Fix wireless network performance issues - Intel Dual Band Wireless-AC 7260

I was experiencing wireless network performance issues by using my laptop (Windows 7) with Intel Dual Band Wireless-AC 7260. It's slow to detect 5GHz network (802.11n) and only achieved 60~70Mb/s on 100Mb/s internet connection.

After searching the Internet, a post is extremely helpful. I followed the instructions and made the following changes:

• Removed the Intel Pro/Set software. Just use the built-in wireless network driver (17.0.5.8) with the Windows 7 OS.
• Then from the advanced settings of Device Manager: Several changes needed to be made in the advanced settings of Device Manager
• enable WMM QoS
• enable HT Mode
• disable U-APSD support

• Under Power Management in Device Manager you should uncheck “Allow the computer to turn off this device".

After making the changes, I'm now able to measurement the download speed at 90Mb/s, and it's quickly connected with 5GHz network.

Announcing the Next Generation of Oracle Engineered Systems

Oracle VM: Rethink Virtualization

Oracle VM Manager 3.3 - Improvements on MAC Address Allocation

We announced Oracle VM 3.3 earlier today. Here I'd expand one feature enhancement which was delivered as part of the large networking implementation, and it brings significant benefit to simplify virtual NIC creation. Now with Oracle VM Manager 3.3, you can coordinate with other Oracle VM Manager 3.3 instances to avoid any potential MAC address collision.

1. By default MAC addresses are automatically created using random numbers Oracle VM Manager chooses a MAC address using random numbers within the specified range when the user doesn't supply a specific MAC address. The default range has an OUI (Organizationally Unique Identifier), of 00:21:F6 and uses the remaining portion of 00:00:00 - FF:FF:FF from which to randomly choose a specific MAC address. This default range is used because the OUI prefix (00:21:f6) is officially registered to Oracle and should not conflict with any other vendors devices. However, that range can be changed.
   
2. Have the ability to manually configure specific MAC addresses When a vnic is created, the user can specify any MAC address. The user supplied MAC address does not have to fall within the default range. The manager will validate that this MAC address is not already used by another vnic created in that manager.
   
3. Allow to program your own OUI The manager allows the specification of an OUI other than the default and a range of addresses to use for the device specific portion of the MAC address.
   
4. Range based allocation of MAC for each Oracle VM Manager instance to avoid collision The users need to explicitly set the range that they want to use. With coordination among Oracle VM Manager instances, you can set the range so that each Oracle VM Manager won't conflict with other Oracle VM Manager instances.
   

Unlock iPhone

I followed the instructions to unlock my iPhone. For business phone, this is the link.

The question is about the last step how to make sure that my iPhone has been unlocked.

Actually it's not that simple. The AT&T representative told me that I should simply perform a backup and restore of my iPhone to complete the unlocking. But how do I know it's unlocked?

I did a simple backup and restore while connecting to iTune. I didn't receive any message regarding unlocking when restore was completed. I read the discussion threads from Apple support forum.

First, connect iPhone with a computer via USB cable and backup your iPhone.

Second, select your iPhone and click on the Restore iPhone to original setting button (not to restore from your existing backup yet).

Then a message will shown up from iTunes that the iPhone is now unlocked.

The rest is to restore iPhone from the most recent backup.

Cable Modem Firmware Update

I had frequent momentary disconnects while using Comcast XFinity Inetnet Service. The cable modem/gateway device I have is a Motorola SURFboard SBG6580.

After searching internet (http://www.idevelopsoftware.com/2011/12/comcast-support-problems-surfboard-sbg6580-intermittent-connection-loss/) and Comcast forum, I attempted to contact Comcast to update the system firmware of the cable modem (SBG6580-3.1.0.0-GA-07-180-NOSH) to a newer version.

To my surprise, the regular Comcast support staff had no clue about firmware, and they didn't know what the firmware is. They also suggested me that I should contact the cable model manufacturer.

Good news is that I had immediate response from that I reached out to their corporate office (Digital Media Outreach).

"We are currently working on a new firmware for the Motorola SGB6580. Once all the testing is completed, we will release the new firmware.  Once the firmware is ready, it will be deployed and update the modem automatically. In some instances, you may need to reboot the modem in order to grab the new firmware."

 Then on April 9th, my cable model firmware was updated automatically.

Information
Standard Specification Compliant	DOCSIS 3.0
Hardware Version	1
Software Version	SBG6580-3.3.1.0-GA-11-070-NOSH

Looks like everything is so for so good, and I haven't experienced any Internet connection drop for more than a week.

Unexpected circuit breaker tripping

We had an unexpected circuit breaker tripping last night. For some reason, I could not reset the breaker from the service panel.

First, I suspected that it may be fault of the GFCI outlet, since it can't be reset. Actually I didn't know that the GFCI can't be reset when there's no power supply or it's not correctly wired. So I went to Home Depot and purchased a new GFCI outlet, and replaced the one at my bathroom. Still I can't reset the tripped circuit breaker. Frustrated, I went to bed, and I thought that I had to look for a licensed electrician tomorrow.

Early in the morning, I called my neighbor, he suggested that I should turn the tripped breaker all the way down, then reset it back. I followed the instructions and it worked.

Here's the lessons learned:

1) for a 15A circuit breaker, should not overload it.

2) when tripped, know the right way to reset it.