Here is an example of an IR packet that was exchanged at the ROHC
bakeoff at Roke Manor Research.

The input packet that went into this example is strange in that the P
bit is set -- ROHC compresses this fine, but an RTP implementation
would choke.

16:53:41.111211 172.16.100.1.53591 > 172.16.200.1.11831:  udp 28 [tos 0x8c] 
                         458c 0038 00ca 0000 b811 7d3b ac10 6401
                         ac10 c801 d157 2e37 0024 0000 a00d 6597
                         3788 7c22 5a70 4421 1011 1213 1415 1617
                         504b 543a 3030 3033

ROHC IR_hdr   : e8 fd 01 f3 40 11 ac 10 64 01 ac 10 c8 01 d1 57 2e 37 5a 70 
ROHC IR_hdr   : 44 21 8c b7 00 ca 20 00 00 00 b0 0d 65 97 37 88 7c 22 00 05 
ROHC IR_hdr   : 80 a0 

e8:	CID 8
fd:	IR, D=1 (dynamic chain present
01:	profile 0xnn01
f3:	CRC  (incorrect, unfortunately, should have been 53)
   static chain, IPv4:
40:	IPv4
11:	IP Protocol = 17 (UDP)
ac106401 (src address 172.16.100.1)
ac10c801 (dst address 172.16.200.1)
   static chain, UDP:
d157	 (source port)
2e37	 (dest port)
   static chain, RTP:
5a704421 (SSRC)
   dynamic chain, IP:
8c:	TOS
b7:	TTL
00ca	IP ID
20:	DF=0, RND=0, NBO=1
      generic extension header list
00:	ET=0, GP=0, PS=0, m=0
   dynamic chain, UDP:
0000	checksum
   dynamic chain, RTP:
b0:	v=2,p=1 (unusual!),rx=1,cc=0
0d:	m=0,pt=11
6597	SN
37887c22 TS
      generic CSRC list
00:	ET=0, GP=0, PS=0, m=0
05:	X=0, Mode=U, TIS=0, TSS=1
80a0	0b10=2 octets, Stride=160