Lifehacking, Security, Skype for Business

QoS troubleshooting with Wireshark

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During my work i have a lot of VoIP traffic related queries/questions. I’m using this configuration to check if packets are being tagged with the right DSCP values.

Add DSCP column to your Wireshark Client

1. Right click on one of the existing columns.
2. Click on column preferences
3. Click Add down the bottom
4. Click on the “New Column” Label and change it to “DSCP” then hit enter once.
5. With the new entry highlighted, change the Field Type to Custom (in the dropdown box)
6. In field name, copy and paste in ip.dsfield.dscp
7. Click Apply/Ok

You can drag the column back to the left side of the Info column and you now have a simple view of the tag for any packet.

Filter

You can also set a filter to capture all packets with DSCP value 46

ip.dsfield.dscp == 46

Reference

Here’s a table of DSCP and TOS values in their most common formats just for reference.
TOS (Dec) TOS (Hex) TOS Precedence Name TOS Delay flag TOS Throughput flag TOS Reliability flag DSCP (Hex) DSCP (Dec) DSCP/PHB Class
0 0x00 Routine 0 0 0 0x00 0 none
4 0x04 Routine 0 0 1 0x01 1 none
8 0x08 Routine 0 1 0 0x02 2 none
12 0x0C Routine 0 1 1 0x03 3 none
16 0x10 Routine 1 0 0 0x04 4 none
32 0x20 Priority 0 0 0 0x08 8 cs1
40 0x28 Priority 0 1 0 0x0A 10 af11
48 0x30 Priority 1 0 0 0x0C 12 af12
56 0x38 Priority 1 1 0 0x0E 14 af13
64 0x40 Immediate 0 0 0 0x10 16 cs2
72 0x48 Immediate 0 1 0 0x12 18 af21
80 0x50 Immediate 1 0 0 0x14 20 af22
88 0x58 Immediate 1 1 0 0x16 22 af23
96 0x60 Flash 0 0 0 0x18 24 cs3
104 0x68 Flash 0 1 0 0x1A 26 af31
112 0x70 Flash 1 0 0 0x1C 28 af32
120 0x78 Flash 1 1 0 0x1E 30 af33
128 0x80 FlashOverride 0 0 0 0x20 32 cs4
136 0x88 FlashOverride 0 1 0 0x22 34 af41
144 0x90 FlashOverride 1 0 0 0x24 36 af42
152 0x98 FlashOverride 1 1 0 0x26 38 af43
160 0xA0 Critical 0 0 0 0x28 40 cs5
176 0xB0 Critical 1 0 0 0x2C 44 voice-admit
184 0xB8 Critical 1 1 0 0x2E 46 ef
192 0xC0 InterNetworkControl 0 0 0 0x30 48 cs6
224 0xE0 NetworkControl 0 0 0 0x38 56 cs7

Lifehacking

Challenge yourself to ‘Inbox Zero’

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Inbox Zero

Do you also recognize a overloading email inbox, to much unreaded emails and no time to clean up, ‘Inbox Zero’ may be the solution for your problem!

Yesterday i was reading a blog (sorry, it’s in Dutch) from Michel Bouman from Microsoft. Last year he wrote a blog about how he implemented ‘Inbox Zero’ method by Merlin Mann in his life. In short terms, you have 4 folders(categories):

  • Action
  • Archive
  • Sometime
  • Waiting For

Every email you receive you will validate agains the rules below:

– Delete or Archive emails with no action requirered.
– Reply emails with action request, only if possible in two minutes.
– Emails above two minutes move to Action folder.
– Emails with action who you can delegate, you’ll forward inmediately, add your email to BCC to track. (explaination setting this up later in this blog)
– Interesting emails without action, containing a lot of text you can move to the folder  ‘Sometime’. This kind of emails you read in the morning with your first coffee or at the end of the day.

Now that you have categorized your email you’ll have to block some time in your agenda to process the Action emails.

There are many thing that i want to improve in my life, efficiency is one of them (ongoing process)! I spend a lot of my time everyday with chasing, reading and answering emails (Work and Private), This blog was opening my eyes, it’s time to tackle this issue.

Let’s give it a try and Challenge yourself.

Starting the Challenge to ‘Inbox Zero’

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