Martin, Diego, Jim, Walter, and Jeffrey: Thank you for such a well-written document which provides a nice set of use cases. I have just a few editorial nits for you to consider fixing: Summary: This document is ready for publication, but it has a few nits (security question, and editorial points) that should be considered before publication. Security question: Section 7 points out that metadata contains sensitive information. I would suggest that you provide a short summary of threats that this metadata presents or point to a security document that provides these nits. As a reader, I would appreciate it if you did both. Editorial: 8 nits. Please resolve #5, #7 and #8 before publication. #1 Page 4 Old/: In many cases application- specific IP traffic is not directly exchanged between the original mobile network, more specifically the P-GW, and an application platform, but will be forced to pass a set of service functions. / New: /In many cases application-specific IP traffic is not directly exchange between the original mobile network (more specifically the P-GW), and an application platform, but will be forced to pass a set of service functions. / Why #1a: application- specific - needs to be changed to application-specific Why #1b: "mobile network, more specifically the P-GW," - did not flow as well as the use of (more specifically the P-GW)" - but this may just be a style moment. #2 Page 5, Section 1.2 NAPT - this abbreviation is not spelled out. It is customary to spell it out in the first use. #3 page 5, Section 1.3 FTTH - it would be useful to spell this out. #4) Page 11, section 2.4 In the sentences: Typical metadata and their sources are: UE: . GTP tunnel endpoint: . PCRF: . It would be good to use an indent for each of these key words. #5 p. 11, section 2.4 At the last paragraph, in the sentences that begins "The Traffic Steering Support Function (TSSF) has been defined recently (since Rel. 13)" It would be good to indicate which document's release 13 or if you intend a series of documents to explain this with a note. #6, section 3.1 paragraph 5, first sentence Old: /Last but not least the behavior/ New: /Last but not least, the behavior/ Why: Most common English usage places the idiom "last but not least" between commas if it is in the middle of a sentence. At the beginning of a sentence "Last but not least" has a comma immediately after. #7: section 3.1.1, paragraph 1, sentence 3 Old:/This classification could be done by the load balancer (see Figure 6), possibility directed by a TSFF (not shown), if it initiates the service change selection, or if the traffic can be reclassified at the load balancer if the traffic is already embedded in a Service Chain (e.g. when combined with other functions such as the TCP optimization in the following use case)./ New: (suggestion):/ This traffic classification could be done by: . the load balancer (see figure 6), . possibility directed by the TSFF (not shown in figure 6) - if it initiates the service change selection, . load balancer as part of a reclassification- if the traffic is already embedded in a Service chain (e.g. when combined with other functions such as the TCP optimization in the following use case. / Why: Most of your sentences are easy to read and clear, but this sentence was hard to read and unclear. Perhaps you could retain most of the original text with this simple formatting changes. The technical points in the sentence are very valuable. #8 - Section 4, paragraph 1, sentence 3 In sentence 2 and 3, you use Diameter based Gx or Sd reference point. You do not introduce St in [TS.23.203] as abbreviation or reference point. Please clarify this point. Sue Hares shares@ndzh.com