Собственно есть проблема собрать такую схему. Линк между киской и DSU есть, пинга нет... такая же ситуация с другой стороны (т.е. между HS и DSU). Вот часть конфига...  
Cisco
!
interface Ethernet0
ip address 212.23.76.41 255.255.255.240
no ip directed-broadcast
ip nat outside
no ip route-cache
no ip mroute-cache
!
interface Serial0
ip address 192.168.1.3 255.255.255.0
no ip directed-broadcast
ip nat inside
no ip route-cache
no ip mroute-cache
no keepalive
nrzi-encoding
!
ip nat pool 1 212.23.76.42 212.23.76.42 netmask 255.255.255.240
ip nat inside source list 1 pool 1
ip classless
no ip http server
!
access-list 1 permit 192.168.1.0 0.0.0.255
dialer-list 1 protocol ip permit
dialer-list 1 protocol ipx permit
!
___________________________________________
Serial0 is up, line protocol is up
  Hardware is HD64570
  Internet address is 192.168.1.3/24
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation HDLC, loopback not set
  Keepalive not set
  Last input never, output 00:00:43, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0 (size/max/drops); Total output drops: 0
  Queueing strategy: weighted fair
  Output queue: 3/1000/64/0 (size/max total/threshold/drops)
     Conversations  1/1/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 0 bytes, 0 no buffer
     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     2 packets output, 301 bytes, 0 underruns
     0 output errors, 0 collisions, 1 interface resets
     0 output buffer failures, 0 output buffers swapped out
     0 carrier transitions
     DCD=up  DSR=up  DTR=up  RTS=up  CTS=up
----------------------------------------------
Pipe (HS)
...
My Addr=192.168.1.1/24
...
Encaps=FR
...
Unit Type:    COE
State:         Up
Up Rate:  2320000
----------------------------------------------
Pipe (DSU)

+---------------------------------------------------------------+
|   Firmware Version: 4.2         Software Version: 3.31        
+---------------------------------------------------------------+
|   Bitpump Status:   OK          Terminal_Type:  RT            
|   Operation Status: UP          V.35  ON_Line                
|   Data Bit Polarity:Rev.        Sign/Magn Bit Seq:Rev.        
|   Noise Margin:  15.5 dB        Data Rate: 2320 kbps          
|   DSL ch Data Encode/Decode: NRZ                              
|   V35 ch Data Encode/Decode: NRZI                            
|   DSL ch Rx CRC: Disable        DSL ch Tx CRC: Disable        
|   V35 ch Rx CRC: Disable        V35 ch Tx CRC: Disable        
|   V35 ch RxC Polarity:Norm      V35 ch TxC Polarity:Norm      
+---------------------------------------------------------------+
|   Elapse Time:       0 day  0: 7:14                          
+---------------------------------------------------------------+

help... =(

• Cisco2514=={V.35}==DSU(SDSL)Pipe=={WAN}==DSL(HS)Pipe, A Clockwork Orange, 15:41 , 07-Сен-04, (1)  
  • Cisco2514=={V.35}==DSU(SDSL)Pipe=={WAN}==DSL(HS)Pipe, Senokos, 16:03 , 07-Сен-04, (3)  
• Cisco2514=={V.35}==DSU(SDSL)Pipe=={WAN}==DSL(HS)Pipe, sh_, 15:57 , 07-Сен-04, (2)  
  • Cisco2514=={V.35}==DSU(SDSL)Pipe=={WAN}==DSL(HS)Pipe, Demon_tm, 09:18 , 08-Сен-04, (4)