We are trying to add support to ethereal for data captured off a CDMA 1x data network. 

Most of the packets we capture contain PPP encapsulated in HDLC framing. Instead of 
the usual 0x880b identifier for PPP we get 0x8881. So far, we've modified ethereal to 
accept this value and strip off the HDLC framing and almost all of our packets are 
decoded correctly.

However, every so often we receive three packets in a row that look like the one 
below. The strange thing about this packet is that there is no HDLC framing, and the 
encapsulated IP packet seems to be truncated.

This is happening to about 20% of the packets that we are sniffing. We've tried it 
with several different sniffers (Network Associates Sniffer and Agilent Advisor) on a 
highly loaded network and on a test network with minimal load and get the same results.

Does anyone have any ideas on how (or if) we can decode the data? We're not sure if 
the data is some symptom of a problem on the network or just a symptom of how limited 
our knowledge of the protocol is.

Frame 765 (66 bytes on wire, 66 bytes captured)
Ethernet II, Src: 08:00:3e:03:02:01, Dst: 00:07:4f:87:90:1c
Internet Protocol, Src Addr: 10.160.31.69 (10.160.31.69), Dst Addr: 10.160.31.107 
(10.160.31.107)
Generic Routing Encapsulation
Point-to-Point Protocol
   Protocol: IP (0x0021)
Internet Protocol
   Version: 0
   Header length: 8 bytes (bogus, must be at least 20)

00 07 4f 87 90 1c 08 00 3e 03 02 01 08 00 45 00                     
00 30 1d 68 00 00 40 2f 09 48 0a a0 1f 45 0a a0
1f 6b 20 00 88 81 00 00 00 91

Encapsulated IP packet:

                              21 02 01 00 10 02 
06 00 2d 0f 00 03 06 0a a0 1f 63 64 08 7e fe 11
d3 01


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