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Point-to-Point IM Interworking session Between SIP and MFTS

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					                                                              (IJCSIS) International Journal of Computer Science and Information Security,
                                                                                                                        Vol. 8, No. 7, 2010

 Point-to-Point IM Interworking Session Between SIP
                      and MFTS
       1
           Mohammed Faiz Aboalmaaly, 2Omar Amer Abouabdalla 3Hala A. Albaroodi and 4Ahmed M. Manasrah
                                              National Advanced IPv6 Centre
                                                 Universiti Sains Malaysia
                                                    Penang, Malaysia
                     1
                       essa@nav6.usm.my, 2omar@nav6.usm.my, 3hala@nav6.usm.my, 4ahmad@nav6.usm.my


Abstract— This study introduces a new IM interworking                     clients. The MFTS has been adopted in the Multimedia
prototype between the Session Initiation Protocol (SIP) and the           Conferencing System (MCS) product [4] by the Document
Multipoint File Transfer System (MFTS). The interworking                  Conferencing unit (DC), which is a network component that is
system design is presented as well. The interworking system relies        responsible for any user communications related to file sharing
on adding a new network entity to enable the interworking which           as well as instant messaging interaction.
has the ability to work as a SIP server to the SIP-side of the
network and as a MFTS server to the MFTS-side of the network.
Use Cases tool is used to describe the translation server                    II.   SIP AND MFTS AS INSTANT MESSGING PROTOCOLS
architecture. Finally, experimental-based results show that the
interworking entity is able to run a successful point-to-point            A. MFTS as an Instant Messaging Protocol
interoperability IM session between SIP and MFTS that involved                As everyone knows, Instant Messaging is a type of near
user registration and message translations as well.                       real-time communication between two or more people based on
                                                                          typed text. The text is carried via devices connected over a
   Keywords- SIP; MFTS; Instant Messaging (IM);                           network such as the Internet. MFTS in turn, uses control
                                                                          messages as a carrier to send and receive instant messages
                       I.    INTRODUCTION                                 (with text) among MFTS clients. As a normal IM
    Over the last few years, the use of computer network                  communication, an MFTS client sends several instant messages
systems to provide communication facilities among people has              with a variety of lengths to one or more MFTS clients. Figure 1
increased; hence the service provided for this area must be               depicts the standard structure of the MFTS control message
enhanced. Various signaling protocols have arisen and many
multimedia conferencing systems have been developed that use
these signaling protocols in order to provide audio, video, data
and instant messaging communication among people.
Transparent interoperability between dissimilar signaling
protocols and Instant Messaging and Presence (IMP)
applications has become desirable in order to ensure full end-
to-end connectivity. In order to enable the interoperability
between two or more different signaling protocols or standards,
a translation mechanism must exist in between to translate the
non-similar control options and media profiles. SIP [1], is a                             Figure 1.   MFTS Message Structure
well-known signaling protocol that has been adopted in many
areas and applications in the Internet as a control protocol. SIP             As depicted above, the MFTS message is divided into five
is an application layer protocol, used for establishing,                  main fields Message Type, Command, Sender Information,
modifying and ending multimedia sessions in an IP-based                   Receiver(s) Information, and Parameters. Message type is used
network. SIP is a standard created by the Internet Engineering            to indicate the purpose of the message whether it is client to
Task Force (IETF) for initiating an interactive user session that         server message or it is a server to server message, while the
involves multimedia elements such as, video, voice, chat,                 command indicates the specific name of the message like
gaming and virtual reality. It is also, a request-response                Private Chat (PRCHAT), the Command is a six character
protocol; like the HTTP [2], it uses messages to manage the               length. Additionally, Sender info and receiver(s) are used to
multimedia conference over the Internet. On the other hand,               identify the IP address of both the sender and the receiver
The Multipoint File Transfer System or (MFTS) [3] is a file               respectively. Parameters are used to identify protocol-specific
distribution system based on the well knows “client-server                issues which out of the scope of this study [5].
architecture”. The MFTS server is actually a distribution
engine, which handles the issues related to file sharing as well
as instant messaging exchange among the various MFTS




                                                                     84                                http://sites.google.com/site/ijcsis/
                                                                                                       ISSN 1947-5500
                                                            (IJCSIS) International Journal of Computer Science and Information Security,
                                                                                                                      Vol. 8, No. 7, 2010
B. SIP as Instant Messaging Protocol                                    traverse through several proxies before it reaches the final
    The Internet Engineering Task Force (IETF) has defined              destination of the end user [1]. On the other hand, in MFTS,
two modes of instant messaging for SIP. The first is the pager          similar mechanism is used to ensure that an MFTS message
mode, which makes use of the SIP MESSAGE method, as                     will reach to the user that resided behind another MFTS [3].
defined in [6]. The MESSAGE method is an extension to the               The proposed interworking module will take the advantage of
SIP that allows the transfer of Instant Messages. This mode             these features. The idea is to combine both the proxy server
establishes no sessions, but rather each MESSAGE request is             capabilities with MFTS server capabilities in one entity. This
sent independently and carries the content in the form of               entity should also include a translation component that
MIME (Multipurpose Internet Mail Extensions) body part of               translates SIP messages to MFTS messages and vice versa. In
each request. Additionally, grouping these independent                  this case, both SIP proxy server and MFTS server will
requests can be achieved at the SIP UA’s by adding a user               communicate with this entity as a server analogous to them.
interface that lists these messages in ordered way or grouped in        Accordingly, this method will provide transparent
a dialog initiated by some other SIP request. By contrast, the          communication to the users and to the servers as well. In
session mode makes use of the Message Session Relay                     addition to that, the translation process will be done within that
Protocol or MSRP [7], which is designed to transmit a series of         bi-directional translation server. The Figure below illustrates
related instant messages of arbitrary sizes in the context of a         the general interworking prototype between SIP and MFTS.
session.

                  III.   INTERWORKING METHOD
          As mentioned previously in [8], SIP handles two
methods for instant messaging services, pager mode and
session mode. In a session mode there will be a session
                                                                                         Figure 3.   SIP-MFTS Interworking
establishment using Message Session Relay Protocol (MSRP)
while in the pager mode there is no need to establish a session,
because the MESSAGE method in SIP is actually a signaling               B. System Model
message or request which is the same as INVITE, CANCEL                      Before starting the interworking session, the translation
and OPTION. On the other hand, the MFTS server is the                   module must register itself with the SIP server and supports the
distributing engine responsible for sending instant messages            address resolution schemes of SIP. In MFTS, there are two
among MFTS users, which uses control messages for that                  types of registration. The first registration is that the MFTS
purpose. From this point, we found out that it is more stable to        server should register itself to other MFTS servers, since the
choose the SIP pager mode for instant messaging as the other            translation model is considered as another MFTS server from a
part to communicate with MFTS users. Figure 2 below shows               MFTS user’s side; it must register itself with MFTS server. The
the SIP MESSAGE request.                                                second type of registration is the process by which an MFTS
                                                                        client logs into the MFTS server, and informs it of its IP
MESSAGE sip:user2@domain.com SIP/2.0                                    address. Registration will occur before any instant messaging
Via: SIP/2.0/TCP                                                        sessions are attempted. The MFTS server will respond with
user1pc.domain.com;branch=z9hG4bK776sgdkse                              either a confirmation or a reject message. In SIP, the
Max-Forwards: 70                                                        REGISTER request allows a SIP registrar server to know the
                                                                        client’s address.
From: sip:user1@domain.com;tag=49583
To: sip:user2@domain.com
Call-ID: asd88asd77a@1.2.3.4                                            C. Interworking Module Requirements
CSeq: 1 MESSAGE                                                             Each entity in the interworking module has been analyzed
Content-Type: text/plain                                                based on its normal functionalities. According to that, Figure 4
Content-Length: 18                                                      shows the internal modules by using the use case tool of the
                                                                        proposed translation server and the number of connections to
Hello World                                                             the SIP side of the network and to the MFTS side of the
                                                                        network. As illustrated in figure 4, two modules are used for
                  Figure 2. SIP MESSAGE Request                         the registration for both SIP and MFTS, and two additional
                                                                        modules are used for sending and receiving the control
    Since both MFTS and SIP use the Transmission Control                messages, these two modules are linked together by the
Protocol (TCP) for sending and receiving control messages               translation function module to translate between the two types
(signaling) between their network components, the translation           of instant messages (MESSAGE and PRCHAT).
module should use TCP as well.

A. SIP-MFTS Interworking
   In order to ensure that a message will reach its destination,
SIP proxy server may forward a SIP message request to
another server; in other words, a SIP message request may
   National Advanced IPv6 Centre. (sponsors)



                                                                   85                                http://sites.google.com/site/ijcsis/
                                                                                                     ISSN 1947-5500
                                                                      (IJCSIS) International Journal of Computer Science and Information Security,
                                                                                                                                Vol. 8, No. 7, 2010
                                                                               between SIP and MFTS. Moreover, each test is conducted five
                                                                               times to ensure certainty.

                                                                               A. Functional Testing
                                                                                    SIP-MFTS Functional testing is basically done by sending
                                                                               several chat messages with a variety of lengths to the
                                                                               destination/s. It is applied on all proposed scenarios that were
                                                                               mentioned in subsection 5.2.1. Five different lengths of
                                                                               messages are sent through the network starting from “Hello
                                                                               world” sentence and ending with its duplications, for instance,
                                                                               the second sentence is “Hello world Hello world” and so on.
                                                                               All functional tests were done successfully.

                                                                               B. Time Required
                                                                                   This part of testing has actually followed the same
                                                                               conducted steps in the functional testing. All tests at this stage
                                                                               are done by acquiring the required time for each chat message
     Figure 4. Use Case Diagram for the Proposed Translation Server            to reach the other domain. Furthermore, each type of test is
                                                                               done five times and an arithmetic mean is calculated for them.
                                                                               Table III reports the time required for the messages to be sent
                                                                               from the SIP client to the MFTS client, while Table IV shows
D. SIP and MFTS Message Translation
                                                                               the time required for the message to be sent from the MFTS
    Both SIP and MFTS messages consist of few fields that are                  client to the SIP client. Moreover, there was no significant
used to identify the sender, the receiver or receivers and some                difference noticed in both tests (SIP to MFTS) and (MFTS to
other information, in both of them this information is                         SIP).
considered as a message header. Table I and Table II show the
translation table that translates MFTS specifications to SIP
specifications and from SIP specifications to MFTS                                                 TABLE III.    SIP TO MFTS
specifications respectively.                                                            Message Lenght                    Time (Seconds)
                                                                                       “Hello World” X1                        0.23
                                                                                       “Hello World” X2                        0.27
          TABLE I.        MFTS-TO-SIP TRANSLATION TABLE                                “Hello World” X4                        0.34
            MFTS                        SIP Header or Contents                         “Hello World” X8                        0.45
           Command                        body of MESSAGE                             “Hello World” X16                        0.43
            Thread                             Call-ID
          Sender-Info                           From
          Receiver(s)                             To
                                                                                                   TABLE IV.     MFTS TO SIP
                                                                                            MFTS                     SIP Header or Contents
          TABLE II.       SIP-TO-MFTS TRANSLATION TABLE                                “Hello World” X1                      0.29
                                                                                       “Hello World” X2                      0.28
     SIP Header or contents                       MFTS
                                                                                       “Hello World” X4                      0.26
             Call-ID                               thread
                                                                                       “Hello World” X8                      0.50
        Content-Language                       (no Mapping)
              Cseq                             (no mapping)                           “Hello World” X16                      0.39
              From                              Sender-Info
             Subject                           (no Mapping)
               To                               Receiver(s)
                                                                                            V.    CONCLUSION AND FUTURE WORK
       body of MESSAGE                           Command
                                                                                   The translation server was capable of handling a one - to -
                                                                               one instant messaging conference between SIP and MFTS.
                   IV.    TESTING AND RESULTS                                  Two types of tests were conducted; functionality test and the
    The translation server testing is based on proposing real                  time required. All tests are done successfully and were within
interoperability IM scenarios. Two tests are conducted, one to                 an acceptable range. Proposed future work might cover the
check the functionality of the system as an IM interoperability                multipoint IM sessions between SIP and MFTS (work in
module between SIP and MFTS, while the second is                               progress) and might also include the multiple-protocol
supplementary to the first one which is to know the time                       interoperability concept that involves many IM protocols
required to receive an instant message to the destination client.              communicating together. Furthermore, since MFTS has the
Both tests are applied on a one-to-one interoperability session                capability to work as a file transfer system, and since there is a
                                                                               study conducted to make SIP able to work as a file transfer




                                                                          86                               http://sites.google.com/site/ijcsis/
                                                                                                           ISSN 1947-5500
                                                                            (IJCSIS) International Journal of Computer Science and Information Security,
                                                                                                                                      Vol. 8, No. 7, 2010
system based on the capability provided by MSRP, additional                              in 2009. Her PhD research is on peer-to-peer computing. She
interworking between SIP and MFTS based on file transfer                                 has numerous research of interest such as IPv6 multicasting
capability will increase the usefulness of this study.                                   and video Conferencing.

                                REFERENCES
[1] J. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R.                                   Dr. Ahmed M. Manasrah is a senior
     Sparks, et al., " SIP: Session Initiation Protocol ", RFC 3261, June 2002.                                lecturer and the deputy director for
[2] R. Fielding, J. Gettys, J.Mogul, H. Frystyk, L. Masinter, P. Leach, et al.,                                research and innovation of the National
     “Hypertext transfer protocol–HTTP/1.1”, RFC 2616, June 1999.
[3] S. N. Saleh, “An Algorithm To Handle Reliable Multipoint File Transfer
                                                                                                               Advanced IPv6 Centre of Excellence
     Using The Distributed Network Entities Architecture” Master Thesis,                                       (NAV6) in Universiti Sains Malaysia.
     Universiti Sains Malaysia, Malaysia, 2004.                                                                He is also the head of inetmon project
[4]     “Multimedia        Conferencing       System     –    MCS”      Internet:                              “network monitoring and security
     http://www.unimal.ac.id/mcs/MCSv6.pdf,[17-September-2010].                                                monitoring platform”. Dr. Ahmed
[5] B. Campbell, J. Rosenberg, H. Schulzrinne, C. Huitema, and D. Gurle,                                       obtained his Bachelor of Computer
     “Session Initiation Protocol (SIP) Extension for Instant Messaging”, RFC
     3428, December 2002.                                                                                      Science from Mu’tah University, al
[6] B. Campbell, R. Mahy, C. Jennings, “The Message Session Relay Protocol               Karak, Jordan in 2002. He obtained his Master of Computer
     (MSRP)”, RFC 4975, September 2007.                                                  Science and doctorate from Universiti Sains Malaysia in 2005
[7] S. N. Saleh, “Semi-Fluid: A Content Distribution Model For Faster                    and 2009 respectively. Dr. Ahmed is heavily involved in
     Dissemination Of Data” PhD Thesis, Universiti Sains Malaysia, Malaysia,             researches carried by NAv6 centre, such as Network
     2010.
[8] J. C. Han, S. O. Park, S. G. Kang and H. H. Lee, “A Study on SIP-based
                                                                                         monitoring and Network Security monitoring with 3 Patents
     Instant Message and Presence” in: The 9th International Conference on               filed in Malaysia.
     Advanced Communication Technology, Korea, vol 2, pp. 1298-1301,
     February 2007.



                         AUTHORS PROFILE

                   A PhD candidate, He received his
                   bachelor degree in software engineering
                   from Mansour University College
                   (IRAQ) and a master’s degree in
                   computer science from Univeriti Sains
                   Malaysia (Malaysia). His PhD. research
                   is mainly focused on Overlay Networks.
                   He is interested in several areas of
                   research     such     as    Multimedia
                   Conferencing, Mobile Ad-hoc Network
(MANET) and Parallel Computing.

                       Dr. Omar Amer Abouabdalla obtained
                       his PhD degree in Computer Sciences
                       from University Science Malaysia
                       (USM) in the year 2004. Presently he is
                       working as a senior lecturer and domain
                       head in the National Advanced IPv6
                       Centre – USM. He has published more
                       than 50 research articles in Journals and
                       Proceedings      (International       and
                       National). His current areas of research
interest include Multimedia Network, Internet Protocol version
6 (IPv6), and Network Security.


                           A PhD candidate joined the NAv6 in
                           2010. She received her Bachelor degree
                           in computer sciences from Mansour
                           University College (IRAQ) in 2005 and a
                           master’s degree in computer sciences
                           from Univeriti Sains Malaysia (Malaysia)



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                                                                                                                   ISSN 1947-5500

				
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Description: Vol. 8 No. 6 September 2010 International Journal of Computer Science and Information Security