Hi Peng, Please see my answer inline. Thanks, Sabine
-----Message d'origine----- De : He, Peng [mailto:[email protected]] Envoyé : lundi 4 novembre 2013 02:25 À : RANDRIAMASY, SABINE (SABINE); Qin Wu; IETF ALTO Objet : RE: I-D Action: draft-wu-alto-te-metrics-00.txt Hi Sabine, Sorry for the late response. Yes, I like this 'schedule' mode concept in your draft. Also agreed that might need to add this into the draft of -te-metrics, or a separate one. [ ] There seems to be an agreement on keeping the 'schedule' in a separate draft. Is it possible to consider the 'numerical' mode as a special case of 'schedule' mode, i.e., a constant value for all the time period, or it would be better to have both 'numerical' and 'schedule' modes separately? [ ] In a sense, 'numerical' and any other applicable mode are particular cases of schedule, with one single metric value provided. But I think it is simpler to provide the value as it is done in the base protocol and add just one "cost scope" attribute equal to "permanent". Otherwise we would need to define corresponding "cost scope" attributes (unit, size etc...) and carry them in the ALTO response, giving useless additional work to the ALTO Client. The draft provides an example in section 3.3 where the two modes 'numerical' and 'schedule' co-exist in the IRD. That is, for metric 'routingcost' the ALTO Server can provide a single 'synthetic' value as well as its detail in the 'schedule' mode. Of course, the draft needs further work to specify how the IRD indicates the "basic" type of JSONValue used for metrics provided in the schedule mode (e.g. 'numerical', 'string' ...). Likewise, any suggestion that may clarify the cost schedule terminology is welcome. Regards, Sabine Regards, Peng -----Original Message----- From: RANDRIAMASY, SABINE (SABINE) [mailto:[email protected]] Sent: Monday, October 28, 2013 7:54 AM To: He, Peng; Qin Wu; IETF ALTO Subject: RE: I-D Action: draft-wu-alto-te-metrics-00.txt -----Message d'origine----- De : [email protected] [mailto:[email protected]] De la part de He, Peng Envoyé : mercredi 23 octobre 2013 15:09 À : Qin Wu; IETF ALTO Objet : Re: [alto] I-D Action: draft-wu-alto-te-metrics-00.txt [ ] Hi Peng, Please see below and let me know if this would meet your request, Best regards Sabine Another side question: is there a 'cost' parameter that can show/represent the 'schedule' of the network links, e.g., before 12pm this link/tunnel will have say 100Mbps available, after 12pm, only 50mbps available, i.e., bandwidth scheduling or similar? Or this is more a management system/controller/server related data? [ ] There is a protocol extension proposal draft that proposes to provide cost values w.r.t. time and is called "ALTO Cost Schedule". ALTO Cost Schedule is specified as a cost mode where the ALTO Cost values are provided in the form of an array, where each array element corresponds to a given time period and has a value applicable to this period. The granularity of the time period, the number of provided values and other attributes are specified in the IRD. Note that the transaction format in this draft is compliant with the ALTO protocol version issued before the ALTO format changes in the Cost Type specification. In your example, the granularity may be 12 hours slots or say 1 hour slots to allow finer grain cost valuation. If we assume 1 hour slots and the availability of a metric called "availbw" expressed in mbps, where values can be provided both in regular 'numerical' mode with "permanent" validity and in 'schedule' mode: In the IRD we would have: (please forgive the possible mismatch of brackets) { ... usual ALTO resources ... "resources" : [ ....... { "uri" : "http://custom.alto.example.com/endpointcost/schedule/lookup";, "media-types" : [ "application/alto-endpointcost+json" ], "accepts" : [ "application/alto-endpointcostparams+json" ], "capabilities" : { "cost-constraints" : true, "cost-modes" : [ "numerical", "schedule" ], "cost-types" : [ "availbw", "availbw" ], "cost-scope": [ "permanent", {"unit": ["hour", 1], "size": 24, "begin": 0, "time zone": "UTC", "lastupdate": mm/hh/dd/mm/yyyy, "nextupdate": mm/hh/dd/mm/yyyy} ] } } ] } If the ALTO Servers provides availbw = 100mbps for the first 12 hours and 50mbps for the next 12 hours on the tunnel with example endpoints (192.0.2.2, 192.0.2.89), the ALTO request and response in schedule mode would look like: POST /endpointcost/lookup HTTP/1.1 Host: alto.example.com Content-Length: [TODO] Content-Type: application/alto-endpointcostparams+json Accept: application/alto-endpointcost+json,application/alto-error+json { "cost-type" : ["availbw"], "cost-mode" : ["schedule"], "endpoints" : { "srcs": [ "ipv4:192.0.2.2" ], "dsts": [ "ipv4:192.0.2.89", "ipv4:198.51.100.34", "ipv4:203.0.113.45" ] } } HTTP/1.1 200 OK Content-Length: [TODO] Content-Type: application/alto-endpointcost+json { "meta" : {}, "data" : { "cost-type" : ["availbw "], "cost-mode" : ["schedule"], "map" : { "ipv4:192.0.2.2": { "ipv4:192.0.2.89" : [100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 50 ... (12 same values)], "ipv4:198.51.100.34" : [... (24 values) ...], "ipv4:203.0.113.45" : [... (24 values) ...] } } } } The proposal is documented in http://tools.ietf.org/html/draft-randriamasy-alto-cost-schedule-02 where Section 3.3 provides an example on the Schedule attributes in the IRD, and section 3.3.1 provides example transactions with the Schedule mode. [ ] Regards, Peng -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Qin Wu Sent: Tuesday, October 22, 2013 9:17 PM To: IETF ALTO Subject: [alto] FW: I-D Action: draft-wu-alto-te-metrics-00.txt Hi, all: We have posted a new draft to define a set of new cost metrics that are related to traffic engineering performance information. http://tools.ietf.org/html/draft-wu-alto-te-metrics-00 Please review the draft and provide your feedback and comments. Regards! -Qin -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Monday, October 21, 2013 2:08 PM To: [email protected] Subject: I-D Action: draft-wu-alto-te-metrics-00.txt A New Internet-Draft is available from the on-line Internet-Drafts directories. Title : ALTO Traffic Engineering Cost Metrics Author(s) : Qin Wu Young Lee Dhruv Dhody Sabine Randriamasy Filename : draft-wu-alto-te-metrics-00.txt Pages : 26 Date : 2013-10-20 Abstract: Cost Metric is a basic concept in Application-Layer Traffic Optimization (ALTO). It is used in both the Cost Map Service and the Endpoint Cost Service. Future extensions to ALTO may also use Cost Metric. Different applications may benefit from different Cost Metrics. For example, a Resource Consumer may prefer Resource Providers that have low latency to the Resource Consumer. However the base ALTO protocol [ALTO] has defined only a single cost metric, i.e., the generic "routingcost" metric (Sec. 14.2 of ALTO base specification [ALTO]). In this document, we define XXX Cost Metrics, derived from OSPF-TE and ISIS-TE, to measure network delay, jitter, packet loss, hop count, and bandwidth. The metrics defined in this document provide a relatively comprehensive set of Cost Metrics for ALTO focusing on traffic engineering. Additional Cost Metrics such as financial cost metrics may be defined in other documents. The IETF datatracker status page for this draft is: https://datatracker.ietf.org/doc/draft-wu-alto-te-metrics There's also a htmlized version available at: http://tools.ietf.org/html/draft-wu-alto-te-metrics-00 Please note that it may take a couple of minutes from the time of submission until the htmlized version and diff are available at tools.ietf.org. Internet-Drafts are also available by anonymous FTP at: ftp://ftp.ietf.org/internet-drafts/ _______________________________________________ I-D-Announce mailing list [email protected] https://www.ietf.org/mailman/listinfo/i-d-announce Internet-Draft directories: http://www.ietf.org/shadow.html or ftp://ftp.ietf.org/ietf/1shadow-sites.txt _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto
