There are lots of causes of slow internet access, but in this case it was a DNS problem.
The company had changed ISPs at some point in the past and still had old DNS server info on the servers which became a problem after the old ISP took down their name server.
10/27/06 – 5:20pm – rebooted Cisco firewall and switches. Applied patches to FE and BE Exchange servers. Brought network back up and tested. No change. DSLREPORTS.COM test for bandwidth speed clocked at 1854down / 4469up. The low down and quick “up” seemed to indicate a DNS problem. Troubleshot and resolved, removing a Nextweb.net DNS server (18.104.22.168). To see the forwarder list, open DNS from Admin tools, rt-click on server to view and select Properties. Under forwarders there will be server IPs listed with order of preference.
Retested on DSLREPORTS.COM and got 8257down / 4390up. That’s more like it.