External connection (internet) slow after connecting device to another network then back to main network

Question

I have a Draytek router set to use Google DNS at work. When I am at work and my Mac is connected to the network, in network settings > DNS I can see that I am connected using Google DNS.

The problem is that if I take my laptop home at night and then bring it back in the morning, it seems to make the connection really slow. But it is fine for all other users who haven't taken their machines off the network overnight. I believe it is a DNS issue, but from what I can see it all seems fine.

I do not have this problem when returning home from work. At home my router is set to use the DNS server of my ISP.

The cure seems to be to restart my computer, but this is quite long to do each morning. Any ideas as to what the issue may be and how to resolve it ?

I tried renewing the DHCP lease, but that does not resolve the problem.

Answer 1

I usually use two wireless networks, my home and university, to browse Internet.

In my university I have been assigned a specific IP address and connect to the Internet through a proxy server where as at home I simply let my router assign me settings via DHCP. On a Mac, it is really easy to make a profile for a specific network rather than input the settings manually every time (Windows eh..) we are in a different network. We can make as many network profiles as we need to and assign the network settings in them. So whenever you go to the particular location, just select the profile from the network preference pane. It’s that simple!

Let’s see how:

1. Select the ‘Network’ pane from System Preferences.

2. In the ‘Locations’ drop down menu, select the option ‘Edit Locations’.

3. Then Click on the little + symbol and type in the location’s name.

4. Now click on the ‘Advanced’ button and the settings for Airport pop up. In the TCP/IP section enter your IP address and Subnet Mask.

5. Enter the Domain Name Server address in the DNS section.

6. If you network uses proxies to browse Internet, change those settings in the ‘Proxies’ tab.

7. Click Ok and then Apply. Next time whenever you want to switch network location, just select it from the locations menu in the Network preference pane.

Setting up the same interface for two networks

The default Automatic location does not accommodate having two configurations for using the same network interface in two different locations. For example, if you used your Ethernet port configured manually at work but via DHCP at home, the Automatic location will not let you avoid switching locations in its default state--you would need to switch locations.