Hi Morne, thanks for the question.
There's no way to remark these to different DSCP values than the "two layer" approach (service > service-policy > service-class), unless all of your traffic is received uniformly... i.e., all HTTPS traffic is marked one way, all SIP traffic is marked another way, etc. The 128T's marking happens in one of two ways: either by applying a service-policy/service-class to a service, or by "falling through" to a session-type. It sounds like you're familiar with the former, but maybe the latter can help?
When you do NOT apply a service-policy/service-class to a service, then the 128T will look at the transport protocol and ports and try to classify that traffic as part of a session-type. E.g., UDP/5060 is SIP, TCP/443 is HTTPS, etc. (We have a bunch of these that come as part of your factory default configuration, but you can add any number of them on your own.) For each of these session-types, it'll also give you the opportunity to apply a service-class. Our built-in session-type for SIP uses the service-class "Signalling," which will cause SIP to get marked to DSCP 40.
If this is the case, you can use one service to forward all of the traffic with a handful of session-types and service-classes.
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pt.
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Original Message:
Sent: 04-11-2019 11:51
From: Morne Vermeulen
Subject: How services classes are mapped to a service
Hi All,
I have a question around how to simplify the attachment of service classes to services.
Myself and a colleague are currently building a network for an ISP, and our goal is to give them MPLS-like SLA and performance over multiple internet links.
Because this is an ISP and we will be transitting MPLS traffic, we will have to adhere to the QOS model that the ISP has implemented on their core network. We have configured 6 different service classes, which match what the ISP will be transitting. Then we created 6 different services for these classes to be mapped to. However, I see that service classes can only be applied to a specific service via a service policy.
Which means, in a deployment like this, we would have 6 service classes, 6 service policies and 6 services. But if I could map a service class directly to a service, this means I only need 6 service classes, 1 service policy, and 6 services. Is there an easier way of getting a service class mapped to a service, without the need of created extra service policies?
Regards,
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Morne Vermeulen
Engineer
+27 (0) 10 141 8512
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