Changes...

I got a new task for my final project. I got to make some change in the current 3G base station and 3G device implementation.

The changes are :-
1) bandwidth for the link between the bs and mobile node
2) the incoming connection from a mobile node will be defer and packet loss or drop will occur.
3) each mobile node is allocated some of the total bandwidth
3) the bandwidth is return when mobile node disconnects from the bs.

How? where? what?

Handover latency

Mana aku nak cari nilai handover latency ni. Aku baru halfway cari kat ts 25 series kat 3gpp.org. aku ada gak cari kat journal dr ieee. so far tak jumpe lagi. argh geram aku..namun usaha harus teruskan.

aku nak jerit kuat2.....arghhhhhhhhhhhhhhhhhhhh gerammnya aku.........

Codes...

I have not write something in this blog for a while. So what I did for my project in the last seven days? I have to understand the source code in the simulator in order to make some changes which I dont know where I must changes. As recommended by the developer, I study the SoftRadio class which is responsible in deciding whether it must connect to the WLAN access points or the 3G base station. It is assummed in the simulator the 3G radio will have more coverage than the WLAN. However, WLAN has much bigger bandwidth than the 3G radio. WLAN connection are usually deploy inside a buidling. Both WLAN and 3G are modeled in Java programming language on certain important parameters and less important attributes are omitted out.

I'm currently trying simulate Fast Handover for Mobile IPv6 which can do a vertical handover between WLAN ap and 3G base station using MIRAI-SF simulator. The current version has problem in connecting with the WLAN ap. The developer has decided not to maintain the SoftRadio class but concentrate on developing Media Independant Handover (MIH) for next release of the simulator. The next thing that I have to do is to implement some methods so that bitrate for the 3G link can be set.

So I have managed to identified part of the problem, there are methods inside the WLANRadioDevice class return only null value. The methods does contain any implementation to evaluate a certain scenario. For example, the findAccessPoint method immediately return a null value which cause the SoftRadio class to select the 3G interface most of time. I reckon my next step, is to find out how i can make the SoftRadio class to initiate a WLAN connection using the available package. I thinking using the wlan package which is only availabe in MIRAI-SF. With this package, I can take the advantage of using the IEEE802.11 standard implementation.