Connected: An Internet Encyclopedia
4.1. State Transition Table

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4.1. State Transition Table

4.1. State Transition Table

The complete state transition table follows. States are indicated horizontally, and events are read vertically. State transitions and actions are represented in the form action/new-state. Multiple actions are separated by commas, and may continue on succeeding lines as space requires; multiple actions may be implemented in any convenient order. The state may be followed by a letter, which indicates an explanatory footnote. The dash ('-') indicates an illegal transition.

      | State
      |    0         1         2         3         4         5
Events| Initial   Starting  Closed    Stopped   Closing   Stopping
------+-----------------------------------------------------------
 Up   |    2     irc,scr/6     -         -         -         -
 Down |    -         -         0       tls/1       0         1
 Open |  tls/1       1     irc,scr/6     3r        5r        5r
 Close|    0       tlf/0       2         2         4         4
      |
  TO+ |    -         -         -         -       str/4     str/5
  TO- |    -         -         -         -       tlf/2     tlf/3
      |
 RCR+ |    -         -       sta/2 irc,scr,sca/8   4         5
 RCR- |    -         -       sta/2 irc,scr,scn/6   4         5
 RCA  |    -         -       sta/2     sta/3       4         5
 RCN  |    -         -       sta/2     sta/3       4         5
      |
 RTR  |    -         -       sta/2     sta/3     sta/4     sta/5
 RTA  |    -         -         2         3       tlf/2     tlf/3
      |
 RUC  |    -         -       scj/2     scj/3     scj/4     scj/5
 RXJ+ |    -         -         2         3         4         5
 RXJ- |    -         -       tlf/2     tlf/3     tlf/2     tlf/3
      |
 RXR  |    -         -         2         3         4         5

      | State
      |    6         7         8           9
Events| Req-Sent  Ack-Rcvd  Ack-Sent    Opened
------+-----------------------------------------
 Up   |    -         -         -           -
 Down |    1         1         1         tld/1
 Open |    6         7         8           9r
 Close|irc,str/4 irc,str/4 irc,str/4 tld,irc,str/4
      |
  TO+ |  scr/6     scr/6     scr/8         -
  TO- |  tlf/3p    tlf/3p    tlf/3p        -
      |
 RCR+ |  sca/8   sca,tlu/9   sca/8   tld,scr,sca/8
 RCR- |  scn/6     scn/7     scn/6   tld,scr,scn/6
 RCA  |  irc/7     scr/6x  irc,tlu/9   tld,scr/6x
 RCN  |irc,scr/6   scr/6x  irc,scr/8   tld,scr/6x
      |
 RTR  |  sta/6     sta/6     sta/6   tld,zrc,sta/5
 RTA  |    6         6         8       tld,scr/6
      |
 RUC  |  scj/6     scj/7     scj/8       scj/9
 RXJ+ |    6         6         8           9
 RXJ- |  tlf/3     tlf/3     tlf/3   tld,irc,str/5
      |
 RXR  |    6         7         8         ser/9

The states in which the Restart timer is running are identifiable by the presence of TO events. Only the Send-Configure-Request, Send- Terminate-Request and Zero-Restart-Count actions start or re-start the Restart timer. The Restart timer is stopped when transitioning from any state where the timer is running to a state where the timer is not running.

The events and actions are defined according to a message passing architecture, rather than a signalling architecture. If an action is desired to control specific signals (such as DTR), additional actions are likely to be required.

[p] Passive option; see Stopped state discussion.

[r] Restart option; see Open event discussion.

[x] Crossed connection; see RCA event discussion.


Next: 4.2. States

Connected: An Internet Encyclopedia
4.1. State Transition Table

 


Dies ist ein Mirror von Connected: An Internet Encyclopedia von Brent Baccala. Die offizielle Projekt-Homepage findet sich im Web unter www.freesoft.org/CIE. Dieser Mirror wurde zuletzt aktualisiert am Samstag, 28 Januar 2006 18:17 +0100.