Archive for March, 2010

Sa vad pe viu imbinarea celor 2 stiluri de muzica preferate ale mele: rock-ul si muzica simfonica.

Si…se va intampla, are loc pe 12 aprilie 2010, la Sala Palatului, Mozart Rocks, concert al Orchestrei Nationale Radio cu alti 8 chitaristi, interpretand compozitii din Bach, Beethoven, Schumann, Bizet, Brahms, Ceaikovsky.

Un sample (uvertura din Simfonia a 5-a – Beethoven) e aici:

http://www.mozartrocks.ro/

Acum e naspa cu finantele, dar sper sa mai gasesc bilete si dupa ce vine salariul pe aprilie. FINGERS CROSSSEEEDDD ๐Ÿ˜€ ๐Ÿ˜€ ๐Ÿ˜€

Mi-am luat bileeeeett !!! 100 RON, de la Germanos, zona A, randul 12, locul 14. Me Haappppyyy.

back to childhood

Posted: March 23, 2010 in media-culture
Tags: ,

Desene animate si anime deopotriva. Tom si Jerry si… mai nou am revenit la Bleach

Totul s-a intamplat astazi, cand am facut update la Firefox. M-a intrebat daca vreau personas si, ca sa vezi, al treilea theme din lista era Byakuya Kuchiki, conducatorul castei a 13-a, cea mai puternica, a Soul Society, un fel de Asgard in animele Bleach.

Imediat ce am ajuns acasa, am abuzat ftp-ul lui Ryan, ca sa mai iau episoade ๐Ÿ˜€ Now I’m again addicted.

Bleach__Memories_of_Nobody_by_skybl

 

bleach-wallpapers-3

So, in the previous post I have bluntly copy-pasted from the TS 23.401. Now, I have tried to also get a shiny capture of at least part of that conversation, more exactly, on the S11/S4 interface, the one between the MME and the SGW.

In the X2-based handover the MME never changes, it is the anchor point of the X2 handover. SGW may change or not, as per TS 23.401.

A. The scenario below depicts the case where the SGW does not change, in an X2 handover. The session creation and deletion are the same as before; what is different is the Modify Bearer Request and Modify Bearer Response messages.

55112

As you can see, the SGW does not change, it is the same, MME also does not change, only eNodeBs change. The UE travels from source eNB to target eNB. The X2-based handover assumes that there is an X2 link/interface between these 2 eNBs.

The message exchange is the following

1

— At first, the downlink and uplink data of this UE flows from the (only) SGW through the source eNB, then the UE.

At this point, the UE already has a number of bearers created, at least the default one, created using the initial Modify Bearer Request – Modify Bearer Response sequence:

Screen-shot-2010-03-22-at-6.57.42-PM

 

Screen-shot-2010-03-22-at-6.58.57-PM

 

* I have assumed here the 10.10.0.51 is the S11-MME IP of the MME entity, and the 10.10.0.101 is the S11-MME IP of the SGW.

* 10.10.0.1 is the GTP-c IP of the source eNB, and 10.10.0.2 is the GTP-c IP of the target eNB.

— While the UE moves towards the margin of the source eNB range, source eNB, target eNB and UE prepare the handover. At this point, the source eNB knows it can no longer contact the UE, therefore it forwards the dowlink data it receives from the SGW, to the target eNB, which, in turn, forwards the data to the UE. At this point, the UE already forwards the uplink data to the new eNB.

— What remains to be done is to tell the SGW that the user-plane path changed.ย This is triggered by the target eNB, via a Path Switch Request message sent to the (only) MME. The MME then sends a Modify Bearer Request message to the SGW. This message contains the F-TEID of the user-plane having as IP address the IP of the target eNB, instructing the SGW to forward all the data for this user/bearer to this eNB. The SGW forwards this message on S5/S8 to the PGW. If the confirmation is received with Request Accepted Cause, then the SGW forwards the reply to the MME. Immediately after this, any new downlink data is forwarded by the SGW to the target eNB.

Screen-shot-2010-03-22-at-6.59.29-PM

 

Screen-shot-2010-03-22-at-7.00.14-PM

* As you can see the TEIDs of the user-plane don’t change, only the F-TEID IP of the path.

* The outer TEIDs are also the same, all that changes is the F-TEID inside the Bearer Context. This handover should be seamless for the user-plane traffic, it’s TEID should not change and packets should not be lost on the way.

— The MME sends a Path Switch Request Ack to the target eNB to acknowledge the handover.

— The latest message comes from the target eNB to the source eNB, letting it know that it can release resources for that UE.

B. When doing X2-based handover with SGW relocation, the things are a bit more complicated, because a new session needs to be created between the (only) MME and the target SGW. This means the scenario would look like this:

55113

Here as well, the user-plane traffic would be forwarded from the source eNB to the target eNB temporarily, then, once the EPS signaling updates all the states on the target SGW, the downlink will also take place through the target SGW.

2

— Before starting the EPS signaling, the UE already forwards the uplink data to the target eNB, which then forwards it to the source SGW via the S1-U interface (as the target SGW is not yet in place).

— After the Patch Switch Request from the target eNB to the MME, the MME looks for an appropriate SGW to deal with the new target eNB user-plane path. The MME finds this to be the target SGW and initiates a Create Session Request to this new entity. If the target SGW replies, the session is created, allowing the downlink data from the PGW to be forwarded to the target eNB, via the target SGW.

— At this point, the MME send a Path Switch Request Ack to the target eNB, so that the uplink data from the UE can now be forwarded from the target eNB to the target SGW.

— In the end, the target eNB signals to the source eNB to release resources for this UE and the MME deletes the session with the source SGW.

As I was saying in a previous post, one of the handover types that can take place over LTE/SAE is the X2-based handover. This type of handover takes place when the UE moves from a cell controlled by one eNodeB (let’s call it source eNB) to a cell controlled by another eNB – target eNB. When this happens, the MME cannot be changed (basic condition of an X2-based handover). Still, the MME can decide whether or not to change the SGW. This means that there are 2 types of X2-based handover: with no SGW relocation and with SGW relocation. In both of them, the existence of the X2 interface between the source and target eNB is assumed.

As per TS 23.401, the behavior in case of X2 handover is the one below:[quoted from TS 23.401 – 5.5.1 Intra-E-UTRAN handover]

5.5.1.1 X2-based handover
5.5.1.1.1 General
These procedures are used to hand over a UE from a source eNodeB to a target eNodeB using the X2 reference point. In these procedures the MME is unchanged. Two procedures are defined depending on whether the Serving GW is unchanged or is relocated. In addition to the X2 reference point between the source and target eNodeB, the procedures rely on the presence of S1-MME reference point between the MME and the source eNodeB as well as between the MME and the target eNodeB.
The handover preparation and execution phases are performed as specified in TS 36.300 [5].
When the UE receives the handover command it will remove any EPS bearers for which it did not receive the corresponding EPS radio bearers in the target cell. As part of handover execution, downlink packets are forwarded from the source eNodeB to the target eNodeB. When the UE has arrived to the target eNodeB, downlink data forwarded from the source eNodeB can be sent to it. Uplink data from the UE can be delivered via the (source) Serving GW to the PDN GW. Only the handover completion phase is affected by a potential change of the Serving GW, the handover preparation and execution phases are identical.
If the MME receives a rejection to a NAS procedure (e.g. dedicated bearer establishment/modification/release; location reporting control; NAS message transfer; etc.) from the eNodeB with an indication that an X2 handover is in progress (see TS 36.300 [5]), the MME shall reattempt the same NAS procedure either when the handover is complete or the handover is deemed to have failed. The failure is known by expiry of the timer guarding the NAS procedure.
5.5.1.1.2 X2-based handover without Serving GW relocation
This procedure is used to hand over a UE from a source eNodeB to a target eNodeB using X2 when the MME is unchanged and decides that the Serving GW is also unchanged. The presence of IP connectivity between the Serving GW and the source eNodeB, as well as between the Serving GW and the target eNodeB is assumed.
1
NOTE 1: For a PMIP-based S5/S8, procedure steps (A) and (B) are defined in TS 23.402 [2].
1. The target eNodeB sends a Path Switch Request message to MME to inform that the UE has changed cell, including the TAI+ECGI of the target cell and the list of rejected EPS bearers. The MME determines that the Serving GW can continue to serve the UE
2. The MME sends a Modify Bearer Request (eNodeB address(es) and TEIDs for downlink user plane for the accepted EPS bearers) message to the Serving GW. If the PDN GW requested UE’s location info, the MME also includes the User Location Information IE in this message.
The MME releases the non-accepted bearers by triggering the bearer release procedure as specified in clause 5.4.4.2. If the Serving GW receives a DL packet for a non-accepted bearer, the Serving GW drops the DL packet and does not send a Downlink Data Notification to the MME.
3. If the Serving GW has received the User Location Information IE from the MME in step 2 the Serving GW informs the PDN GW(s) about this information that e.g. can be used for charging, by sending the message Modify Bearer Request (Serving GW Address and TEID, User Location Information IE) to the PDN GW(s) concerned. A Modify Bearer Response message is sent back to the Serving GW.
4. The Serving GW starts sending downlink packets to the target eNodeB using the newly received address and TEIDs. A Modify Bearer Response message is sent back to the MME.
5. In order to assist the reordering function in the target eNB, the Serving GW shall send one or more “end marker” packets on the old path immediately after switching the path as defined in TS 36.300 [5], clause 10.1.2.2.
6. The MME confirms the Path Switch Request message with the Path Switch Request Ack message. If the UE AMBR is changed, e.g. all the EPS bearers which are associated to the same APN are rejected in the target eNodeB, the MME shall provide the updated value of UE AMBR to the target eNodeB in the Path Switch Request Ack message.
If some EPS bearers have not been switched successfully in the core network, the MME shall indicate in the Path Switch Request Ack message which bearers failed to be established (see more detail in TS 36.413 [36]) and inititate the bearer release procedure as specified in clause 5.4.4.2 to release the core network resources of the failed EPS bearers. The target eNodeB shall delete the corresponding bearer contexts when it is informed that bearers have not been established in the core network.
7. By sending Release Resource the target eNodeB informs success of the handover to source eNodeB and triggers the release of resources. This step is specified in TS 36.300 [5].
8. The UE initiates a Tracking Area Update procedure when one of the conditions listed in clause “Triggers for tracking area update” applies.
NOTE 2: It is only a subset of the TA update procedure that is performed by the MME, since the UE is in ECM CONNECTED state and the MME is not changed.
5.5.1.1.3 X2-based handover with Serving GW relocation
This procedure is used to hand over a UE from a source eNodeB to a target eNodeB using X2 when the MME is unchanged and the MME decides that the Serving GW is to be relocated. The presence of IP connectivity between the source Serving GW and the source eNodeB, between the source Serving GW and the target eNodeB, and between the target Serving GW and target eNodeB is assumed. (If there is no IP connectivity between target eNodeB and source Serving GW, it is assumed that the S1-based handover procedure in clause 5.5.1.2 shall be used instead.)
2
Figure 5.5.1.1.3-1: X2-based handover with Serving GW relocation
NOTE 1: For a PMIP-based S5/S8, procedure steps (A) and (B) are defined in TS 23.402 [2].
1. The target eNodeB sends a Path Switch Request message to MME to inform that the UE has changed cell, including the ECGI of the target cell and the list of rejected EPS bearers. The MME determines that the Serving GW is relocated and selects a new Serving GW according to clause 4.3.8.2 on “Serving GW Selection Function”.
NOTE 2: The MME knows the S GW Service Area with a TA granularity.
2. The MME sends a Create Session Request (bearer context(s) with PDN GW addresses and TEIDs (for GTP-based S5/S8) or GRE keys (for PMIP-based S5/S8) at the PDN GW(s) for uplink traffic, eNodeB address(es) and TEIDs for downlink user plane for the accepted EPS bearers, the Protocol Type over S5/S8) message to the target Serving GW. The target Serving GW allocates the S GW addresses and TEIDs for the uplink traffic on S1_U reference point (one TEID per bearer). The Protocol Type over S5/S8 is provided to Serving GW which protocol should be used over S5/S8 interface. If the PDN GW requested UE’s location info, the MME also includes the User Location Information IE in this message.
The MME releases the non-accepted bearers by triggering the bearer release procedure as specified in clause 5.4.4.2. If the Serving GW receives a DL packet for a non-accepted bearer, the Serving GW drops the DL packet and does not send a Downlink Data Notification to the MME.
3. The target Serving GW assigns addresses and TEIDs (one per bearer) for downlink traffic from the PDN GW. The Serving GW allocates DL TEIDs on S5/S8 even for non-accepted bearers. It sends a Modify Bearer Request (Serving GW addresses for user plane and TEID(s)) message to the PDN GW(s). The S GW also includes User Location Information IE if it is present in step 2. The PDN GW updates its context field and returns a Modify Bearer Response (PDN GW address and TEID, Charging Id, MSISDN, etc.) message to the Serving GW. The MSISDN is included if the PDN GW has it stored in its UE context. The PDN GW starts sending downlink packets to the target GW using the newly received address and TEIDs. These downlink packets will use the new downlink path via the target Serving GW to the target eNodeB.
4. The target Serving GW sends a Create Session Response (Serving GW addresses and uplink TEID(s) for user plane) message back to the target MME. The MME starts a timer, to be used in step 7.
5. The MME confirms the Path Switch Request message with the Path Switch Request Ack (Serving GW addresses and uplink TEID(s) for user plane) message. If the UE AMBR is changed, e.g. all the EPS bearers which are associated to the same APN are rejected in the target eNodeB, the MME shall provide the updated value of UE AMBR to the target eNodeB in the Path Switch Request Ack message. The target eNodeB starts using the new Serving GW address(es) and TEID(s) for forwarding subsequent uplink packets.
If some EPS bearers have not been switched successfully in the core network, the MME shall indicate in the Path Switch Request Ack message which bearers failed to be established (see more detail in TS 36.413 [36]) and inititate the bearer release procedure as specified in clause 5.4.4.2 to release the core network resources of the failed EPS bearers. The target eNodeB shall delete the corresponding bearer contexts when it is informed that bearers have not been established in the core network.
6. By sending Release Resource the target eNodeB informs success of the handover to source eNodeB and triggers the release of resources. This step is specified in TS 36.300 [5].
7. When the timer has expired after step 4, the source MME releases the bearer(s) in the source Serving GW by sending a Delete Session Request message, which is acknowledged by the Serving GW.
8. The UE initiates a Tracking Area Update procedure when one of the conditions listed in clause “Triggers for tracking area update” applies.
NOTE 3: It is only a subset of the TA update procedure that is performed by the MME, since the UE is in ECM CONNECTED state. During the TA update procedure the MME deactivates ISR because of the S GW change.

Joan Shuterland

Ernani, 1979 – at least the part starting from minute 05:25

 

we haz rock-n-roll

Posted: March 11, 2010 in media-culture
Tags:

http://www.metalhead.ro/stiri/Concerte_Metallica_Rammstein_Slayer_Manowar_si_multi_altii_la_festi-aid-82368-l-1

Metallica

Megadeath

SLAYER

Rammstein

Alice in Chains…

and many more >:)

I haz bukz !!!

Posted: March 8, 2010 in personal
Tags:

Intotdeauna am cumparat carti misto pentru colegi si prieteni. Inca din liceu, erau cativa pasionati de Egiptul antic si alte mitologii, si le cumparam albume despre lucrurile alea, sau albume de arta. Eu ย nu am primit niciodata, in ciuda apropourilor evidente ca nu-mi plac bijuteriile si a bubelor pe care le faceam pe toata pielea in momentul cand, din politete, purtam pentru cateva ore bijuteriile primite.

Niciodata…pana ieri, cand monsieur mi-a facut cadou un roman super interesant (la modul ca am citit intr-o zi 270 de pagini, nu l-am putut lasa din mana), iar astazi colegii au plusat cu 2 albume mari despre DaVinci (unul cu picturi, iar altul cu schite), un album de Van Gogh, unul cu 100 de minuni ale lumii si unul despre Sky Scrapers.

How can I say this: ME HAPPY!!!!!

Ieri a fost ziua mea…dar ar fi fost prea banal. Asa ca (citate):

From: Cristina

Sent: 8 martie 2010 09:10
To: <all>
Subject: bomboane la bucatariile 6 si 9

Ma marit !

Aaa…pardon…ieri a fost ziua mea ๐Ÿ˜›

Iar Reply-urile:

Casa de piatra!
Pardon… La multi ani ๐Ÿ™‚

Casa de piatra! ย Aaa, scuze, la multi ani de 8 martie! ย Oh, la multi ani de ziua ta!!!! ๐Ÿ™‚

—dupa explicatia mea in scris ca e o gluma:

Pai e destul de explicitโ€ฆ te-ai maritat de ziua ta. Nu?…

:):):):):):)

Sa fie intr-un ceas bun! Casa de piatra! :):):):):):)

Aaaโ€ฆ pardon! La multi ani, multa sanatate in primul rand siโ€ฆ orice altceva iti doresti tu in al doilea ๐Ÿ™‚

Casa de piatra!
La Multi Ani!

Casa de piatra!La Multi Ani!

La multi ani!

Da esti sigura ca de fapt nu te-ai maritat ? ๐Ÿ™‚

————————–

Sent using BlackBerry

Casa de piatra si La multi ani! โ€“ ca sa fac coverage complet ๐Ÿ˜€

 

Ok, deci ieri a fost ziua ta si azi te mariti? ๐Ÿ˜€

La multi ani Cristina! Sa traiesti o viata frumoasa!

P.S. bomboanele de maritis/insuratoris se dau dupa eveniment, nu inainte ๐Ÿ˜›

Ce tareJ.

La multi ani din nou!

P.S.

Trebuia sa ziciย : Nascย ! ๐Ÿ˜›

Era sa-mi sara inimaโ€ฆ.

La multi ani !!!

 

—Ca sa fie clar pentru toata lumea: NU ma marit ๐Ÿ˜€ Not yet, at least 8-} ๐Ÿ˜›