[rohc] Doubt regarding the Static chain termination for Profile 0x004

Ganesh <ganeshbabukamma@gmail.com> Fri, 12 February 2010 06:04 UTC

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From: Ganesh <ganeshbabukamma@gmail.com>
Date: Fri, 12 Feb 2010 15:05:36 +0900
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Subject: [rohc] Doubt regarding the Static chain termination for Profile 0x004
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Hi All,
I have one doubt regarding the Static chain termination part for Profile No
0x004,
as per the RFC 3843

*3.1. Static Chain Termination RFC 3843*
*
compressor can choose to end the static chain at any IP header, and indicate
this by setting the MSB of the IP version field to 1 (0xC for IPv4 or 0xE
for IPv6).

as per my Understanding
1. For IPV4,
+---+---+---+---+---+---+---+---+
 LSB             | MSB
+---+---+---+---+---+---+---+---+
| Version = 4 | 0          |
+---+---+---+---+---+---+---+---+

the MSB 0 has to be replaced By 1, so it will be as below (0xC for IPv4)
+---+---+---+---+---+---+---+---+
 LSB             | MSB
+---+---+---+---+---+---+---+---+
| Version = 4 | 1          |
+---+---+---+---+---+---+---+---+

2. For IPV6.  ( 0xE for IPv6)
+---+---+---+---+---+---+---+---+
 LSB             | MSB
+---+---+---+---+---+---+---+---+
| Version = 6 | Flow Label(msb)  |
+---+---+---+---+---+---+---+---+

RFC 3843 Mentions that MSB has to be replaced by 1, how can the 4 bits of
the flow Label MSB can be changed to 1??
is my understanding correct??
can anyone clarify my doubt??





*Thanks & Regards,
Ganesh Babu Kamma