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Configure #DirectAccess for Mobile Broadband

Last week I noticed some problems with DirectAccess by using UMTS/3G broadband network of a Dutch mobile provider (KPN). A number of IPv6 translation methods don’t work by default which results DirectAccess by broadband is not always guaranteed. Table below shows a comparison of the various telecom providers and supported IPv6 translation methods.

IPv6 Translation ISP Provider support matrix

Provider 6to4 Teredo IP-HTTPS
KPN (UMTS) X(1) X(2)
Vodafone (UMTS)
  1. Teredo traffic—UDP destination port 3544 inbound and UDP source port 3544 outbound.
  2. 6to4 traffic—Protocol 41 inbound and outbound

In order to get DirectAccess working I contacted KPN on behalf of our customer. By default two Access Point Names (APN) were available; a third was introduced as part of the problem examination. As you can see KPN Default Internet is limited in supporting IPv6 translation methods required for DirectAccess. Even IP-HTTPS is only available after a manual action.

IPv6 Translation v.s. APN support matrix

Access Point Name (APN)




KPN Default Internet




KPN Fast Internet



KPN Advanced Internet




  1. Manual configuration required
  2. Additional dial-up connection required

In order to get Teredo and IP-HTTPS at least working, the helpful KPN operator suggested the following ‘solution’ which introduces the third APN which supports both Teredo and IP-HTTPS.

  • Setup a new dail-up connection
  • Select your modem to use. In my case HP Mobile Broadband Module modem


  • Enter *99# as dail-up phone number

  • Open Phone and Modem dialog box. Select your modem and open properties


  • Select Advanced tab and enter the following additional initialization string: +cgdcont=1,”IP”,”advancedinternet”


Now I am able to use KPN Advanced Internet APN which supports by default Teredo and IP-HTTPS and therefore able to initiate DirectAccess over KPN broadband Internet. Bear in mind your dail-up connection IPv6 properties is selected.

As DirectAccess using IP-HTTPS more or less as safety net plus the number of UMTS users is very limited; I recommend my customer using KPN Fast Internet as it supports IP-HTTPS by default and no additional dail-up connection is required. In the event that only Teredo is possible or supported; KPN Advanced Internet is the right choice for using DirectAccess.

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