RE: stds-802-16: forward request for help
See embedded comments.
Ken
-----Original Message-----
From: Roger B. Marks [mailto:r.b.marks@ieee.org]
Sent: Friday, December 12, 2003 7:30 AM
To: stds-802-16@ieee.org
Cc: wang.ning1@zte.com.cn
Subject: stds-802-16: forward request for help
I received some questions and, by permission of the submitter, am forwarding
them to the reflector for your consideration.
Regards,
Roger
>Roger Marks:
>
>hi,I have some questions about IEEE-802.16 and IEEE-802.16a Protocol,I
hoped to get your help.
>
>questions were depicted as below:
>
>1) whether management message service flow have their SFIDs when these CIDs
were allocated
<Ken S> The management connections are not considered services that would
need to be provisioned. As such they do not require SFIDs like services
associated with a service contract would.
>
>2) What the relationship between the priority of management message and
that of the Data such as UGS service if the management message with basic
CID has a higher priority than nrpts service flow?
<Ken S> The reason for dividing up the management into Basic, Primary, and
Secondary is that it was realized that there are really 3 classes of
management messages. The Basic Connection carries those that are short and
need a very fast response. Primary carries those that can be longer, but
don't need as quick a response time. The Secondary Management connection
carries standards based management traffic such as SNMP. Since the standard
does not specify scheduling algorithms, the means of handling these
management connections is left to the implementer. Generally, it would be
expected that the Basic connection would be treated as a real-time polling
connection. The Primary and Secondary Management connections would be more
likely to be treated as non-real-time polling services, but with different
traffic parameters.
>
>3) Since the Interval which was allocated for data transmiting can be
finished by UL-MAP How to allocate the bandwith for management messages such
as REG-REQ transmiting if the message such as DSx and SBC can be sent in
contention IE Initial ranging IE and Request IE
<Ken S> DSx and SBC messages, and all other management messages except for
RNG-REQ and bandwidth requests, cannot be sent in Initial ranging or request
IEs. They must be sent in Data IEs.
>
>4) In the P82 of the IEEE-802.16 there are depiction of "CRC shall be
calculated after encryption i.e. the CRC protects the Generic Header and the
ciphered Payload." but the figure 25 in P79 show that CRC appending begin
before MAC Header adding
>Whether the MAC Header should been considered in the CRC
<Ken S> You're right, these do contradict each other. I checked REVd/D1 of
the standard and the contradiction is still there. We need to correct this.
>
>5) whether the parameter of Initial ranging window is the same as that of
period ranging window
<Ken S> Unlike the Initial ranging window, periodic ranging is really any
opportunity to transmit data in the uplink. In the current version of the
standard, the station maintenance interval has been removed since it is more
efficient to just allocate a data grant to the terminal since the BS can
take necessary measurements off the data. So, periodic ranging
opportunities use the PHY mode currently being used for all uplink data by
the SS in question.
>
>6) Whether DSA message can add a active service flow directly when we want
to delete a service flow
>which step we should choose (a) we used DSD message to delete service flow
directly (b) we first used DSC to disactive the service flow then to delete
the admit service flow by DSD
<Ken S> Either is valid. Equipment receiving the DSx-REQ should be able to
handle either case. Equipment making the DSx-REQ can choose to do either.
>
>7) Which type of service flow can be disactive by DSC
>which type of service flow should be delete by DSD completely
>who are responsible for recreating the service flow been deleted SS or
network management system
<Ken S> This is a network management question that is outside the scope of
the standard. The answer depends upon whether you have a network with tight
provisioning of services. In this case, regardless of whether it's the SS
or BS that adds or deletes a connection, it should always be stimulated by
network management over the Secondary Management connection. In a less
managed system the SS and BS may bring up and tear down services as the need
arises. It really depends upon the service model of the network provider.
>
>8) For the OFDMA PHY layer because BS perform ranging by CDMA ranging code
BS don't kown the MAC address of SS when a SS power off how can BS recognize
certain SS's status and release its corresponding resource such as SFID
<Ken S> The CDMA ranging is an advantageous first step in OFDM systems. It
doesn't eliminate the need to send a REG-REQ after the SS gets the BS's
attention. Someone who's more OFDM knowledgeable than I can correct me if
I'm wrong.
>
>9) In the network of IEEE802.16 between the IP layer and CS sublayer
whether Ethernet sublayer can exist
<Ken S> Not certain I fully understand the question.
>
>10) There is a Downlink Channel ID in the DCD while it not involved in the
DL-MAP whether DL-MAP has the one to one correspondence relationship with
Downlink Channel ID
<Ken S> The Downlink Channel ID, is only used in the unlicensed bands. It
appears to me to simply be verification of which channel is being used. It
is not in the DL-MAP because there is only one DL-MAP each frame for the
channel.
>
>11) IEEE802.16a and IEEE802.16REVd have so many difference in OFDMA PHY I
think it difficult to make them compatible whether the IEEE802.16a will be
discarded in future
<Ken S> REVd replaces 802.16, 802.16a, and 802.16c. When REVd is approved,
802.16a will be obsolete.
>
>Best Regard,
>
>wangning
>
>wang.ning1@zte.com.cn