Extrémités A&B injoignables par LS

Bonjour,
je vous transmet ma demande d'aide pour diagnostiquer ce problème de connextion entre deux extremité par un liaison louée.
les deux extreminté n'arrive pas a communiquer entre eux.

voici une capture de texte d'hyperterminal effectuer dans deux temps different de moi de 10 secondes.

1er temps
Routeur>sh int s0
Serial0 is up, line protocol is up
Hardware is PowerQUICC Serial
Description: connected to Routeur-IAM
Internet address is 10.0.17.2/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:00:02, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/2/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
52918 packets input, 1270032 bytes, 0 no buffer
Received 52918 broadcasts, 0 runts, 0 giants, 0 throttles
17390 input errors, 0 CRC, 17388 frame, 0 overrun, 0 ignored, 2 abort
168305 packets output, 22021476 bytes, 0 underruns
0 output errors, 0 collisions, 35315 interface resets
0 output buffer failures, 0 output buffers swapped out
30 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up

2 temps
Routeur>sh int s0
Serial0 is up, line protocol is down
Hardware is PowerQUICC Serial
Description: connected to Routeur-
Internet address is 10.0.17.2/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 252/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:00:07, output 00:00:06, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/2/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
52925 packets input, 1270200 bytes, 0 no buffer
Received 52925 broadcasts, 0 runts, 0 giants, 0 throttles
17395 input errors, 0 CRC, 17393 frame, 0 overrun, 0 ignored, 2 abort
168340 packets output, 22024971 bytes, 0 underruns
0 output errors, 0 collisions, 35320 interface resets
0 output buffer failures, 0 output buffers swapped out
30 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up

entre temps dans la fenetre hyper terminal figure les linges suivantes :
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to down
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to down
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to down
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up
6d03h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to down

j'ai aussi pris une capture d'ecran montarant les requete de ping sur le routeur ( A) et (B) aisni que sur le serveur (B) mais je n'arrive pas a les joindre au forum

merci de venir a mon aide pour diagnostiquer ce problème

Config

Windows server 2003
Routeur Cisco 1700
Type de connexion Liason loué
Interface X.25