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Seeing 0xb8 instead of 2e for dscp value 46

0

Not sure why I would see Differentiated Services Field: 0xb8 I would expect to see Differentiated Services Field: 0x2e if my DSCP value is 46?

0100 .... = Version: 4
.... 0101 = Header Length: 20 bytes (5)
Differentiated Services Field: 0xb8 (DSCP: EF PHB, ECN: Not-ECT)
    1011 10.. = Differentiated Services Codepoint: Expedited Forwarding (46)
    .... ..00 = Explicit Congestion Notification: Not ECN-Capable Transport (0)

asked 21 Sep '16, 15:11

r1limited's gravatar image

r1limited
6223
accept rate: 0%


One Answer:

1

The Differentiated Services field is divided into two subfields: Differentiated Services Codepoint, which takes up 6 bits, and the Explicit Congestion Notification field, which takes the other two bits.

Yes, in your image, the Differentiated Services Codepoint is binary 101110, which is decimal 46, which would be hex 0x2e. However, the Differentiated Service Field is all 8 bits--the Differentiated Services Codepoint and the Explicit Congestion Notification field.

The whole thing is 1011 1000, which is decimal 184 and hex 0xb8.

answered 21 Sep '16, 15:39

Jim%20Aragon's gravatar image

Jim Aragon
7.2k733118
accept rate: 24%

Thank you so much for that explanation

(21 Sep '16, 15:41) r1limited