Explains QoS marking modes for MPLS traffic, including uniform, pipe, and short-pipe behavior for preserving or changing QoS markings across MPLS networks.
QoS marking modes for MPLS traffic is a QoS traffic differentiation feature for MPLS traffic that
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determines how the network preserves or rewrites packet priority markings as traffic moves between network domains
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applies to MPLS networks that carry IPv4 or IPv6 packets, defining how DSCP or Class of Service (CoS) values are mapped to or restored from MPLS Experimental (EXP) bits, and
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uses uniform mode to preserve ingress markings across domains and pipe mode to apply domain-specific QoS policies.
| Feature Name |
Release Information |
Feature Description |
|---|---|---|
| Packet Marking for IPv4 and IPv6 Traffic |
Release 25.4.1 |
Introduced in this release on: Fixed Systems (8700 [ASIC: K100], 8010 [ASIC: A100])(select variants only*) *This feature is supported on:
|
| Packet Marking for IPv4 and IPv6 Traffic |
Release 25.1.1 | Introduced in this release on: Fixed Systems (8010 [ASIC: A100])(select variants only*) *This feature is supported on Cisco 8011-4G24Y4H-I routers. |
| Packet Marking for IPv4 and IPv6 Traffic |
Release 24.4.1 | Introduced in this release on: Fixed Systems (8700) (select variants only*) You can use uniform or pipe modes to implement QoS for IPv4 and IPv6 traffic. *This functionality is now extended to the Cisco 8712-MOD-M routers. |
| Packet Marking for IPv4 and IPv6 Traffic |
Release 24.3.1 | Introduced in this release on: Modular Systems (8800 [LC ASIC: P100]) (select variants only*), Fixed Systems (8200) (select variants only*), Fixed Systems (8700 (P100, K100)) (select variants only*) You can use uniform or pipe modes to implement QoS for IPv4 and IPv6 traffic. *This feature is supported on:
|
| Packet Marking for IPv4 and IPv6 Traffic |
Release 24.2.11 | Introduced in this release on: Modular Systems (8800 [LC ASIC: P100])(select variants only*) Using uniform or pipe modes, you can implement QoS for IPv4 and IPv6 traffic. Uniform mode maintains DSCP marking for packets across different network segments and is useful where the network policy requires consistent treatment of packets across multiple domains. Pipe mode separates QoS policies between network segments. In this mode, ingress DSCP markings classify and queue the packets, but the packets can remarked before they egress. Such treatment is beneficial when you need to apply one set of QoS policies within your network and a different set when packets exit the network towards your customer. *This feature is supported on 88-LC1-36EH. |
MPLS QoS marking modes
You can apply QoS marking on IPv4 and IPv6 packets that traverse an MPLS network using uniform or pipe modes.
Uniform mode: It's a DiffServ-aware MPLS marking mode that preserves the incoming IP header’s DSCP or CoS values throughout the MPLS domain. When packets are label-imposed and later disposed, the same DSCP values are copied into and out of the MPLS EXP field. This approach ensures consistent, end-to-end QoS treatment across provider and customer networks, making it suitable where network domains share a common QoS policy.
Pipe mode: It's a DiffServ-aware MPLS marking mode that isolates QoS policies between domains. In this mode, the MPLS domain applies its own EXP-based treatment that may differ from the IP DSCP values received at ingress. The original IP markings are restored (or re-applied) when packets egress, enabling independent QoS control within the MPLS provider network.
This table shows the details for uniform and pipe modes.
| Uniform mode | Pipe mode |
|---|---|
| Preserves ingress DSCP or CoS markings across the MPLS domain. | Applies new MPLS EXP markings based on provider QoS policy. |
| Provides consistent end-to-end QoS treatment across interconnected network domains. | Enables independent QoS enforcement within the MPLS provider network. |
| DSCP values are copied into and out of MPLS EXP fields during label imposition and disposition. | DSCP values are used only at ingress for classification; packets may be remarked at egress. |
| Suitable when customer and provider networks share a common QoS model. | Suitable when customer and provider networks maintain distinct QoS models to enable policy separation and administrative autonomy. |