SVC. The first Mode S DATA packet transferred by the XDCE to frame processing when the SVC has just entered the flow control ready state shall be numbered zero. The first Mode S packet received from the peer XDCE after an SVC has just entered the flow control ready state shall be numbered zero. Subsequent packets shall be numbered consecutively. 5.2.6.4.4.2 A source of Mode S DATA packets (the ADCE or GDCE) shall not send (without permission from the receiver) more Mode S DATA packets than would fill the flow control window. The receiver shall give explicit permission to send more packets. 5.2.6.4.4.3 The permission information shall be in the form of the next expected packet sequence number, and shall be denoted PR. If a receiver wishes to update the window and it has data to transmit to the sender, a Mode S DATA packet shall be used for information transfer. If the window must be updated and no data are to be sent, a Mode S RECEIVE READY (RR) or Mode S RECEIVE NOT READY (RNR) packet shall be sent. At this point, the “sliding window” shall be moved to begin at the new PR value. The XDCE shall now be authorized to transfer more packets without acknowledgement up to the window limit. 5.2.6.4.4.4 When the sequence number (PS) of the next Mode S DATA packet to be sent is in the range PR < PS < PR + 14 (modulo 16), the sequence number shall be defined to be “in the window” and the XDCE shall be authorized to transmit the packet. Otherwise, the sequence number (PS) of the packet shall be defined to be “outside the window” and the XDCE shall not transmit the packet to the peer XDCE. 5.2.6.4.4.5 When the sequence number (PS) of the packet received is next in sequence and within the window, the XDCE shall accept this packet. Receipt of a packet with a PS:

Source: https://magyarkozlony.hu/hivatalos-lapok/4c6310a937d14bac566ee9c9d944896656c292dd/dokumentumok/5a6ac3c6db12e692ae41096677ad5f072d2cc9f3/letoltes