Category Archives: TDI

Free TDI Guide on Komodia

Are you aware that in addition to the free LSP and NDIS guides here at Komodia.com, there is also a free TDI guide as well?  Oh it’s true.

This is the place to go when you are searching for information on TDI modify packets and the free TDI firewall source code.  Where else can you find this kind of information regarding TDI for free?

The guide is composed of 4 general areas:

  1. What is TDI?
  2. What is included in TDI?
  3. What are the key features of TDI?
  4. What is the TDI operational information?

Chris

TDI Modify Packets

Microsoft developed TDI (Transport Driver Interface) for the purpose of giving additional functionality combined with flexibility (compared to the existing interfaces). Windows 2000 (and later versions) has the transport providers directly interface with the TDI (Transport Driver Interface).  This allows the TDI (Transport Driver Interface) to offer a more consistent interface with the (NTP) network transport protocols.

Komodia offers a free TDI guide for all your TDI modify packets questions.

Chris

Free TDI Firewall Source Code

Have you been able to view Barak’s free Winsock LSP video?  You can see this video on the same page as the free LSP guide – or you can view the video on YouTube.  The LSP resource page here on Komodia is also a wealth of information.  Are you interested in a free TDI firewall source code?  Then please follow this link.  How about free help winsock functions or any number of other great information?  Komodia is the place to be for all LSP information.

Chris

How to intercept data on Internet

How to intercept data on Internet? This can be done using number of technologies:

  • Winsock LSP – Is good when you want to operate at user level and inspect streams and not packets.
  • TDI – Soon to be phased out, it’s a driver like technology that can be used either in packet or stream level.
  • NDIS – Kernel driver that inspects packets and has total control over the network.
  • WFP – Microsoft new filterting platform, but until Windows XP is phased out, I forsee it will not gain momentum.

Barak

TDI Filter

TDI Filter is sometimes prefered because the thought that there’s no conflicts within this technology, but the opposite is true, it can conflict, the reason that you don’t see many conflicts is because you know in advance not to install two FW products on your machine, and why? because those two can conflict.

Barak

TDI Driver

TDI Driver is mostly used today for personal AV products. I know there are number of parental control, spam filters products that use it as well.

I’m not a fan of TDI, although it has its place in doing networking filtering, it’s time is up and in one and a half year it will be phased out, so I don’t see any reason to start a project using TDI.

You can read this nice article about the difference between LSP and TDI.

Barak

NDIS Filter

NDIS Filter is used to perform packet filtering, modification and inspection, unlike other technologies like LSP and TDI which operate on streams.

NDIS Filter is actually a NDIS IM driver which receives packets (to send or receive), can perform processing on them and then send them to the next layer or drop them, that’s why NDIS IM drivers are used for: Firewalls, corporate firewalls, custom network solutions and more.

When stream operations is requires, NDIS IM is sometimes a bad choice because it imposes additional work to convert packets to streams, which can be avoided if using TDI or LSP.

Barak

Firewall application layer Winsock2

There are several ways to implement a firewall:

  • Winsock LSP – Can be used for an application layer firewall, but it’s mostly not used for various reasons.
  • TDI Driver – Mostly used for personal firewalls, according to Microsoft it will be phased out in the next OS.
  • Ndis IM – Mostly used for gateway firewalls.
  • WFP – The new plaform Microsoft is promoting, in my opinion that until XP is retired this will not gain momentum.

Barak