ADSL Channel bonding

Anyone any views or experience with this ?

Jim.

 

Do you mean the system Be have come up with using a second telephone line to
get a 40 meg speed?

 

My view is that if I were to shell out for two line rentals + two ISP
rentals on said lines, I'd forego the benefits of ADSL channel bonding, and
instead use two ISPs for extra resilience.

Bonding at the xDSL layer is better than at the IP layer; for example, it's
better at inbound load balancing.

In an ideal world, everyone would have their own subnet, and if you wanted
to load balance with extra connections, you'd announce your range down all
your lines, tweak the metrics and away you go. Maybe that's an
over-simplified view of it.

 

Some ADSL ISPs already provide a native IPv6 service (with a usual
allocation of a /64 - single subnet - or a /48 - 2^16 subnets). Now that
VM is rolling out DOCSIS 3 hopefully they will follow soon. Sadly, I
cannot see many ISP's offering a peering service to consumers. It would
be a huge amount of work for which the ISP would gain little. I would be
happy to be proved wrong!

 

Coo. To work seamlessly to two ISP's requires you to run BGP and
although ISP's allow it they charge, and you have to be shown to be
competent. And sign a lot of paper. And run a router capable of holding
the world internet routing tables..

Someone who is announcing BGP routes can in theory bring the whole
internet to its knees, and it has been done.

So normally the upstream parties would filter these out, but that adds
overhead to the boundary routers..

No, its far more likely you will run a machine on two IP addresses on
two cards with each card having its own default route to its own ISP..
one via each ISP and use random DNS to see which way the packets come.

Even that is pretty complex if all you want is more bandwidth, which is
why channel bonding works best for most people.

 

I asked earlier is it the 2 telephone line system to be introduced by Be
that we are talking about.
I'm with Be now with their upto 24 meg. and they are excellent.
This is from Think Broadband site.

Be fight back with 45Mbps bonded broadband
Tuesday 16 December 2008 15:46:19 by John Hunt
Be Broadband, the ISP owned by O2's parent company, Telefonica, have
announced today the successful completion of their bonded broadband trial
which ran on the London Paddington exchange. The trial was mainly aimed at
understanding the technical capabilities involved using ADSL2+ over two
telephone lines which were bonded together to make one line. Customers
reported real-world speeds of between 30Mbps and 45Mbps- just 5Mbps shy of
Virgin's headline 50meg speed. Be will be carrying out further trials
through 2009.

A single twisted pair copper phone line is limited in how fast it can
transfer data, and connecting multiple lines together is one solution to try
and increase the bandwidth without deploying equipment closer to the
exchange such as in the BT FTTC trials. One drawback of bonding is that you
will need to pay for two telephone lines, one for each DSL line, which will
increase the cost. DSL does also vary speed depending on the distance from
the exchange (unlike the Virgin cable services) and so the highest speeds
will only be available to those who live the closest.

"We want to push the limits of high-speed broadband. We already offer the
fastest possible broadband on an ADSL line, but we want to take it a step
further. If you want broadband around the 50Mb mark but don't want to go the
cable route, Be wants to offer you a real alternative."

Felix Geyr, (Managing Director) Be Broadband
One point worth making is that although Be services are not limited to the
area of the Virgin cable network, many of the exchanges where Be provide
service will overlap with Virgin, and this will also leave many areas of the
UK unable to get either Virgin's 50meg of the Be bonded broadband.
Competition will breed new services though and if other providers are able
to offer similar services to Virgin's 50meg soon, maybe Virgin will be
forced to up the speed sooner than they thought if they want to keep the
crown of fastest broadband.



Regards,
David

Please reply to News Group

 

I don't know what Jim was specifically asking about but.

AAISP have been offering channel bonding for some time now on ADSL.
They also offer it with ADSL2+ if you are on an exchange that has been
upgraded to 21CN and WBC by BT. They do not limit you to just two
lines, you can have whatever you are willing to pay for:

http://aaisp.net.uk/kb-broadband-bonding.html

They have also been offering ipv6 for some time in spite of BT not
officially supporting it.

 

A few years back now. Client in magazine publishing with lots of
images to be transferred quickly and reliably. Got Andrews & Arnold
to set it all up and worked a treat with pretty close to doubling of
capacity iirc.

 

I would be tempted to have a separate connection for VOIP

Can you bond across different ISPs? You do have some redundancy
against a line fault.

 

There are a few ISPs that will do bonding - I think only on the dataStream
products though - until now, and as Be have their own kit in the exchange,
I guess they can do anything with it...

Same here..

Unless it's additional bandwidth you want...

You can't "bond", but you can load-share. so if you had 2 x 8Mb lines,
one person could still only get 8Mb, but a 2nd person could also get
8Mb at the same time. With true bonding, one person could get 16Mb.

It's not without it's problems though, but with the right kit it can
be made to work very well. You need to make sure that the data stays
going over one line for a "session" (whatever that might be) and try to
avoid asymetric routing (data coming in one line and the replies going
out the other) but there are routers that will do all this for you.
(as well as linux solutions)

Gordon

 

i dont see why a bonded connection is unusable for voip.

Not really.
he weakest link is the ceapest link: you to the exchange. No redunancy
there really. Ok its extra wires, but the usual thing is the digger
through the whole conduit ;-)

ISPS have their own redundancies. i've seen some bloody weird routings
in my time..USA via IIRC Finland was one..

 

There are issues to be taken care of, but they're not insurmountable. You
just need to make sure your phones [or rather, your voice subnet] only ever
get routed down one line; having your SIP traffic and your RTP stream
traversing different lines could cause all sorts of hilarity.

 

But the whole point of bonding is that it IS one line.

Hell you cant even rely on the rest of the internet having fixed
routing..if an ISP has two pipes going to the same place chances are
they will load share over them with equal weight routes.

 

Sorry, I trimmed the bit of the post where we were talking about load
balancing across 2 ISPs from behind NAT. Of course proper bonding is
completely invisible to the upper layers so should work with any
application.

 

OK, but I still don't see that as an issue for VOIP.

Diverse routing and asymmetric routing are all part of the Internet at
large, anyway.

 

You might not, but I can tell you that SIP and certain other VoIP endpoints
get very confused when their traffic isn't consistently routed down one
line or the other.

But the internet at large [ie once your traffic has left your router]
doesn't use NAPT [http://en.wikipedia.org/wiki/Port_address_translation].

 

No good for VOIP though

I have a pair of AAISP bonded lines with a Firebrick 105 at my end.
The main reason for bonding is to get better voip performance, as the
uplink bandwidth is almost doubled. I can get data transfer rates of
about 1.3Mbit/s uplink and 10Mbit/s downlink, although it is hard to
find other sites which can support these speeds. Each line by itself
syncs at 800kbit/s uplink and 6 to 6.5Mbit/s downlink.

Redundancy does help, as sometimes BT kill one line without affecting
the other.

Sending alternate packets down each line does not seem to cause
problems, perhaps because the lines have very similar characteristics.