5.     , ,   
 .

 AX.25  NEROM         
SSID .     ,  
  .

   AX.25  NOS  BPQ  
      SSID    AX.25 
NETROM . ,    Linux   . 
       ,    .
 ,   ,       
  .

1.  AX.25  NETROM      
  SSID .

2. TCP/IP     SSID   AX.25, 
     AX.25  1- ,   - 
   .

3. NETROM     SSID ,   
  ,     ,   NETROM
    NETROM,       SSID 
  AX.25       NETROM
"".    .

4.  ROSE        
rsparms,         SSID  AX.25. 
    SSID,   rsparms,  ROSE 
    SSID   .

5.    "AX.25d"   ,  
  SSID,    .

6.     ,     
 IP    .

5.1.    T1, T2, N2  .?

        TNC,  
,    AX.25  >  TNC2  OS Linux, 
,      .
    ,    
 ,       ,    
  .

  -------------------------------------------------------------------
  Linux  | TAPR TNC | Description
  -------------------------------------------------------------------
  T1     | FRACK    | How long to wait before retransmitting an
         |          | unacknowledged frame.
  -------------------------------------------------------------------
  T2     | RESPTIME | The minimum amount of time to wait for another
         |          | frame to be received before transmitting
         |          | an acknowledgement.
  -------------------------------------------------------------------
  T3     | CHECK    | The period of time we wait between sending
         |          | a check that the link is still active.
  -------------------------------------------------------------------
  N2     | RETRY    | How many times to retransmit a frame before
         |          | assuming the connection has failed.
  -------------------------------------------------------------------
  Idle   |          | The period of time a connection can be idle
         |          | before we close it down.
  -------------------------------------------------------------------
  Window | MAXFRAME | The maximum number of unacknowledged
         |          | transmitted frames.
  -------------------------------------------------------------------

5.2.       .

 2.1.*  2.0.* + moduleXX   ,  
        
 .   ,    
/proc/sys/net/.        , 
      . 
  /proc/sys/net/ax25/    
  AX.25.     .


   /proc/sys/net/ax25 / <portname> / :


  FileName              Meaning              Values                  
Default
  ip_default_mode       IP Default Mode      0=DG 1=VC               0
  ax25_default_mode     AX.25 Default Mode   0=Normal 1=Extended     0
  backoff_type          Backoff              0=Linear 1=Exponential  1
  connect_mode          Connected Mode       0=No 1=Yes              1
  standard_window_size  Standard Window      1  <= N <= 7            2
  extended_window_size  Extended Window      1  <= N <= 63           32
  t1_timeout            T1 Timeout           1s <= N <= 30s          10s
  t2_timeout            T2 Timeout           1s <= N <= 20s          3s
  t3_timeout            T3 Timeout           0s <= N <= 3600s        300s
  idle_timeout          Idle Timeout         0m <= N                 20m
  maximum_retry_count   N2                   1  <= N <= 31           10
  maximum_packet_length AX.25 Frame Length   1  <= N <= 512          256


  T1, T2  T3 -    ,     -
 . , ,  ,   
  sysctl   ,     
 10.       1/10 .
,    , eg T3  ,  
,   .

   /proc/sys/net/netrom/ :

  FileName                       Values                  Default
  default_path_quality                                   10
  link_fails_count                                       2
  network_ttl_initialiser                                16
  obsolescence_count_initialiser                         6
  routing_control                                        1
  transport_acknowledge_delay                            50
  transport_busy_delay                                   1800
  transport_maximum_tries                                3
  transport_requested_window_size                        4
  transport_timeout                                      1200

    /proc/sys/net/Rose/ :

  FileName                       Values                  Default
  acknowledge_hold_back_timeout                          50
  call_request_timeout                                   2000
  clear_request_timeout                                  1800
  link_fail_timeout                                      1200
  maximum_virtual_circuits                               50
  reset_request_timeout                                  1800
  restart_request_timeout                                1800
  routing_control                                        1
  window_size                                            3


,        -  
     . , 
    Rose,  :

       # cat /proc/sys/net/rose/window_size
       3
       # echo 4 >/proc/sys/net/rose/window_size
       # cat /proc/sys/net/rose/window_size
       4
