Questions tagged [dscp]
For questions about DSCP in relation to Quality of Service (QoS). For instance, your switch does not tag your traffic into the correct DSCP value.
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Are all 64 DSCP values usable/configurable?
I have read that DSCP consists of 6 bits, thus providing us with 64 DSCP marking values (0-63).
If I understood all correctly, 21 of these values have been standardized and named (AF, EF, DF, etc)
...
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Classification and Marking using PCP
A networking course that I am following mentions that layer 2 marking can be performed through the use of PCP in the dot1q tag.
So to help me understand, once a switch receives a frame with a dot1q ...
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358
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Understand DSCP and Precedence Values in Ipv4 or Ipv6 packet
I read from this website to understand DSCP and it's corresponding IP precedence value.
For example DSCP value is '000 000' which Drop Probability is N/A(never happen) and it's Equivalent IP ...
- 356
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How to compare two DSCP ? which one of DSCP 28 and 34 (decimal) has more priority?
How to compare two DSCP ? for example which one of DSCP 28 and 34 (decimal) has more priority ?
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Why do we need machine learning for QoS classification in SDNs if we have DSCP in IP address for QoS enforcement?
DiffServ (Differentiated services) uses a 6-bit differentiated services code point (DSCP) in the 8-bit differentiated services field (DS field) in the IP header for packet classification purposes. If ...
- 103
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0
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431
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Prioritizing SSH, Telnet, TACACS in Cisco IOS
For Prioritizing SSH, Telnet, TACACS locally generated traffic on Cisco ASR running IOS XR, we have:
ssh server dscp 48
tacacs-server ipv4 dscp 48
Need the same for cisco GSR: 12416/PRP running IOS. ...
- 51
1
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1
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102
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Suggestion for Weights for Weighted Round Robin
I have looked over the book "End-to-End QoS Network Design" by Tim Szigeti et al. and RFC4594. The RFC proposes 14 Service class:
I have a switch with simple QoS features. It has 14 egress queues on ...
- 551
3
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1
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442
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STP packets and QoS
Routing protocol packets are IP packets and therfore they could have different DSCP values to have different priorities (which is implemented by QoS policy) during congestion.
How about non-IP packets?...
- 551
2
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1
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587
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QoS - Add DSCP EF tag with L2 switches?
Here is the topology that I have:
Phone => (access port) L2 Switch (trunk) => Router
My goal here is to add an EF tag to the packets coming from my phones. Basically, if a packet comes in being in ...
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QoS Classification and Drop Rate
Sorry if i sound completely senseless,
In CBWFQ,
q1) Does WRED only make sense if there is more than 1 dscp marking in a queue ?
q2) if traffic_typeA is to be handle with higher priority then ...
- 529
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0
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Changing DSCP values in a Cisco Switch [closed]
We have an endpoint which cannot tag outgoing RTP packets as 46 (EF)....
Currently they happily churn out as 0
Can the Cisco switch it is entering, recognise it's RTP traffic and then change the ...
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1
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Match cos is not supported for this interface in the output direction
I Have ROUTER CISCO ASR 903 ( IOS XE V3.18 )
ip access-list extended ip-google-traffic
permit ip 8.8.4.0 0.0.0.255 any
permit ip 8.8.8.0 0.0.0.255 any
permit ip 8.34.208.0 0.0.15.255 any
permit ...
- 331
1
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1
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What is Class-based WFQ and LLQ?
Can someone please explain those 2 concepts and rely them to marking, policing and shaping.
It is very confusing for me to rely these concepts with each other.
3
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1
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Are there any protocols that DSCP will break?
If you have a router that traffic passes through, and you want to classify different types of traffic using DSCP values, do you need to take special care to avoid setting DSCP values on certain types ...
- 155
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Fortigate - Routing DSCP tagged packets through different WAN connections
I have 3 WAN connections and a remote site with a single WAN address.
What I'd like to do is monitor the latency towards the remote site using a single machine (Opsview) on our LAN but through all 3 ...
- 113
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1
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772
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How packets get differentiated to prioritize?
On the Internet, there are many types of packets: VoIP, Audio, Video. As QoS is used to prioritize packets based on DSCP or VLAN priority. who set these bits for each and every packet. Like Audio gets ...
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1
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QOS on Nortel Devices
I need to set up the following on Several Nortel Baystack's (5530/5520):
"Assign a priority to DXL VoIP traffic with a DSCP priority level which will be co-exist with the rest of the real-time ...
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0
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DSCP to p bit mapping in Linux [closed]
Re posting from Unix forum as it may be appropriate for networking forum
I have the following setup
Linux1--------------------------------------------Linux2
eth0 10.10.10.30 ...
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3
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1
answer
821
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QoS DSCP AF Class Comparisons
I'm having trouble wrapping my head around DSCP AF Classes and what--all else being equal--gets dropped first.
I understand packets are given a Class, 1-4. The higher the Class number, the higher ...
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1
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Why doesn't ISPs reset DSCP at the edge before delivering traffic to customers?
Some ISPs are doing QoS based on traffic type (online streaming), such as Comcast and Cogent. Why don't they reset IP DSCP at the edge so it is not as obvious that they are doing some kind of traffic ...
- 1,281
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2
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How do I tag traffic with a DSCP value on an ASA?
I have a SIP Server that does not put a DSCP code on it's traffic. This server is behind an ASA, and I want to prioritize its traffic passing through an ASA from the private to public network.
I am ...
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DSCP trust boundary
I have performed some analysis and noticed that traffic coming in from the Internet contains a myriad of DSCP values. This traffic competes for voice and video resources on the internal network.
How ...
- 2,435
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QoS on HP Procurve 2520 and 3800 switches
Do Procurve switches remark cos/dscp values between switches (trust boundaries) as Cisco switches do?
I'm wondering if there is an equivalent to "mls qos trust (cos/dscp)" in the HP realm.
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