ISO IEC 24793-2:2010 pdf – Information technology – Mobile multicast communications: Protocol overnative lPmulticast networks
ISO IEC 24793-2:2010 pdf – Information technology – Mobile multicast communications: Protocol overnative lPmulticast networks.
In the figure. an MN is receiving multicast data packets in an MR region via the old PoA. By handoscr. the MN now moses into another MR region il gets a link.Iayer trigger for the new PoA. which may be performed with the help of the advertisement messages nt the new PoA (e.g.. BEACON message of AP in the WLAN network, or pilot channel of Base station in the 36 wireless nelworkt, This is called movement detection’. Then an appropriate authentication pnicess may be perfuaned. which is specific to the underlying wireless access system.
In the %iewpuint of MMCP, ftr the movement detection, the MN begins the haiahser operations by sending an I-fIR message to the old LMC. The HIR message shall include the information about the new PoA (e.g.. link-layer MAC address or ID of PnA such as line ID, BSSIL) of AP, etc.).
On receipt of an I-Ilk message from the MN. the LMC will identify which suhnct the MN is going In move into. The old LMC can idenrify the new LMC by using the address of ID 411 the new PoA which is contained in the HIR message It is noted that the LMCs in MMCP are pre-deployed and preconfigured by the corresponding services provider. Accordingly, it is assunied that each LMC will share all the infiwmation with other l.MCs. The examples of thc contact information include the MAC and IP address of LMC. and also the MAC addresses and lI)s for the PuAs associated with each LMU.
Based on the ,nfiwrnat,on described above, the old LMC shall send a HUT message to the new LMC. The HUT message shall include the inftwmation about the II) of the MN and the group address used for the multicas data channel.
On receipt of an HUt message, the new LMC will perform the IGMPMLI) join operation to the new MR as an agent of the MN. This is done for thc MN to receive the inulticast data pockets in the newly visited suNset as soon as possible. After that, the new LMC will respond to the old LMC with Lhe IITA message. In turn, the old LMC will send an IIIC message to the MN. This will complete the handoser operation for mobile multicasting.
After lurther movement toward the new PoA. the MN will complete the layer 2 (L2) and Layer 3 (L3) movement By this, Ihc MN will establish the new 1.2 and 1.3 connection (with a new IP address of MNI. Then the MN pcrfomis the session join and local join operations, as described in clause 7.2.
For reliable transmission of MMCP n1ev’ges for handover support, the handover initiation time t HIT) timer is used by the MN br the HIR and the HIC messages, and the contest transfer time ((iT) timer is used by the old LMC for HUl’ and HTA messages. After sending an HIR message to the old L.MC, the MN waits for the responding HIC message for HIT time. The MN will retransmit the IIIR message to the old LMC, if there is no responding IIIC message before the HIT timer expires. In a similar way, after sending an HUT message to the new LMC. the old LMC vs-ill wait for the responding HTA message from the new LMC for CTJ time. The HIT and timers may be locally configured by he MN and the LMC.
It is noted that the handover support of MMCP can he applied to the horiiontal handover thandover between homogeneous access networks. e.g.. between PoAs within the 36 wireless networkat as well as the vertical handover (between heterogeneous access networks. e.g.. between 36 wireless and mobile WiMax). In case of vertical handover. an MN is equipped with the two different types of network interlaces. In this case, the detection of a new PoA and he MMCP handover operations can be easily performed since the MN could be connected to both of access networks (including the concerned two PoAs and two MRst in the overlapping region. In case of hcwi,ontal handover. the MMCP handover operations need to use an appropriate litsk.Iayer trigger such a. Link-Up or Link-Down event, which are addressed in the IEEE Xt)2.21 MIH tmedia independent handovcr). With the help of such a link-layer trigger, the MN can detect its movement to a new link or network, and it can begin the handovcr support operations by sending the HIR message to the old LMC.
In the MMCP handover. the handover performance. such as packet loss and handover latency during handoser. might depend on several factors which include the overlapping time interval in the han&ncr region and the underlying link layer technology. For example. when the overlapping time interval in the handovcr region is large enough to complete the handoser operations, the MN could benefit front seamless services during handover Otherwise, the MN might experience a certain amount of packet losses during handnvcr. In case of horirontal handover. if the underlying link layer supports a soft handover, the haisdover perforntatsce for the MN can be nwwe enhanced, Further issues on handover performance are outside the scope ni MMCP.