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Re: [STDS-802-16] transport cid

Title:

Hi all,

I got good response for my question regarding transport CID and this is my understanding regarding the replies I got and some doubts,

 

  1. Transport CID is unique in both UL & DL for a connection. CID’s once assigned (in DL/UL) can’t be used again until it is de-allocated but this restriction doesn’t apply to transport CID. So this means that two different connections can have same transport CID?? (AS indicated by Mr. Phillip Barber reply “That reuse prohibition   includes for concurrent assignment in both the UL and DL. Note that the previous line   limits this restriction to transport connections”)
  2. From Mr.Peretz reply “CID is between the BS and MS (think of it as a MAC ID replacement), while SFID is between the BS and the NCMS. CID is directly mapped by the CS to an SFID”. So it means that SFID value won’t be provided to SS???
  3. Why SFID value is unique in UL & DL???

 

Plz excuse me for a lengthy mail, I want to make CID and SFID concept clear….

 

Thanks & reg

Vasanth

----- Original Message -----
Sent: Thursday, August 31, 2006 4:42 AM
Subject: Re: [STDS-802-16] transport cid

Peretz and all,
 
Just a clarification. Note the language in 802.16e-2005:
3.13 connection identifier (CID): A 16-bit value that identifies a transport connection or a uplink (UL)/downlink (DL) pair of associated management connections (i.e., belonging to the same subscriber station (SS)) to equivalent peers in the MAC of the base station (BS) and subscriber station (SS). The connection identifier (CID) address space is common (i.e., shared) between UL and DL and Table 345 specifies how it is partitioned among the different types of connections [emphasis added]. Security associations (SAs) also exist between keying material and CIDs. See also: connection.
This language is intended to clarify that, since CID number space is a common, managed pool for both UL and DL, once a number is allocated for assignment it cannot be used again until de-allocated. That reuse prohibition includes for concurrent assignment in both the UL and DL. Note that the previous line limits this restriction to transport connections.
 
Thanks,
Phillip Barber
Chief Scientist
Broadband Wireless Solutions
Huawei Technologies Co., LTD.
----- Original Message -----
Sent: Wednesday, August 30, 2006 5:31 PM
Subject: Re: [STDS-802-16] transport cid



On 8/30/2006 4:45 AM, Vasanth.Rajan wrote:

Hi all,

I have some doubt with transport CID and SFID, mentioned below

SFID for a specific connection (may be an Rtps connection) between BS and SS is unique in DL and UL;

SFID are directional in nature. Although possible, I wouldn't assume same SFID for both UL and DL but (as you indicated) unique per direction.

whether the same is true with Transport CID??? B’coz I was confused by the statement in a document as mentioned below,

“An SFID shall never be associated with more than one transport CID, and a transport CID shall

Never be associated with more than one SFID”

CID is between the BS and MS (think of it as a MAC ID replacement), while SFID is between the BS and the NCMS. CID is directly mapped by the CS to an SFID.

If it is different (both transport CID and SFID) then what significance it has???

After HO, SFID is the same but CID is different as a new mapping took place for the new serving BS.

Thanks

Vasanth