If you are using the older version from 4.x.x and upgrade to newer version 5.x.x or 6.x.x, you can use modify your current setting to use human friendly url. This setting will basically remove the TabId from your site url.
To make some changes, please back up a copy of your web.config file, just in case something goes wrong. Open the web config file and look for friendly URL tag.
<add name="DNNFriendlyUrl" type="DotNetNuke.Services.Url.FriendlyUrl.DNNFriendlyUrlProvider, DotNetNuke.HttpModules" includepagename="true" regexmatch="[^a-zA-Z0-9 _-]"> </add>
Just add the extra attribute urlFormat="humanfriendly" and it should remove the TabId from the url string.
<add name="DNNFriendlyUrl" type="DotNetNuke.Services.Url.FriendlyUrl.DNNFriendlyUrlProvider, DotNetNuke.HttpModules" includepagename="true" regexmatch="[^a-zA-Z0-9 _-]" urlformat="humanfriendly"> </add>