Windows Core Networking

As Gabe mentioned in his blog post titled “ Xbox 360 Fall Update Includes LLTD ,” the Xbox 360 now includes the Link Layer Topology Discovery (LLTD) protocol. At a basic function level, LLTD gives users a graphical representation of their home network...

Hello all. My name is Charley. I’m the new QoS program manager for Windows Core Networking. It has been a while since we posted our last article about QoS. We want to assure you that we’re still committed to improving this technology and building new...

In a previous post, I discussed traffic coloring. Modifications to a data packet such that the packet itself informs your network equipment that it requires handling different from normal packets such as best effort traffic. In other words, if you looked...

In addition to a completely re-written core networking stack, Windows Vista makes networking a significantly easier proposition for home, small business, and enterprise users. In this multi-part series, I’ll describe some new features which greatly simplify...

Some weeks ago I described 802.1p . It's a way to color traffic on your local network segment. If you have network equipment aware of this tag, you can get strict prioritization at these hops. Still, the tag is at layer-2 and not layer-3; your average...

In Windows Vista, a great deal of effort has gone into making it simple for network applications to take advantage of QoS capable networks. This post focuses on QoS for WiFi networks (both consumer and enterprise) and how the Vista network stack enables...

In his introductory post about the legacy Traffic Control (TC) API , Gabe discussed the host-based model that TC provides. In this post, we will see how Traffic Control APIs can be used to achieve the following for TCP/IPv4 and UDP/IPv4 traffic sent from...

In my first post of this series, I talked about Windows Connect Now (WCN) and how easy it is in Windows Vista to discover, configure, and securely connect devices to a wireless network. In this post, I’ll talk about how to discover PCs, devices, and services...

Disclaimer: Traffic Control (TC) APIs have been marked as deprecated , and will be phased out (eventually removed) when a suitable replacement API is available. No advancements will be made to these APIs (including adding IPv6 support) in their deprecated...

Update: This tool is no longer available on Microsoft Connect and there is no replacement download site. In my last post , I announced the availability of QoS Traffic Generator on Microsoft Connect. In order to help you understand the usage of this...

Consider a case where a network application calls Windows QoS APIs to add a layer-2 IEEE 802.1Q UserPriority tag (almost always referred to as 802.1p ) to outgoing traffic. Ascertaining whether the tag actually got added to an outgoing packet is not as...

Update: This tool is no longer available on Microsoft Connect and there is no replacement download site. I’m posting on behalf of Jim Liu who is a SDET in Windows Core Networking. -- Ari The QoS team is pleased to announce the availability...

If your enterprise wireless AP vendor of choice supports WMM (most likely), and the warriors that wander the halls and conference rooms tote laptops with WMM capable NICs (most likely), you should start taking advantage of this capability. Until Windows...

There has been a lot of buzz about the recent fall update for the Xbox 360; however, an important new feature which has not been mentioned is support for the Link Layer Topology Discovery ( LLTD ) protocol. In its basic form, LLTD allows a Windows Vista...

Congratulations to D-Link (powered by Ubicom ) for being the first ever to acheive a Windows Vista logo for the DIR-655 wireless router. While Buffalo acheived the premium "Certified for Windows Vista" logo , D-Link was first to meet the baseline "Works...

Parts 1 and 2 of this series discussed how to determine whether an 802.1p tag was added to traffic, and how to modify the NDIS light-weight-filter (LWF) sample driver source code to accomplish this task. We do know that you're all very busy and not everyone...

In Gabe’s last post on detecting 802.1p priority tags, he described at a relatively high-level why it is difficult to detect a priority tag using packet tracing applications, as well as the proper way to determine whether a tag was present in a packet...

A while back I wrote about the fundamentals of networking Quality of Service (QoS) including 802.1p and DSCP . Gabe recently wrote about WMM . With Vista soon to hit the market, it's time for us to talk about the new and old QoS APIs. Let's start with...

A few months ago, a technical account manager for a customer sent an email to everyone in Windows networking asking about QoS support in Windows. When answering the question, I realized that there was no single document or web page that outlined the level...

One phrase you'll see time and again within posts is the necessity for "end-to-end" experiments/measurements. Because I repeat this phrase so often, I figured someone would ask why at some point (so I'll beat you to the punch). End-to-end: adj:...

A number of partners who author wireless drivers for Vista have asked how they can ensure their WiFi Wireless Multimedia (WMM) implementation is correct, so I thought I'd be explicit about this very important topic. To begin, read the 4-part series WiFi...

Over the past few months we've been receiving feedback from partners on the new QOS2 API I just wrote about . The first question is often: how do I use this new API in my application? So I thought we should introduce some of the API calls by modifying...

Having spent numerous hours working with analysts reviewing Media Center Extender products to help correct WiFi installation problems, I would like to spare other folks the pain of going through this process uninformed, and share the many ways to successfully...

In my previous posts about WMM support in Vista, I described how Windows network applications can indicate which priority level they desire for traffic sent, and how Native WiFi (NWF) drivers can identify this traffic to provide appropriate prioritization...

My previous post on WiFi QoS (WMM) discussed the four access classes (BG, BE, VI, and VO) available for traffic differentiation. I also highlighted that packets containing either a layer-2 802.1p tag or layer-3 DSCP mark (i.e. packets associated with...