Busy, busy, busy
First of all, the 802.1 working group is busier than ever. There are always lots of good ideas coming in, especially from the various wireless groups. Our biggest challenge is that there is simply too little time and too few people to properly address them all. We will need to close out some current working items before starting new ones.
There are four main task groups within 802.1. Here’s a brief look at each one and what’s going on:
Interworking
Interworking was the foundational task group of 802.1. Its focus is on core standards such as Spanning Tree and the various techniques for virtual LANs (VLANs). While the overall intention for Interworking is that it be used across all focus areas, in reality much of the work in this task group is related to “Provider Bridging” — which seeks to use Ethernet in service provider environments, MANs, Internet backbones, telcos, etc.
At a high level, the Interworking standards will broaden the scope of where Ethernet switching can be used, making it more scalable and manageable. Putting Ethernet into provider infrastructures should help reduce the cost and complexity of those environments while bringing more robust, reliable and scalable schemes to general Ethernet switching.
The Interworking general broad standards — the ones used across all 802 products — include:
- LLDP (802.1AB-Rev)
- VLAN MIBs (802.1ap)
- MAC Service (802.1AC)
- Multiple VLAN registration protocol (802.1ak)
- Shortest Path Bridging (802.1aq)
Interworking standards focused specifically on provider networks include:
- Backbone Provider Bridging (802.1ah)
- Two-port MAC relay (802.1aj)
- Data Driven Connectivity Fault Management (802.1Qaw)
- Provider Backbone Traffic Engineering (802.1Qay)
Security
The Security group focuses on enabling the recently completed encryption standard for Ethernet (i.e., MACSec — 802.1AE) with auxiliary protocols and procedures that help make it deployable and usable. This group is also extending the success of the 802.1X protocol with a revision that will support additional deployment scenarios including multiple clients on a port, network infrastructure authentication (e.g., automatic switch-to-switch authentication) and network identity announcements.
Seen from the 50,000-foot level, the goals of the Security working group are to make security mechanisms easier to use and deploy across 802 networks — to make security as plug-and-play as possible.
Another of the key benefits of the Security task group’s work will be to make creating secure network infrastructures a reality — and to make using wired 802.1X more informative and applicable to the internals of the network.
The network identity announcements will give users more information about the wired network they are connected to. It will enable the familiar pop-up window in the corner of your screen you see with wireless networks, except this will work for wired networks as well — similar to the little pop-up screen that says, “You are now connected to the ProCurve network at 1Gbps.” Of course, the real advantage of this network identity is that it can allow the connection to automatically configure and enable encryption if it is available.
Another important work item for the Security task group is Secure Device Identity (802.1AR), which will allow network devices to come with built-in credentials so they can automatically be authenticated and securely added to the network.
Audio/Visual Bridging (AVB)
The Audio/Visual Bridging (AVB) task group is making changes and additions to the bridging standards to allow Ethernet to be used in the home as the interconnect for all a household’s audio/video consumer electronic equipment: TVs, stereos, speakers, TiVo systems, etc. This group is defining a very tight time synchronization protocol so that media streaming throughout the home can be properly played and synchronized.
Imagine having Ethernet-connected speakers all over your house and being able to stream your iPod, movies or TV shows to any or all rooms. You would need the sound to play-out with the proper synchronization to sound right. With just a single receiver and a bunch of displays, connected anywhere in the house, you could watch video wherever you want.
Another important standard to make this vision succeed – and one that’s a main focus of the AVB group – is a stream reservation protocol (802.1Qat). This protocol will ensure that when you are watching TV in your kitchen, there is enough bandwidth for it to succeed without affecting someone else playing networked virtual reality games on the TV in the garage.
Because we are talking about consumer electronics here, the AVB group has to be sure that all this AV coordination is super simple. You can’t expect your neighbor down the street to get the subnet mask right, or be able to configure SNMP correctly, to get his DVD to play. Everything must be plug-and-play and must just work.
The AVB group also is working with other groups to ensure that this very time-sensitive data is being forwarded properly by the bridges. As a result, they are making some very fundamental QoS changes to bridge forwarding. The wireless groups are very interested in this work, too, thanks to the growing use of wireless in the home.
On a final note, while the AVB group’s standards are being defined initially for the home, there are clearly applications of some of this technology in other markets, such as industrial automation and manufacturing. Perhaps these new standards can also truly enable multimedia content delivery in the office, as well. While there are some constraints on how large a network many of these protocols can scale to, you never know — they just might work in the enterprise. At the very least, enterprise employees that take advantage of these protocols at home are going to want them at work, too.
Data Center Bridging (DCB)
The fourth focused task group in 802.1, Data Center Bridging (DCB) is working on technologies to make Ethernet the single converged fabric in the data center.
Currently, we have Fibre Channel, InfiniBand and Ethernet in the data center, each playing a unique role – and each with different application requirements. For instance, Fibre Channel and InfiniBand do not tolerate packet loss. Applications such as Fibre Channel over Ethernet and high-performance message-passing protocols do not use TCP and are not very tolerant of losses.
With DCB, the goal is to focus on Ethernet as a unifying data center fabric. To meet the requirements of the applications that currently run in Fibre Channel and InfiniBand, it is necessary to enhance the way Ethernet manages congestion and packet loss, and to enhance the forwarding and scheduling of the Ethernet switches when mixing traffic from all three fabrics together.
Two specific DCB efforts are 802.1Qau and 802.1Qbb, which are focused on signaling congestion conditions to other Ethernet switches and end points so they can slow down or stop sending traffic to avoid dropping packets.
Another important work item in the DCB group is to enhance transmission selection algorithms in switches. Most vendors (including ProCurve) implement enhanced scheduling schemes, but the current 802.1Q standards specify only strict priority scheduling. The new DCB enhancements will make it easier to create a converged Ethernet fabric that supports the application requirements of the various technologies in the data center.
Decoding the standards’ names
It’s kind of ironic that in the standards arena, all the number-and-letter combinations look pretty random and as if they don’t follow any obvious rhyme or reason. In other words, they don’t look very “standard” at all.
But here are some formulas that might help clarify why 802.1 standards have the names they do, why some standards use capital letters and others don’t, etc. Think of it as a secret decoder ring for the 802.1 world.
First of all, the letters themselves don’t have any specific meaning and are just incremented alphabetically as we start a new standard. After 802.1z we rolled to 802.1aa, then 802.1ab and so on. It was just pure coincidence that 802.1p was the standard for “priority.”
Now for the more confusing part: the capitalization. Historically, a capital letter denoted a “stand-alone” document and a lower-case letter denoted an update to an existing stand-alone document. For example, 802.1AB is a stand-alone standard — you should be able to simply pick up that document and start implementing. A standard such as 802.1s — multiple Spanning Trees — was a supplement to the VLAN standard 802.1Q to add multiple spanning trees.
Recently we have adopted a new notation with even more information in the name. The lower-case letters still denote an update to another stand-alone standard, but we now list that stand-alone standard in the name, as well. For example, 802.1Qaw is an update to 802.1Q to add management of data-driven and data-dependent connectivity faults.
Finally, if a stand-alone standard is being completely revised, then we put the notation REV in the name. For example, 802.1X-REV is the next generation of 802.1X that will be produced. When the standard is finally completed, we add the year to the end. So IEEE 802.1AE-2006 is the completed standard for MACSec.
Hope that clarifies the naming conventions for the dot1 world. As I said, this is an extremely busy and productive working group. I look forward to my next two years serving as vice chair, and to providing future updates on the group’s progress.
Paul Congdon is Chief Technology Officer of HP ProCurve , as well as an HP Fellow. |
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