Subject: Re: [ppsp] WG Action: Peer-to-Peer Streaming Protocol (PPSP)

From: Ning Zong <[email-masked]>
Date: Tue, 23 Mar 2010 20:33:25 -0800

Congratulations to all the people having been contributing to PPSP since the very begining. Let's continue to work together as before and make PPSP a successful WG.

BR,
Ning Zong

Great news!
I appreciate all of the contributions and sincere help from you,PPSP guys in making PPSP a WG after almost one and a half year's hardworking.
Thanks Lars,Gonzalo,Cullen and all those who give us good suggestions in boosting the PPSP progress.
Thanks IESG for the review and approval of PPSP charter.
Looking forward to making PPSP a successful protocol and practice under all of your hardworking.

BR
Yunfei

zhangyunfei
2010-03-24

发件人： IESG Secretary
发送时间： 2010-03-24 08:09:02
收件人： IETF Announcement list
抄送： [email-masked]; [email-masked]; [email-masked]
主题： WG Action: Peer-to-Peer Streaming Protocol (PPSP)

A  new  IETF  working  group  has  been  formed  in  the  Transport  Area.    For
additional  information,  please  contact  the  Area  Directors  or  the  WG
Chairs.

Peer-to-Peer  Streaming  Protocol  (PPSP)
--------------------------------------------------

Chair(s):
Yunfei  Zhang   <[email-masked] >
Cullen  Jennings   <[email-masked] >

Transport  Area  Director(s):
Magnus  Westerlund   <[email-masked] >
Lars  Eggert   <[email-masked] >

Transport  Area  Advisor:
Lars  Eggert   <[email-masked] >

Mailing  Lists:
Address: [email-masked]
To  Subscribe: https://www.ietf.org/mailman/listinfo/ppsp
Archive: http://www.ietf.org/mail-archive/web/ppsp/

Description  of  Working  Group:

The  Peer-to-Peer  Streaming  Protocol  (PPSP)  working  group  develops  two
signaling  and  control  protocols  for  a  peer-to-peer  (P2P)  streaming
system  for  transmitting  live  and  time-shifted  media  content  with  near
real-time  delivery  requirements.

Two  kinds  of  nodes  exist  in  the  targeted  P2P  streaming  system,  i.e.,
"peers"  and  "trackers".  Peers  are  nodes  that  are  actively  sending  and
receiving  streamed  media  content,  and  include  both  statically  connected
hosts  as  well  as  mobile  devices  with  connectivity  and  IP  addresses  that
change  over  time.  The  set  of  peers  that  are  participating  in  a  streaming
session  will  dynamically  change  over  time.  Trackers  are  well-known  nodes
with  stable  connectivity  that  maintain  meta  information  about  the
streamed  content  and  the  dynamic  peer  set.  Trackers  can  be  organized  in
centralized  or  distributed  ways.

The  PPSP  WG  designs  a  protocol  for  signaling  and  control  between
trackers  and  peers  (the  PPSP  "tracker  protocol")  and  a  signaling  and
control  protocol  for  communication  among  the  peers  (the  PPSP  "peer
protocol").  The  two  protocols  enable  peers  to  receive  streaming  data
within  the  time  constraints  required  by  specific  content  items.  The
tracker  protocol  handles  the  initial  and  periodic  exchange  of  meta
information  between  trackers  and  peers,  such  as  peer  lists  and  content
information.  The  peer  protocol  controls  the  advertising  and  exchange  of
media  data  availability  between  the  peers.

It  is  envisioned  that  the  tracker  protocol  will  be  modeled  as  a
request/response  protocol  between  peers  and  trackers,  and  will  carry
information  needed  for  the  selection  of  peers  suitable  for  real-time
streaming.  The  peer  protocol  is  envisioned  to  be  modeled  as  a
gossip-like  protocol  with  periodic,  pairwise  exchanges  of  neighbor  and
media  chunk  availability  information.  Both  protocols  will  be  carried
over  TCP  (or  UDP,  when  delivery  requirements  cannot  be  met  by  TCP),
likely  in  combination  with  ICE  for  NAT  traversal  support.  Perfect
privacy  protection  is  a  good  feature  to  have  but  not  a  mandatory
requirement  for  the  peer  and  tracker  protocols.  The  WG  will  consider  to
use  existing  protocols  as  design  base  for  the  tracker  and  peer
protocols.

Developing  mechanisms  for  searching  trackers  that  contain  a  specific
media  item  is  out  of  the  scope  of  this  WG.  Additionally,  the  WG  will
work  under  the  assumption  that  trackers  are  logically  centralized
entities  (e.g.,  a  single  server  or  a  server  farm  performing  DNS-based
local  balancing).  However,  as  far  as  it  is  possible,  the  WG  will  not
make  design  decisions  that  could  preclude  the  use  of  distributed
trackers  in  the  future  (e.g.,  DHT-based  trackers).

A  peer  looking  for  a  media  chunk  uses  the  tracker  and  peer  protocols  to
locate  a  remote  peer  (or  peers)  that  can  provide  it  with  that  media
chunk.  Obtaining  the  media  chunk  from  the  remote  peer  will  involve  some
type  of  signaling  exchange  plus  the  actual  media  transfer.  The  first
task  for  this  WG  will  be  to  decide  which  signaling  and  media  transfer
protocols  will  be  used.  The  WG  will  consider  existing  protocols  and,  if
needed,  identify  potential  extensions  to  these  protocols.  The  WG  will
consider  the  interactions  between  these  protocols  and  the  peer  protocol
(e.g.,  avoiding  duplicate  NAT  traversal  procedures).  Examples  of
signaling  protocols  to  be  considered  are  SIP,  RTSP,  and  HTTP.  Examples
of  media  transfer  protocols  to  be  considered  are  RTP  and  HTTP.

PPSP  is  not  chartered  to  work  on  media  transmission  protocols,  media
encoding  techniques  or  other  components  of  a  P2P  streaming  system  such
as  playout,  scheduling  and  control,  etc.

The  work  items  of  the  PPSP  WG  are:

(1)  A  "problem  statement"  document  that  gives  an  overview  of  the
proposed  P2P  streaming  system,  motivates  the  desire  for
standardized  protocols,  defines  the  envisioned  scope  of  those
standardized  components  and  discusses  common  terminologies  and
concepts.

(2)  A  "requirements"  document  that  details  the  specific  functional,
operational  and  performance  requirements  of  the  two  PPSP
protocols.

(3)  An  "architectural  survey"  document  that  summarizes  current  P2P
streaming  architectures,  in  particular  tracker-based  P2P
streaming  systems,  and  highlights  best  current  practices.

(4)  A  detailed  specification  of  the  PPSP  peer  protocol.

(5)  A  detailed  specification  of  the  PPSP  tracker  protocol.

(6)  A  "usage  guide"  that  describes  how  the  two  PPSP  protocols  and
existing  IETF  protocols,  such  as  P2PSIP  or  ALTO,  can  be  combined
to  create  a  deployable  operational  P2P  streaming  system.  This
document  may  also  discuss  variants  of  such  a  system  that,  for
example,  use  layered  media  encoding  and  related  media  chunk
descriptions  in  the  peer  protocol  for  more  robust  streaming.

The  work  items  of  the  PPSP  WG  interacts  with  the  work  performed  in  other
IETF  WGs,  including  P2PSIP,  SIPCORE,  AVT,  ALTO,  LEDBAT  and  MMUSIC.
Whenever  extensions  or  modification  to  the  protocols  developed  in  other
WGs  are  deemed  necessary,  PPSP  shall  communicate  and  discuss  the
requirements  for  such  extensions  with  the  relevant  WGs.  PPSP  is  not
chartered  to  design  and  specify  such  changes.

Goals  and  Milestones:

Dec  2010  Submit  problem  statement  to  IESG  as  Informational
Apr  2011  Submit  architectural  survey  to  IESG  as  Informational
Apr  2011  Submit  requirements  document  to  IESG  as  Informational
Aug  2011  Submit  PPSP  peer  protocol  to  IESG  as  Proposed  Standard
Aug  2011  Submit  PPSP  tracker  protocol  to  IESG  as  Proposed  Standard
Dec  2011  Submit  usage  guide  to  IESG  to  IESG  as  Informational

---

From: Ning Zong <[email-masked]>
Date: Tue, 23 Mar 2010 20:47:43 -0800

BR,
Ning Zong

Great news!

BR
Yunfei

zhangyunfei
2010-03-24

发件人： IESG Secretary

Chair(s):

Transport  Area  Advisor:

Mailing  Lists:
Address: [email-masked]

Goals  and  Milestones: