Thursday, January 31, 2008


Below are the details of the result of the commissioning of new wireless antenna radios and the testing of Bellevue’s backup Internet connection via Plaza B, Northgate Cyberzone by the FITI Group.

The new wireless antennae, Ovislink AirLive, were successfully commissioned on the afternoon of January 17, 2008. The wireless link that connects Bellevue to Plaza B was restored at around 2pm by replacing the old radio antennae that were reported having intermittent wireless link a few months back. The new Ovislink Airlive antenna registered a stable RSSI of –50dbm and the result of PING across the wireless link indicated a steady radio-to-radio link.

>From the 3Com hub at the Roof Deck, the testing of Internet was successful with our laptop connected to one if its ports. All PING to (1 & 2)Airlive radios, (3) Northgate router, (4) a test PC, and the Internet were all successful. Iperf were also conducted and registered a throughput of up to 10mbps. The testing was conducted twice (January 17 & 18) which lasted for almost 3 hours on each occasion and the link was observed to be stable based on the aforementioned diagnostics conducted. Attached herewith are all the snapshots taken during the testing for your reference.

The connection, however, encountered problem when we transferred the connection from our laptop to the BelleVue network via the 3Com hub and your LAN extender. While the link remained connected and stable at the RF level, our PING to each hop points timed out. During this time, we observed that all the IP addresses that we are PING-ing would register a MAC address in the ARP table of our router and our laptop that is not their own. All four IP addresses appeared on the ARP table with a single "unidentified MAC address". The PING would restore only when we remove it from the 3Com hub, at which time our devices will restore its original and correct respective MAC addresses.

To try to resolve this, we changed the IP address settings of our router and radios but resulted to the same problem. We suspect that the switch that your LAN extender is connected to a router do not have proper VLAN configuration or there is a device or a PC that is causing this kind of malicious network activity.

This report is being provided to you to both inform you that the wireless link problem had been resolved, and to seek your attention about the problem above-mentioned.

Thank you very much.

Sanny Sison


The Bellevue link problem was finally resolved after months of speculations. The internal LAN problem at Bellevue, however, persisted, and shall be handled by their own IT people.

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