I try to keep a record of my observations of wireless things happening around the world, in particular in Malaysia. My interests are broadband wireless access (BWA), 3G cellular communications, wireless sensor networks and vehicular ad-hoc network (VANET).

Thursday, November 08, 2007

Wimax: sharing of infrastruture by service providers

Malaysia's four Wimax licence holders (Asiaspace Dotcom Sdn Bhd, Redtone-CNX Broadband Sdn Bhd, Bizsurf (M) Sdn Bhd (a unit of YTL Corp) and Packet One Networks Sdn Bhd (formerly known as MIB Comm)) have set up a consortium to build a common infrastructure for their wireless broadband service.

As the Wimax ISP are providing service in different location, it is not possible for them to share the transmit towers or base station locations. However, they can share the usage of high speed backbone network. This make economic sense from trunking point of view as the backbone connection may not be fully utilised by any operator at any moment.

3 comments:

Anonymous said...

Dear blogger,

Iread thru this entry of urs, and cud not help but wonder, is a fiber-trunk really necessary for WiMAX providers? I took an excerpt from the newspaper cutting that u have attached in the entry:

"He (Lim King Yaik) said Wimax players would still be hampered because they did not have total ownership of the backhaul trunk fibre."

Can you please comment on this need?

Thank you,
Angel

emlsim said...

In fact, the original idea of Wimax was to use Point to Multipoint or Point to point Wimax link to serve as backhaul connection. Mesh WiMax link can also be used to improve reliability.

However, due to the limited bandwidth allocated to service provider (30MHz for both uplink and downlink), if we use some of the bandwith for backhaul, the network planning will become much more difficult. For example, assume TDD mode is used (since I did not notice another band allocated at 50MHz or higher away), then the operators may divide the 30MHz into 3 channels each with 10MHz bandwidth, for provisioning of service.

Well, 3 channels are already small enough and tough in terms of optimum network planning and minimising co-channel interference and adjacent channel interference, let alone if we take one channel out to be used as backhaul connection. Thus, the service provider has to use alternative backhaul connection, such as the conventional lease line or fiber link.

Well, if the 3 WiMax service providers in Malaysia work together, the situation may be different. Note that Bizsurf was awarded the 2330 to 2360 bandwidth, MIB 2360 to 2390 MHz, and Asiaspace 2300 to 2330 MHz. If Bizsurf and MIB or Asiaspace and MIB work together, the pool of bandwidth will be higher. Some bandwidth can be used as backhaul.

However, there is no trunking gain if Bizsurf and Asiaspace work together since both are operating at the same frequency band. They most likely will compete for coverage area.
However, if they cooperate, they can reduce interference and maximize individual network performance.

emlsim said...

In fact, the original idea of Wimax was to use Point to Multipoint or Point to point Wimax link to serve as backhaul connection. Mesh WiMax link can also be used to improve reliability. By doing so, the deployment cost would be lower.

In fact, according to WiMax forum, the first phase of WiMax usage is expected to be focused on serving as backhaul connections! not as last mile access for subscribers due to economic reason.