Questions[dscp](server)

I am trying to prioritize TCP traffic using ToS field in IP header. I am saturating the interface(ethernet) by sending 1GB data through iperf with ToS field set to 0x10 (Minimize-Delay). I then start another TCP client with default ToS (0).

Expectation : My TCP client should not send data till iperf completes sending its data.

Result: The data from my client is sent even tough iperf is sending packets with higher priority.

I also tried to create the same scenario by creating 2 separate clients and allocating 0x10 and 0x08 ToS to respective clients using iptables. I used : iptables -A PREROUTING -t mangle -p tcp --sport 5000 -j TOS --set-tos Minimize-Delay

I am still not able to prioritize one client over other.

I am using Ubuntu (14.04) with iptables version 1.4.21

Can someone kindly help me solve the issue?

Thanks Varun

I have to validate whether my router's QOS policies are working correctly.I have come up with an approach to tag the packets with DSCP values using IPTABLES.

Can anyone confirm whether my approach is correct?If not please provide your help to correct the same.

IPtables rule

# Mark packets based on the originating port and other requirements mentioned in the table

iptables -t mangle -A OUTPUT -p IGMP -m udp --sport 5051 -j DSCP --set-dscp-class cs5 iptables -t mangle -A OUTPUT -p IGMP -m IGMP --sport 5052 -j DSCP --set-dscp-class cs5 iptables -t mangle -A OUTPUT -p udp -m udp --sport 5053 -j DSCP --set-dscp-class cs5 iptables -t mangle -A OUTPUT -p udp -m udp -d xxx.123.219.132/32 --dport 5054 -j DSCP --set-dscp-class cs2 iptables -t mangle -A OUTPUT -p udp -m udp -d xxx.123.219.132/32 --dport 5055 -j DSCP --set-dscp-class cs2 iptables -t mangle -A OUTPUT -p udp -m udp --sport 5056 --dport 123 -j DSCP --set-dscp-class cs2 iptables -t mangle -A OUTPUT -p udp -m udp --sport 5057 --dport 67:68 -j DSCP --set-dscp-class cs2 iptables -t mangle -A OUTPUT -p udp -m udp --sport 5058 --dport 53 -j DSCP --set-dscp-class cs2

Setting 'policy based QoS' on Windows 10 does not apply the DSCP value to outgoing traffic. I want to be able to set the value of DSCP traffic for certain processes.

Using gpedit.msc group policy editor, I created a policy under Computer configuration > Windows Settings > Policy-based QoS > and set a DSCP value of '10'. I tried with or without an executable name. Whatever I do, looking at the traffic in NetMon shows a DSCP value of 0.

This worked under Windows 7 after applying the 'do not use NLA' registry key https://support.microsoft.com/en-gb/kb/2733528

However, even with this added, the DSCP is always 0.