fast tree join for seamless multicast handover in fmipv6-based … · 2017-02-11 · i....
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I. INTRODUCTION
With rapidly growing wireless communications, to
support seamless handover becomes one of the crucial
issues to be addressed [1],[2]. The Mobile IPv6 (MIPv6)
[3] was designed to manage the movement of mobile
nodes in the network. To improve handover performance
of MIPv6, the Fast Mobile IPv6 (FMIPv6) was proposed
[4]. FMIPv6 is primarily used to reduce the handover
latency in the 'unicast' networks, whereas the issues on
multicast handover support in the mobile networks are still
for further study.
For support of IP multicasting, a lot of schemes have
been proposed, which include the Internet Group
Management Protocol (IGMP) [5],[6] and Multicast
Listener Discovery (MLD) [7],[8] for multicast group join
and leave, and also several multicast routing protocols for
construction of multicast trees such as Protocol Independent
Multicast [9] and Source Specific Multicast [10].
It is noted that a lot of schemes have been proposed to
support mobile multicasting in MIPv6-based networks,
which can be classified into the following two approaches:
Remote Subscription (RS) and Bi-Directional Tunnelling
(BT). In the RS scheme, a mobile node (MN) will join the
multicast tree in the newly visited network. This RS
scheme does not require the packet encapsulation, since it
does not use the MIP Home Agent (HA) and tunnelling,
and it also gives an optimal multicast forwarding path
from a multicast source to many mobile receivers. These
benefits come from the explicit join to the multicast tree,
993
This paper proposes a fast tree join scheme to provide seamless multicast handover in the mobile networks using the
Fast Mobile IPv6 (FMIPv6). In the existing FMIPv6-based multicast handover schemes, the bi-directional tunnelling or
the remote subscription is employed with the packet buffering at the new access router (AR). In general, the remote
subscription approach is preferred to the bi-directional tunnelling, since in the remote subscription scheme we can
exploit an optimized multicast path from a multicast source to many mobile receivers. However, in the remote
subscription scheme, if the tree joining operation takes a long time, a significant amount of data packets will be buffered
at the new AR, and thus it may result in the buffering overhead that may induce the buffer overflow and packet losses.
In this paper, we propose a fast join to multicast tree so as to reduce the handover delay and the associated buffering
overhead. In the proposed scheme, the new AR will join the multicast tree as soon as the associated handover event is
detected. This ensures that the new multicast data packets can arrive at the new AR as fast as possible, which is helpful
to reduce the packet buffering overhead as well as the handover delay. From the ns-2 simulations, it is shown that the
proposed scheme can give better performance than the existing FMIPv6-based multicast handover schemes in terms of
handover delay and buffering overhead.
Keywords: Mobile multicast, FMIPv6, Fast tree join, Handover delay, Buffering overhead
논문번호: TR09-106 논문접수일자:2009.09.07, 논문수정일자:2010.06.30, 논문게재확정일자:2010.10.19
Moneeb Gohar, Sang Tae Kim, Seok Joo Koh: Kyungpook National University
Fast Tree Join for Seamless Multicast Handover
in FMIPv6-based Mobile Networks
Moneeb Gohar ·Sang Tae Kim ·Seok Joo Koh
not using the MIP tunnelling. However, some multicast
data packets may be disrupted during the tree join process.
On the other hand, the BT scheme uses the MIP HA, in
which MN receives the data packets using the bi-
directional (unicast) tunnelling from the HA in the point-
to-point fashion. This BT scheme requires much overhead
for packet encapsulation at HA, and also the multicast
packet delivery path between a multicast source and a
mobile receiver is not an optimum.
In fact, the BT scheme for MIP-based multicast
handover has also the 'tunneling convergence' problem, in
which the duplicate packets will arrive at MNs, even
though they have subscribed to the same multicast group
[11]. To solve this problem, the Mobile Multicast (MoM)
protocol was proposed in [12], in which a new agent
called 'Designated Multicast Service Provider (DMSP)' is
employed in the remote network so as to forward the
multicast packets from HA to MNs. The idea behind this
approach is to decrease the number of duplicated multicast
packets toward MNs in the HA side. The 'Range Based
Mobile Multicast (RBMoM)' [13] was also proposed to
find out the optimal trade-off between the shortest delivery
path and the low frequency of multicast tree rebuilding, in
which an agent called 'multicast home agent (MHA)' is
introduced.
Some more works have been done to improve the
MIP-based mobile multicasting scheme. In the 'Multicast
by Multicast Agent (MMA)' protocol [14], the two agents
were separately used: Multicast Agent who joins the
multicast group, and Forwarding Agent who forwards the
multicast data packets to MNs. Another proposal is the
'Timer-Based Mobile Multicast Protocol (TBMoM)' [15],
which is purposed to find out a trade-off between the
shortest path delivery and the disruption period of
multicast packet delivery. In this scheme, a new agent
called Foreign Multicast Agent (FMA) is introduced so as
to decrease the disruption period, which selectively use the
tunnelling between FMAs or the remote subscription. By
the way, compared to the MIP-based mobile multicasting,
the studies on FMIPv6-based mobile multicasting have not
been done enough yet.
In this paper, we propose a fast tree join scheme to
provide seamless multicast handover in the mobile
networks using the Fast Mobile IPv6 (FMIPv6). The
proposed scheme can be used to reduce the handover
delays and the associated packet buffering overhead
during handover. By the ns-2 simulations, we compare
the proposed scheme with the existing schemes in terms of
handover delay and buffering overhead.
The rest of this paper is organized as follows. Section
II reviews the existing works on the FMIPv6-based mobile
multicasting. Section III describes the proposed scheme in
details. Section IV evaluates the performances of the
existing and proposed schemes by ns-2 simulations.
Section V concludes this paper.
II. EXISTING FMIPv6-BASEDMULTICAST HANDOVERS
In this paper, we note the scheme of FMIPv6-based
multicast handover that was proposed in [16], which is
denoted by 'FMIP-M' in this paper. In particular, we will
focus on the following two schemes: Bidirectional
Tunnelling (BT) and Remote Subscription (RS), which are
based on the packet forwarding for multicast handover.
In the FMIP-M scheme, as shown in Figure 1 and 2,
the following operations are commonly applied to both of
the BT and RS schemes. First, MN will receive an L2
trigger from the network, and sends a Router Solicitation
for Proxy (RtSolPr) to the Previous Access Router (PAR).
The PAR replies to MN with a Proxy Router
Advertisement (PrRtAdv). MN then obtains a new care of
address. The fast handover procedure actually starts by
sending a Fast Binding Update (FBU) message towards
PAR that contains a multicast group address. Given the
information contained in the FBU message, PAR sends a
Handover Initiation (HI) message to the New Access
Router (NAR). The NAR will check the validity and
uniqueness of the nCoA. After that, NAR can reply to
PAR with a Handover acknowledgement (HACK)
message. The HACK message contains the sequence
number of data packets to be forwarded. This sequence
number represents the sequence number of the first packet
that will be stored in the NAR buffer. PAR then sends the
Fast Binding Acknowledge (F-BACK) message to MN
and NAR both.
After sending the F-BACK message, the PAR begins to
forward multicast data packets to NAR. The subsequent
operations are different for each of the two cases: FMIP-M-
BT (See. Figure 1) and FMIP-M-RS (See. Figure 2).
In the FMIP-M-BT scheme of Figure 1, PAR starts to
forward the multicast packets (received via the bi-
directional tunnelling from the HA) to NAR. This packet
forwarding will be continued, until PAR receives the HO
COMPLETE message from NAR. This HO COMPLETE
message will be triggered only when NAR receives the
Unsolicited Neighbour Advertisement (UNA) message
from MN, and also it completes the MIPv6 Binding
Update (BU) operation with HA, as indicated in the figure.
Fast Tree Join for Seamless Multicast Handover in FMIPv6-based Mobile Networks 994
data packets are now delivered to the NAR by using the
newly configured multicast tree. During the tree join or
configuration time, PAR will also forward the multicast
packets to NAR. The subsequent operations include the
transmission of HO COMPLETE message from NAR to
MN and UNA message from MN to NAR, and the
delivery of buffered data packets from NAR to MN.
After this, the buffered data packets will be forwarded by
NAR to MN.
In the FMIP-M-RS scheme of Figure 2, NAR sends a
tree join message (e.g., PIM JOIN) to the upstream
Rendezvous Point (RP), as shown in the figure. For the
join message, the RP will respond to NAR with a Join
ACK (PIM JOIN-ACK) message, and then the multicast
995 Telecommunications Review·Vol. 20 No. 6·2010. 12
MN PAR NAR HA
Packet Forwarding
Multicast Data Delivery
Figure 1. FMIP-M handover using the bidirectional tunnelling (BT)
Tunneling
RtSolPr
PrRtAdv
FBUHI
HACK
FBACK
Buffering
FBACK
LINK DOWN
LINK UP
UNABUBU ACK
HO COMPLETE
MN PAR NAR RP
Packet Forwarding
Multicast Data Delivery
Multicast Tree Data
Figure 2. FMIP-M handover using the remote subscription (RS)
PIM JOIN
PIM JOIN ACK
RtSolPr
PrRtAdv
FBUHI
HACK
FBACK
Buffering
FBACK
LINK DOWN
LINK UP
UNA
HO COMPLETE
scheme, NAR will begin the tree join operation just when
it receives HI message from PAR. Accordingly, if the tree
joining process is completed before NAR receive the
FBACK message from PAR, PAR does not need to
forward the data packets to NAR, since NAR can receive
the multicast data packets directly from the multicast tree.
Figure 3 shows the basic operations of the proposed
FMIP-FTJ-RS scheme in case that the tree join operation
is completed relatively earlier. In the figure, MN initiates
the multicast handover by sending the RtSolPr message to
PAR. The RtSolPr message contains both the FBU option
and the multicast address, as shown in Figure 4. Note that
the handover latency could be more reduced by
encapsulating the FBU option into the RtSolPr message.
After receiving the RtSolPr message, PAR sends the
PrRtAdv message to MN. In addition, PAR will send the
HI message to the NAR. When receiving the HI message,
the NAR will immediately respond with the HACK
message to PAR, and at the same time, it begins the tree
joining process to RP by sending the PIM JOIN message it
will receive the responding PIM JOIN-ACK message from
the upstream RP.
In the proposed scheme, if the tree joining operation is
completed earlier (i.e., NAR can receive the multicast data
packets from the multicast tree, before it receives the
FBACK message from PAR), the NAR sends the HO-
COMPLETE message to PAR in this case PAR does not
need to perform the packet forwarding to NAR.
Fast Tree Join for Seamless Multicast Handover in FMIPv6-based Mobile Networks 996
In the existing schemes, the packet buffering may be
subject to the 'buffer overflow' at the buffer of NAR. That
is, during the handover, NAR will continue to buffer the
data packets forwarded from PAR, until the MIPv6 BU
operation (in case of BT) or the PIM Join operation (in
case of RS) is completed. As the MIPv6 BU or PIM Join
time gets larger, the buffering of NAR may induce the
buffer overflow and thus a significant amount of data
losses. Moreover, the existing two schemes tend to give
large handover delays.
In this paper, we propose a fast join to multicast tree
so as to reduce the handover delay and buffering overhead
during handover. In the proposed scheme, NAR will try to
join the multicast tree as soon as the handover event is
detected (i.e., when NAR receives HI message from PAR).
III. PROPOSED FAST TREEJOIN FOR MULTICASTHANDOVER
In this paper, we propose a fast tree join scheme for
seamless multicast handover, which is based on the
existing RS scheme and thus denoted by 'FMIP-FTJ-RS' in
this paper. The main idea of the proposed scheme is that
NAR begins the tree join process as fast as possible, so as
to the new multicast data packets arrive at the NAR earlier
over the optimized multicast data path. In the proposed
MN PAR NAR RP
Multicast Tree Data
Multicast Packet Delivery
Figure 3. Proposed FMIP-FTJ-RS scheme (early completion of tree join)
RtSolPr[FBU]
PrRtAdv HI
HACK
FBACKFBACK
PIM JOIN
Buffering
PIM JOIN ACK
HO COMPLETE
LINK DOWN
LINK UP
UNA
simulation, as shown in Figure 6. In the figure, a
correspondent node (CN) is communication with MN, and
the MN is initially in the remote network of PAR, and then
it moves into the NAR network by handover. For simple
comparison of BT and RS schemes, it is assumed that HA
is co-located with RP.
For simulation, a variety of parameters are set as follows.
The fixed/wired link between CN and HA/RP is set to
10Mbps of network bandwidth and 10ms of transmission
delay. The links between HA/RP and AR are all set to
5Mbps of bandwidth and 20ms of transmission delay. The
wireless links between AR and MN are all are set to 1Mbps
of bandwidth and 5ms of transmission delay. In addition, the
link between PAR and NAR is set to 5 Mbps of bandwidth
and 10 ms of transmission delay. The link switching delay
from PAR to NAR by handover is set to 150ms.
Otherwise, if the tree joining process has not been
completed until NAR receives the FBACK message from
PAR, some of the multicast data packets may be
forwarded by PAR to NAR, as done in the existing FMIP-
M-RS scheme, as shown in Figure 5.
In both of the two cases, it is noted that the fast tree
join to the multicast tree can ensure that the number of
data packets buffered at NAR and the overall handover
delay will be reduced, compared to the existing schemes.
IV. SIMULATION RESULTS
In this section, we present the performance analysis of
the proposed scheme using ns-2 network simulator [17].
We first consider a simple network topology used for ns-2
997 Telecommunications Review·Vol. 20 No. 6·2010. 12
Figure 4. RtSolPr message including the FBU option
Type Code Checksum
Subtype Reserved Identifier
LLA Option
FBU Option
Multicast Address
MN PAR NAR RP
Packet Forwarding
Multicast Packet Delivery
Multicast Tree Data
Figure 5. Proposed FMIP-FTJ-RS scheme (late completion of tree join)
PIM JOIN
PIM JOIN ACK
RtSolPr[FBU]
PrRtAdv HI
HACK
FBACK
Buffering
FBACK
LINK DOWN
LINK UP
UNA
HO COMPLETE
Fast Tree Join for Seamless Multicast Handover in FMIPv6-based Mobile Networks 998
Figure 7 shows the simulation results, which depicts
the sequence numbers of data packets that MN has
received from CN, for the three candidate schemes: FMIP-
M-BT, FMIP-M-RS, and FMIP-FTJ-RS.
From the figure, we can see the handover delays
experienced by MN during handover for the three
candidate schemes. In the FMIP-M-BT scheme, the
handover delay occurs in the time interval from 29.94
second to 30.16 second, which approximately corresponds
to the handover delay of 220ms. Similarly, the FMIP-M-
RS scheme gives the handover delay of 210ms. On the
other hand, the proposed FMIP-FTJ-RS scheme gives the
handover delay of 160ms. Accordingly, the proposed
scheme can reduce the handover delays of the existing
schemes approximately by 50ms~60ms. Note that these
gaps of handover delays are relatively large values,
compared the wireless link delay of 5 ms, which is
configured in the simulation.
Figure 8 shows the handover delays of the candidate
schemes for different link switching delays, which varies
from 100ms to 550ms. From the figure, we can see that
both of the existing FMIP-M-BT and FMIP-M-RS
CN
PAR
MN MN
NAR
HA/RP
10Mbps, 10ms
5Mbps, 10ms
handover
Figure 6. Simulation topology
1Mbps, 5ms 1Mbps, 5ms
5Mbps, 20ms 5Mbps, 20ms
7810
7800
7790
7780
7770
7760
7750
7740
7730
7720
7710
FMIP-M-BTFMIP-M-RS
FMIP-FTJ-RS
29.8 29.9 30 30.1 30.2 30.3
Simulation Time(seconds)
Figure 7. Traces of data packets received by MN during handover
Packet Sequence Number
999 Telecommunications Review·Vol. 20 No. 6·2010. 12
scheme, as the transmission delay of TAR-MN gets larger.
On the other hand, the two RS-based schemes, FMIP-M-
RS and FMIP-FTJ-RS, give almost the same performance.
Figure 10 shows the handover delays of the candidate
schemes for transmission delays between AR and HA/RP
(TAR-RP). Similarly to the results of Figure 9, the RS-
based schemes, FMIP-M-RS and FMIP-FTJ-RS, give
smaller handover delays than the BT-based FMIP-M-BT
scheme, as the transmission delay of TAR-RP gets larger.
On the other hand, the proposed FMIP-FTJ-RS scheme
provides slightly better performance than the existing
FMIP-M-RS scheme.
Now, we compare the performance of the buffering
schemes give almost similar handover delays for all the
link switching delays. In the meantime, the proposed
FMIP-FTJ-RS scheme provides smaller handover delays
than the existing two schemes. Moreover, the gaps of
handover delays between the existing and proposed
schemes get larger, as the link switching time increases.
Figure 9 shows the impacts of the wireless
transmission delay between AR and MN (TAR-MN) on the
handover delay, which compares the handover delays of
candidate schemes, as TAR-MN gradually increases from
5ms to 470ms. From the figure, we can see that the RS-
based FMIP-M-RS and FMIP-FTJ-RS schemes give
smaller handover delays than the BT-based FMIP-M-BT
1200
1000
800
600
400
200
0
FMIP-M-BT
FMIP-M-RS
FMIP-FTJ-RS
100 150 200 250 300 350 400 450 500 550
Link Switching Time(ms)
Figure 8. Handover delays for different link switching times
Handover Delay(ms)
2000
1800
1600
1400
1200
1000
800
600
400
200
0
FMIP-M-BT
FMIP-M-RS
FMIP-FTJ-RS
5 10 20 40 70 110 160 220 290 370 470
TAR-MN(ms)
Figure 9. Handover delays by transmission delay between AR and MN
Handover Delay(ms)
Fast Tree Join for Seamless Multicast Handover in FMIPv6-based Mobile Networks 1000
overhead for each of the candidate schemes, which is
measured by the number of data packets buffered at NAR
during handover.
Figure 11 compares the amount of data packets
buffered at NAR for different link switching times. In the
figure we can see that the number of buffered packets
becomes larger, as the link switching time increases, since
the handover delay gets larger. However, we note that the
proposed FMIP-FTJ-RS scheme gives much smaller
buffering overhead than the existing FMIP-M-BT and
FMIP-M-RS schemes, as the link switching time
increases. This is because the proposed scheme performs
a faster tree join than the existing schemes, and thus the
amount of buffered packets can be reduced, compared to
the existing schemes. The gap of the buffering overhead
gets larger, as the link switching time increases.
Figure 12 compares the buffering overhead of the
candidate schemes for different transmission delay
between AR and MN (TAR-MN). In the figure, we can see
that the buffering overhead tends to increase for all the
schemes, as TAR-MN gets larger. It is noted that the RS-
based FMIP-M-RS and FMIP-FTJ-RS schemes give
smaller buffering overheads than the BT-based FMIP-M-
BT scheme. The two RS-based schemes, FMIP-M-RS and
FMIP-FTJ-RS, give almost the same performance.
Figure 13 compares the buffering overheads of the
3000
2500
2000
1500
1000
500
0
FMIP-M-BT
FMIP-M-RS
FMIP-FTJ-RS
10 20 40 70 110 160 220 290 370 470
TAR-RP(ms)
Figure 10. Handover delays by transmission delay between AR and RP
Handover Delay(ms)
300
250
200
150
100
50
0
FMIP-M-BT
FMIP-M-RS
FMIP-FTJ-RS
100 150 200 250 300 350 400 450 500 550
Link Switching Time(ms)
Figure 11. Comparison of buffer overhead for different link switching times
Number of Packets Buffered at NAR
seamless multicast handover in the FMIPv6-based
wireless/mobile networks. In the existing schemes using
the bi-directional tunnelling or the remote subscription
rely on the packet buffering at the new access router
during handover, which may tend to incur a large
buffering overhead and also a large handover delay. In the
proposed scheme, the new access router will join the
multicast tree as soon as a mobile node detects a new AR
by handover. This ensures that the new multicast data
packets can arrive at the new AR as fast as possible, which
is helpful to reduce the packet buffering overhead as well
as the handover delay. From the ns-2 simulations, it is
shown that the proposed scheme can reduce the buffering
candidate schemes for different transmission delays
between AR and HA/RP (TAR-RP). From the figure, we
can see that the RS-based FMIP-M-RS and FMIP-FTJ-RS
schemes give smaller buffering overheads than the BT-
based FMIP-M-BT scheme, as the transmission delay of
TAR-RP gets larger. On the other hand, the proposed
FMIP-FTJ-RS scheme provides slightly better
performance than the existing FMIP-M-RS scheme.
V. CONCLUSION
This paper proposed a fast tree join scheme for
1001 Telecommunications Review·Vol. 20 No. 6·2010. 12
500
450
400
350
300
250
200
150
100
50
0
FMIP-M-BT
FMIP-M-RS
FMIP-FTJ-RS
5 10 20 40 70 110 160 220 290 370 470
TAR-MN(ms)
Figure 12. Comparison of buffer overhead for different TAR-MN
Number of Packets Buffered at NAR
800
700
600
500
400
300
200
100
0
FMIP-M-BT
FMIP-M-RS
FMIP-FTJ-RS
10 20 40 70 110 160 220 290 370 470
TAR-RP(ms)
Figure 13. Comparison of buffer overhead for different TAR-RP
Number of Packets Buffered at NAR
overhead and the handover delays significantly, compared
to the existing FMIPv6-based multicast handover
schemes.
AcknowledgementThis research was supported by the IT R&D program
of MKE/KEIT(10035245: Study on Architecture of Future
Internet to Support Mobile Environments and Network
Diversity) and the ITRC program of MKE/NIPA(NIPA-
2010-C1090-1021-0002).
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efficient multicast support scheme for FMIPv6,''Proceeding of INFOCOMM2006, 2006, pp. 1-12.
[2] Nicolas Montavont and Thomas noel, ''Handover Management for Mobile Nodes in IPv6 Networks,''IEEE Communication Magazine, Vol. 40, No. 8, Aug. 2002, pp. 38-43.
[3] D. Johnson, et al., Mobility Support in IPv6, IETF RFC 3775, Jun. 2004.
[4] R. Koodli, Mobile IPv6 Fast Handovers, IETF RFC 5268, 2008.
[5] W. Fenner, Internet Group Management Protocol, IETFRFC 2236, November 1997.
[6] B. Cain, S.Deering, et al., Internet Group Management Protocol, IETF RFC 3376, Oct. 2002.
[7] S.Deering, et al., Multicast Listener Discovery (MLD) for IPv6, IETF RFC 2710, Oct. 1999.
[8] R. Vida, and Costa, Multicast Listener Discovery Version 2 (MLDv2) for IPv6, IETF RFC 3810, Jun. 2004.
[9] T.Pusateri, Protocol Independent Multicast - Sparse Mode (PIM-SM), IETF RFC 4602, Aug. 2006.
[10] H. Holbrook and B. Cain, Source-Specific Multicast for IP, IETF RFC 4607, Aug. 2006.
[11] I. Romdhani, et al., ''IP mobile multicast: challenges and solutions,'' IEEE Communications, Vol. 6, No. 1, 2004, pp. 18-41.
[12] T. Harrison, et al., ''Mobile multicast (MoM) protocol: multicast support for mobile hosts,'' Proceeding of ACM/IEEE Mobile Computing and Networking (MobiCom 97), Sep. 1997, pp. 151-160.
[13] Y.-J. Suh, et al., ''An efficient multicast routing protocol in wireless mobile networks,'' ACM Wireless Networks, Vol. 7, No. 5, Sep. 2001, pp. 443-453.
[14] C. R. Lin and K. M. Wang, ''Mobile multicast support in IP networks,'' IEEE INFOCOM 2000, Mar. 2000,
pp. 1664-1672.[15] J. Park and Y.-J. Suh, ''A Timer-based mobile multicast
routing protocol in mobile network,'' Computer Communications, Vol. 26, Issue 17, Nov. 2003, pp. 1965-1974.
[16] S. Yoo and S. Shin, ''Fast Handover Mechanism for Seamless Multicasting Services in Mobile IPv6Wireless Networks,'' Wireless Personal Communications, Vol. 42, 2007, pp. 509-526.
[17] NS-2 Network Simulator, http://www.isi.edu/nsnam/ns/
Fast Tree Join for Seamless Multicast Handover in FMIPv6-based Mobile Networks 1002
Moneeb Gohar
He received B.S. degree in Computer Science from
University of Peshawar, Pakistan, and M.S. degree in
Technology Management from Institute of Management
Sciences, Pakistan, in 2006 and 2009, respectively. He is
now as a Ph.D. student with the School of Computer
Science and Engineering in Kyungpook National
University, Korea. His current research interests include
Mobile Multicasting and Internet Mobility.
E-mail: [email protected]
1003 Telecommunications Review·Vol. 20 No. 6·2010. 12
Seok Joo Koh
He received B.S. and M.S. degrees in Management
Science from KAIST in 1992 and 1994, respectively. He
also received Ph.D. degree in Industrial Engineering from
KAIST 1998. From August 1998 to February 2004, he
worked for Protocol Engineering Center in ETRI. He is
now an Associate Professor at the School of Computer
Science and Engineering in the Kyungpook National
University since March 2004. His current research
interests include the architecture and mobility control for
Future Internet, Mobile Multicasting, and mSCTP
handover. He has so far participated in the International
standardization as an editor in ITU-T SG13 and ISO/IEC
JTC1/SC6.
E-mail: [email protected]
Sang-Tae Kim
He received B.S. and M.S. degrees in School of Electrical
Engineering and Computer Science from Kyungpook
National University in 2005 and 2007, respectively. He is
now a Ph.D. candidate at Electrical Engineering and
Computer Science in the Kyungpook National University.
His current research interests are the mobility support for
the locator/identifier separation protocol (LISP) and
routing scalability of LISP.
E-mail: [email protected]