[c-nsp] IP packet out of order.

[Olivier Gosselet]

Hi all,

I have the following setup :

Router A - Ethernet LAN - Bridge Eth/ATM - ATM Network - Router B - Ethernet
LAN

IP packet 1 - 1400 Bytes
IP packet 2 - 38 bytes

All routers ethernet interfaces are FIFO ... 

Packets are sent out by router A to router B in the following order : 1 - 2
Packets are sent out by router B onto the LAN in the following order : 2 - 1

According to my understanding of "IP over ATM" IP Packet are chopped into
ATM cells with IP Packet 1 contained into several ATM cells while IP Packet
2 fits into 1 cell. 
I know there is only one physical path in the ATM network from the bridge to
the router. I have no control on the ATM Bridge and/or Network but I would
assume they send and transport the resulting cells on a FIFO basis meaning
all the cell of packet 1 followed by the cell of packet 2. 
Would there be any chances that the Router B dequeues the second packet
first while the ATM cells were all received in the correct order.

Router 2 is a cisco 7206VXR (NPE400) 

Slot 2:
        ATM WAN OC3 (MM) Port adapter, 1 port
        Port adapter is analyzed
        Port adapter insertion time 1w0d ago
        EEPROM contents at hardware discovery:
        Hardware revision 2.0           Board revision A0

        Serial number     20666702      Part number    73-2430-04
        FRU Part Number:  PA-A3-OC3MM=

interface ATM2/0
 description To ATM switch
 no ip address
 load-interval 30
 no atm ilmi-keepalive

interface ATM2/0.x point-to-point
 description Cisco A to Cisco B
 ip address x.y.240.73 255.255.255.252
 ip mtu 1500
 ip ospf network broadcast
 atm route-bridged ip
 pvc Cisco A 12/800
  vbr-nrt 8000 8000
  encapsulation aal5snap

Your idea on this one would be highly appreciated.

Regards,

Olivier