ERPS

EAPS version 4 or 5 ?

This is something I was demoed last year in autum when I visited the Extreme Networks headquarters in the valley.
I was very impressed with the ability to build ladders on ladders, however there is one big scalability issue that I see, you have to have the "control" vlan spann over several ladders if you where to build a ladder on ladder topology.
This makes me believe that while this technology is very good, and has som improvements over EAPS

1. Ability to "test" your rings without disable enable a port
2. No more shared-port limitations.

However something else have to be put in place to extend the ethernet services beyond metro small wan area.

802.1aq Shortest Path Bridging

I was listening to the always interesting packetpushers podcast the other day, one thing caught my attention.
SPB or 802.1aq, this is what PPB should have been from the first time.

A protocol that builds a loop free l2 topology based on mac addresses with ISIS as the topology protocol.
There are two flavours of SBP
SPBV and SPBM
SPBV 
Enables you to transport VID ( VLAN ID ) over the shortest path in the SPB core. This retains the capabilities and functionality with normal switching environments. This version of SPB would fit well in a large datacenter or even across datacenters, or smaller metro areas.
SPBM
Leverages the capabilities of PBB ( Mac-in-Mac), as it should have been =).
What it does is essentially encapsulate the mac in another mac and send it across the SPB core. This way the core devices never have to learn the mac address of the client.
The primary use for this would be carrier ethernet services, E-LAN, E-LINE etc.

I'm really looking forward to see this in action and to see more vendors supporting this.
Apparently both Nortel (avaya), Alcatel-Lucent and Huawei have products supporting this.

More info can be found at
Wikipedia
Packetpusher podcast