IETF Last Call Review of draft-ietf-dmm-tn-aware-mobility-25
review-ietf-dmm-tn-aware-mobility-25-genart-lc-dunbar-2026-05-12-00

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Review Team (Gen-ART) reviews all IETF documents being processed
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like any other last call comments.

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Document: draft-ietf-dmm-tn-aware-mobility-25
Reviewer: Linda Dunbar
Review Date: 2026-05-12
IETF LC End Date: 2026-05-13
IESG Telechat date: Not scheduled for a telechat

Summary: This document describes a way to map 5G user-plane traffic for a given
3GPP slice to the appropriate transport-network slice by using the GTP-U outer
UDP source port, including across mobility and handover.

Major issues: None

Minor issues: None

Nits/editorial comments:
- In the Introduction, “F-U” appears to be used where “F1-U” is probably
intended. - In Section 1, “UDP source port ranges in TN underlays for slice
mapping is described in Section 4” should be “are described in Section 4”. -
There are a few places where “to setup” should be “to set up,” for example in
Section 2 and Section 3.3. - In Section 3.2, “maybe realized in an NSS” should
be “may be realized in an NSS.” - The text says the solution does not depend on
VLANs, but Figure 3 includes VLAN matching prominently. A short note in the
figure caption or text saying VLAN is only illustrative would improve clarity.

Best Regards,

Linda Dunbar