Re: Metro Ethernet, VPLS clarifications

[david peahi <davidpeahi () gmail com>]

The Metro Ethernet Forum (MEF) develops standards for Metro Ethernet, which
are generally implemented by telcos/cablecos. See the following link:

http://metroethernetforum.org/

The 2 biggest problems I have found with telco/cableco MEF services are:

1. In network configurations where all sites are relatively close together
(< 500 miles), the telco/cableco SLAs are meaningless, bordering on being
fraudulent. For instance SLAs of 50 ms round trip for bronze service, and
20 ms for gold service are enough network transit time to send packets 5000
miles and 2000 miles respectively. This is like buying homeowners'
insurance on a $500K house with a $10 million deductible (50 ms SLA), and a
more expensive policy has a $5 million deductible (20 ms SLA).
2. The MEF spec does not address directed multicast, as opposed to a native
Ethernet switched network which updates the mac tables with each next hop
for the multicast requestor (video for instance) tracking the Layer 3
multicast routing protocol shortest path. So in MEF implementations where
users view a constant 10 Mbps (for example) multicast video stream between
a requestor and a multicast source, this 10 Mbps gets broadcast out all
switch ports in a users' MEF VLAN, rendering low speed MEF connections at
all other users' locations useless.

David

On Tue, Feb 5, 2013 at 7:54 PM, Abzal Sembay <serian.reg () gmail com> wrote:

> 05.02.2013 19:58, Scott Helms ?????:
>
> > Metro-Ethernet is generally the term used to describe Ethernet used as a
> > WAN connection or as a point to point connection.  There was at one time
> > the concept of a MAN (Metro Area Network) but "metro" ethernet is now
> > available in more scenarios than that described.  The connectivity can be
> > over fiber or copper and the speed delivered can be as low as a few mbps
> > but commercially available offerings normally start at 5-10 mbps.  On the
> > high end its possible to get gigabit and faster connections in certain
> > areas.
> > http://en.wikipedia.org/wiki/**Metro_E<http://en.wikipedia.org/wiki/Metro_E>
> >
> >
> > VPLS stands for Virtual Private Lan Services.  This an umbrella
> > technology that allows for the bridging of layer 2 traffic across various
> > layer 2 & 3 networks.  This is generally used as a replacement for a point
> > to point metro ethernet (or other) connection.
> >
> > http://en.wikipedia.org/wiki/**VPLS <http://en.wikipedia.org/wiki/VPLS>
> >
> >
> > On Mon, Feb 4, 2013 at 11:06 PM, Abzal Sembay <serian.reg () gmail com<mailto:
> > serian.reg () gmail com>> wrote:
> >
> >     Hi experts,
> >
> >     I need some clarifications on these terms. Could somebody give
> >     explanations or share some links?
> >     When and how are these technologies used?
> >
> >     Thanks in advance.
> >
> >     --     Regards,
> >
> >     Abzal
> >
> >
> >
> >
> >
> > --
> > Scott Helms
> > Vice President of Technology
> > ZCorum
> > (678) 507-5000
> > ------------------------------**--
> > http://twitter.com/kscotthelms
> > ------------------------------**--
> Thank you, Scott and all of you for your answers and time.
>
> From my understanding M-Ethernet is a some kind of service. Standartized
> technology that allows to connect multiple different networks.  And it is
> independent from physical and datalink layers. And nowadays which tecnology
> is the most used(VPLS or Metro)? What about MPLS? Sorry I'm a little
> confused. I really want to understand.
>
>
> --
> Regards,
>
> Abzal