Survey

1
Survey

• S. J. Koh, et al., mSCTP for Soft Handover in
  Transport Layer, IEEE Comm. LETTERS, Vol. 8, No.
  3, Mar 2004 (Korea)
• I. Aydin, et al., Cellular SCTP A
  Transport-Layer Approach to Internet Mobility,
  IEEE ICCCN 2003 , 2003 (U of Delaware KISTI,
  USA Korea)
• Hung-Yun Hsieh, et al., An End-to-End Approach
  for Transparent Mobility across Heterogeneous
  Wireless Networks, Mobile Networks and
  Applications, No. 9, pp. 363378, 2004 (GIT, USA)
• A. Peddemors, et al., A Mechanism for Host
  Mobility Management supporting Application
  Awareness, ACM MobiSys04. (Netherlands)

2
mSCTP for Soft Handover in Transport Layer

• IEEE Comm. LETTERS, Mar 2004
• also in
• draft-sjkoh-mobile-sctp-mobileip-04.txt, (expired)

3
Introduction

• ADDIP extension for SCTP.
• It enables an SCTP endpoint to add a new IP
  address or delete an unnecessary IP address, and
  also to change the primary IP address used for
  the association, while an SCTP association is
  active.
• "Steam control tramission protocal (SCTP) dynamic
  address reconfiguration", draft-ietf-
  tsvwg-addip-sctp-09.txt. June 2004 (expired)

4
Step

1. Obtaining an IP address for a new location
2. Adding the new IP address to the SCTP association
3. Changing the primary IP address
4. Deleting the old IP address from the SCTP
   association

5
Issue

• The performance of mSCTP handover will depend on
  how to configure the triggering rules for adding
  a new IP address (Add-IP) and changing the
  primary IP address (Primary-Change) to an
  on-going SCTP association.

Q1 to mg How fast can MIP get a new CoA for
seamless handoff ? Solution or
Your idea ? Q2 to mg Your rules ?
6
Simulation
Under NS2
7
Rule for Add-IP

1. Aggressive Add-IP A new IP address is added to
   the association only if the associated wireless
   signal strength is greater than the Add-IP
   criteria (i.e., 3.6 X10 -10 ).
2. Conservative Add-IP A new IP address is added to
   the association if its wireless signal strength
   is greater than that those for the current IP
   addresses.

8
Rule for Primary-Change

• Aggressive (or higher) threshold for triggering
  Primary-Change 6.8 X 10 -10
• Conservative (or lower) threshold for triggering
  Primary-Change 4.7 X 10-10

9
Mobility Patterns
10
Result
11
Result (cont.)
12
Consulsion

• The mSCTP can be used to provide seamless
  handover for mobile sessions, without any support
  of network routers. The mSCTP performance seems
  to depend on the rules for triggering to add and
  change IP addresses to on-going associations
  during the handover.
• The aggressive Add-IP rules and the conservative
  Primary-Change rules are recommended for
  improving the mSCTP data transport efficiency.

13
Cellular SCTP A Transport-Layer Approach to
Internet Mobility
14
Idea

• Same idea with mSCTP, but CN duplicates and sends
  packets to both of the primary addresses to avoid
  slow start.
• Use SIP to get MNs new address.

15
Step

1. Detecting and obtaining a new IP address
2. Adding the new IP address into the association
3. Data Transfer During Handover (duplicate packet)
4. Deleting old IP address from the association

16
A Mechanism for Host Mobility Management
supporting Application Awareness
17
Architecture
18
Component

• Interface detection (ID)
• For supplying information about the creation and
  deletion of network interfaces in the OS
• Access Network Detection (AND)
• For supplying information about available
  networks for wlan interfaces by scanning at
  regular intervals.

19
Component (cont.)

• Access Network Selection (ANS)
• Get IP address from MIP
• Supply credentials for authentication and
  authorization.
• Indicates the preferred link layer connections

Again. Q3 to mg Your cost function for choosing
a good link.
20
Applications
21
An End-to-End Approach for Transparent Mobility
across Heterogeneous Wireless Networks
22

• I only look the drawback of mSCTP into this paper.

23
Problem of Mobile SCTP

• Mobile SCTP does not support in-sequence data
  delivery (across multiple streams) as TCP.
• Mobile SCTP does not allow multiple congestion
  control schemes to be used for different wireless
  interfaces.
• Mobile SCTP does not support bandwidth
  aggregation.

24
Reading List

• Congestion Control
• A. Gurtov and R. Ludwig ,Lifetime Packet Discard
  for Efficient Real-Time Transport over Cellular
  Links, ACM M2CR, Vol. 7, No. 4, 2003 (Finland
  Germany)
• Arch.
• P. D. Neumiller, et al., Open Base
  StationTransport (OBAST) Architecture, ACM MC2R,
  Vol. 4, No. 3, 2000 (Industry)
• Active Network in ..
• P. Patel, et al., Upgrading Transport Protocols
  using Untrusted Mobile Code, ACM SOSP 03. (U. of
  Utah and U. of Washington, USA , ANTS team)

25
IETF-draft Now

• Mobile SCTP draft-riegel-tuexen-mobile-sctp-04,
  Oct. 04
• Address Management for Mobile SCTP Handover
  draft-chang-mobile-sctp-address-mgt-01, Oct. 04
• SCTP Sockets API Extension for Congestion
  Handling draft-vibansal-sctpsocket-congestion-00,
  Dec. 04

26
IETF-draft Now (cont.)

• Sockets API Extensions for Stream Control
  Transmission Protocol (SCTP) draft-ietf-tsvwg-sct
  psocket-09, Sept. 04
• Error and Congestion Control Algorithm for mSCTP
  handover draft-chang-mobile-sctp-cc-00.txt ,
  Oct. 04