Wednesday, April 18, 2007

IMS Service Interaction Use Cases: Part 2

The last post presented 6 IMS service interaction use cases, which all had in common the fact that the initiator of the interaction was a client, typically a mobile handset or a PC soft client.

It is now time to consider service interactions initiated by an application server, as an IMS AS can support all the roles possible for a SIP entity, including the SIP User Agent (or client). This means that every SIP message generated or processed by an IMS client can also be generated or processed by an IMS application server. Consequently, you can take all the use cases described in the previous post, replace the client with an Application Server, and see if it makes sense. Alternatively you can keep on reading this post.

A preliminary question is: if a service on an application server can generate SIP messages, under which identity can it do it? There are two possibilities:
1) The service initiates the message under its own identity, which is a Public Service Identity (see previous post).
2) The service initiates the message under the identity of a user it serves, i.e. the service impersonates the user and acts on its behalf. This is acceptable because the application server is within the IMS security domain and under the control of the operator.

#7 John's service initiates interaction with John

The SIP message may be used to contact John himself or an application residing in a device associated to John. It may be targetted to any device or to a specific one. In this latter case, the service will use a Globally Routable User Agent URI (GRUU).

Service examples:
- Content push (SIP method can be MESSAGE, INVITE, REFER or PUBLISH)
- Deferred delivery of a stored message (SIP method can be MESSAGE or INVITE)
- Monitoring of user/application activity, e.g. is the user in a session? Is this application running? (SIP method is SUBSCRIBE)
- Access to local device information, e.g. what are the locally installed application? (SIP method is SUBSCRIBE)
- Initiation of stimulus based service control, i.e. user enters commands through typing on the keyboard or touching screen areas, the stimuli are translated into Keypad Processing Markup Language (KPML) and sent to the application for interpretation (SIP method is SUBSCRIBE, KPML semantic is tansported in NOTIFYs)

#8 John's service initiates interaction with Mary

This is basically the same as #7, except that the service is not associated to the user it interacts with and may even be from a different operator's domain. This is, a service offered by operator X can interact with a user or an application residing in a device of a user subscribed to operator Y.

For this kind of cross-user and potentially cross-domain service interaction, the service should act on behalf of the user it serves (John), so that identification and authorization can be performed adequately. Otherwise, the risk is that John's service, perceived as a total stranger from Mary's side, is authorized to very little if anything.

Service examples can be the same as for #7, except for deferred delivery messaging, which a priori makes sense only for an interaction between a service and the user it serves.

#9 John's service initiates interaction with another of John's services

Either acting with its own identity or on behalf of John, the service initiates a service interaction which is routed through the IMS service architecture to another application server hosting another of John's services.

This use case introduces the possibility for services associated to the same user to collaborate together using SIP, or to put it differently, for an IMS service to use another as an enabler. One can wonder why two IMS services would use SIP to interact when web services and SOA are just made for this. There can be several good reasons for this, including the fact that, as IMS applications, they naturally support SIP and they are just reusing an interface that has been defined for a client to application server usage. More especially, the enabling application will process a request from the requesting application just like it would process a request coming from an IMS client.

Service examples:
- John's session termination agent uses John's presence to decide how to process an incoming session attempt (SIP method is SUBSCRIBE)
- One of John's services issues a message to a group identifying a set of John's buddies. The second service is responsible for "exploding" the message distribution list to each of the intended users (SIP message is MESSAGE or INVITE)
- A service starts a conference call on behalf of John. The second service is the controller for the conference (SIP message is INVITE or REFER).
- One of John's services currently used by John automatically updates John's presence on his behalf (SIP method is PUBLISH)

#10 John's service initiates interaction with one of Mary's services

This use case is to #9 what #8 is to #7. John's service uses Mary's one as an enabler, and both can be located in different domains. Once again, John's service is likely to impersonate John in order for Mary's service to apply authorizations that are associated to John.

Service examples:
- An intelligent message routing service for John accesses Mary's presence to determine what is the best messaging mechanism to contact Mary (e.g. IMS messaging, SMS, MMS, email) right now or to send the message to all possible addresses associated to Mary (SIP method is SUBSCRIBE)
- A phone book service for John automatically retrieves all relevant contact information from Mary by quering her presence and/or other accessible information (SIP method is SUBSCRIBE)

Additional application server to application server use cases could be added, in which either the initiating or the recipient application server is located in the Internet. The use cases would be equivalent to those above, except that they could come with limitations essentially related to user authentication and end-to-end security (e.g. can the IMS application server trust the identity claimed by a request from the Internet?).

Believe or not, I am still not finished with IMS service interaction use case examples. The first 10 ones are simple peer-to-peer interaction use cases, using devices and application servers as peers. The next post will present use cases where application servers are inserted between peer-to-peer service interactions.

Christophe

10 comments:

Anonymous said...

fheidhmiocht http://cciworldwide.org/members/Furnace-Filters.aspx sitec http://cciworldwide.org/members/Vending-Machines.aspx cleanser http://cciworldwide.org/members/Kitchen-Cabinets.aspx shellfish http://cciworldwide.org/members/Slipcovers.aspx wehr http://cciworldwide.org/members/Polar-Heart-Rate-Monitors.aspx fern http://cciworldwide.org/members/Popcorn-Machines.aspx feast http://cciworldwide.org/members/Garage-Door-Openers.aspx gantries http://cciworldwide.org/members/Area-Rugs.aspx voyage http://cciworldwide.org/members/Omeprazole.aspx herold http://cciworldwide.org/members/Vacuum-Cleaners.aspx volatility http://cciworldwide.org/members/Annuity-Calculator.aspx jeffcoat http://cciworldwide.org/members/Bariatric-Surgery.aspx angelina http://cciworldwide.org/members/Electric-Blankets.aspx waives http://gotuc.net/members/Furnace-Filters/default.aspx enthusiast http://gotuc.net/members/Vending-Machines/default.aspx oppositions

Anonymous said...

Do You interesting of [b]Viagra 100mg dosage[/b]? You can find below...
[size=10]>>>[url=http://listita.info/go.php?sid=1][b]Viagra 100mg dosage[/b][/url]<<<[/size]

[URL=http://imgwebsearch.com/30269/link/buy%20viagra/1_valentine3.html][IMG]http://imgwebsearch.com/30269/img0/buy%20viagra/1_valentine3.png[/IMG][/URL]
[URL=http://imgwebsearch.com/30269/link/buy%20viagra/3_headsex1.html][IMG]http://imgwebsearch.com/30269/img0/buy%20viagra/3_headsex1.png[/IMG][/URL]
[b]Bonus Policy[/b]
Order 3 or more products and get free Regular Airmail shipping!
Free Regular Airmail shipping for orders starting with $200.00!

Free insurance (guaranteed reshipment if delivery failed) for orders starting with $300.00!
[b]Description[/b]

Generic Viagra (sildenafil citrate; brand names include: Aphrodil / Edegra / Erasmo / Penegra / Revatio / Supra / Zwagra) is an effective treatment for erectile dysfunction regardless of the cause or duration of the problem or the age of the patient.
Sildenafil Citrate is the active ingredient used to treat erectile dysfunction (impotence) in men. It can help men who have erectile dysfunction get and sustain an erection when they are sexually excited.
Generic Viagra is manufactured in accordance with World Health Organization standards and guidelines (WHO-GMP). Also you can find on our sites.
Generic Viagra is made with thorough reverse engineering for the sildenafil citrate molecule - a totally different process of making sildenafil and its reaction. That is why it takes effect in 15 minutes compared to other drugs which take 30-40 minutes to take effect.
[b][/b]
Even in the most sexually liberated and self-satisfied of nations, many people still yearn to burn more, to feel ready for bedding no matter what the clock says and to desire their partner of 23 years as much as they did when their love was brand new.
The market is saturated with books on how to revive a flagging libido or spice up monotonous sex, and sex therapists say “lack of desire” is one of the most common complaints they hear from patients, particularly women.

Anonymous said...

Hello,

I mostly visits this website[url=http://www.weightrapidloss.com/lose-10-pounds-in-2-weeks-quick-weight-loss-tips].[/url]theimslantern.blogspot.com is filled with quality info. Frankly speaking we really do not pay attention towards our health. In plain english I must warn you that, you are not serious about your health. Research shows that almost 50% of all United States grownups are either fat or overweight[url=http://www.weightrapidloss.com/lose-10-pounds-in-2-weeks-quick-weight-loss-tips].[/url] So if you're one of these individuals, you're not alone. Infact many among us need to lose 10 to 20 lbs once in a while to get sexy and perfect six pack abs. Now next question is how you can achive quick weight loss? Quick weight loss can be achived with little effort. If you improve some of your daily diet habbits then, its like piece of cake to quickly lose weight.

About me: I am blogger of [url=http://www.weightrapidloss.com/lose-10-pounds-in-2-weeks-quick-weight-loss-tips]Quick weight loss tips[/url]. I am also health trainer who can help you lose weight quickly. If you do not want to go under hard training program than you may also try [url=http://www.weightrapidloss.com/acai-berry-for-quick-weight-loss]Acai Berry[/url] or [url=http://www.weightrapidloss.com/colon-cleanse-for-weight-loss]Colon Cleansing[/url] for effective weight loss.

Anonymous said...

Howdy,

Do you guys watch movies in theater or on internet? I use to rent DVD movies from [b]Blockbuster.com[/b]. Recently I discovered that we can watch all new movies on internet on day, they are released. So why should I spend money on renting movies??? So, can you guys please tell me where I can [url=http://www.watchhotmoviesfree.com]watch latest movie Step Up 3D 2010[/url] for free?? I have searched [url=http://www.watchhotmoviesfree.com]Youtube.com[/url], [url=http://www.watchhotmoviesfree.com]Dailymotion.com[/url], [url=http://www.watchhotmoviesfree.com]Megavideo.com[/url] but, Could not find a good working link. If you know any working link please share it with me.


Thanks

Anonymous said...

[b]King Of Pirate Online[/b]

King Of Pirate is a fully 3D-designed multiplayer online game based on 5,000 years of pirate history.

In it, comical pirate characters and creatures travel the high seas and encounter intricate story-based quests,

wondrous cities and beautiful landscapes in their search for treasures fit for a king – or a king's ransom!

Though the excitement of ship-to-ship combat is a heady brew for newcomers and veterans alike,

many players take pride in their place among the community. Whether you seek to enforce the laws of the KoP world,

http://www.KingOfPirate.com





Tales of pirates private server
pirate king online private server
top/pko private server
private server
igg top
igg

Anonymous said...

Skilled brief, purchase generic cialis.
Generic Cialis is the stamp name of the hallucinogenic whose on the go ingredient is Tadalafil. Orally administered in the construct of tablets,
Base Tadalafil is hardened an eye to the treatment of erectile dysfunction (ED) in men.

Anonymous said...

http://tyrellrg.livejournal.com
http://ashwathkc.livejournal.com
http://caronro.livejournal.com
http://annabellkp.livejournal.com
http://lubomyslrk.livejournal.com
http://denacl.livejournal.com
http://jonahuv.livejournal.com
http://charoletteet.livejournal.com
http://luzym.livejournal.com
http://bernicegx.livejournal.com
http://haritoniyzm.livejournal.com
http://tyeshams.livejournal.com
http://lubomyslag.livejournal.com
http://derwinfr.livejournal.com
http://dannywq.livejournal.com
http://sharynoh.livejournal.com
http://judinays.livejournal.com
http://shonnadb.livejournal.com
http://pimenos.livejournal.com
http://agniyaoc.livejournal.com
http://rutesd.livejournal.com
http://katrinaus.livejournal.com
http://ayodejimk.livejournal.com
http://seannahu.livejournal.com
http://sabirecm.livejournal.com
http://stephsq.livejournal.com
http://paulinava.livejournal.com
http://mckittrickzl.livejournal.com
http://mercedesqp.livejournal.com
http://evyuo.livejournal.com
http://yolandavo.livejournal.com
http://algenismy.livejournal.com
http://burtjl.livejournal.com
http://koywl.livejournal.com
http://henessydx.livejournal.com
http://raynepm.livejournal.com
http://avinavoa.livejournal.com
http://zhozefinalf.livejournal.com
http://ladonnaab.livejournal.com
http://garviekk.livejournal.com

Anonymous said...

whats up everyone


just registered and put on my todo list


hopefully this is just what im looking for looks like i have a lot to read.

P.s I wanna have fun as well as learn

[url=http://www.blue-pencil.ca/]shredding services[/url]

Anonymous said...

hiya


just registered and put on my todo list


hopefully this is just what im looking for looks like i have a lot to read.

P.s I wanna have fun as well as learn

[url=http://www.blue-pencil.ca/]shred it[/url]

www.las-palmas-3d.com said...

It can't work in reality, that's exactly what I think.