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Broadband From more than one ISP

We already offer a number of ways to achieve more reliability by using more than one broadband line. However this relies on us providing the service. There are in fact ways you can have an Internet connection that is not provided by just one supplier!

This is very time limited for legacy IPv4 address space.

Multihoming

Multi-homing means having links via more than one Internet provider for the same IP addresses. This means that traffic will arrive via both providers and can be sent to the Internet via both providers. That way, even if one ISP is completely off-line the service still works and still has the same IP addresses and everything carries on.

It can take a few seconds to react to a failure, but none the less, as long as one of the links is working you are still connected.

You can arrange for one ISP to be preferred for traffic sent to you - which can be important as different ISPs charge in different ways for usage on their broadband links.

Isn't multihoming complicated?

Normally, for muli-homing, you need a BGP router to handle announcing your IP addresses to the Internet. However, this could simply be tied to your broadband line and announced for you by your ISP. That saves the hassle of running a BGP router.

That said, you probably still want a good firewall such as the FireBrick FB2500 or FB2700. This can also handle switching your uplink traffic if one ISP link fails.

Can we really get IP addresses?

Yes! This is called Provider Independant (PI) address space. It is for people that want their own IP addresses rather than being tied to their specific ISP.

  • The IP addresses are yours not part of the ISP. The ISP cannot take them back when the are running out.
  • The IP addresses can be moved to another ISP. This may limit choices of ISP or package as the ISP has to be prepared to announce your IP addresses, but it means you have a choice and still maintain your own IP addresses.
  • The IP addresses can be used with more than one ISP at a time (multi-homing) which is the main reason to get them.
  • The IP addresses could be moved to any location, even in to a data centre for server hosting.

The only thing that is not allowed is sub-letting the IP space, i.e. selling an Internet service yourself using your PI space. It is for your own use.

We are asking customers that currently have a /24 or /25 to consider multi-homing and PI space now - as this will secure their address space for the future even if we start to run out of space. It will also free up their existing space for us to use for other customers.

Why have I not heard of this before?

Until October 2011 you could apply for PI space, but only to cover your needs. If you had 50 computers you could get a block of 64 addresses (a /26) which is no real use as they will not work on the Internet (too small a block).

From October 2011 the policy changed at RIPE (who manage EU IP address space) allowing PI applications to be increased in size to a block of 256 addresses (a /24) if you wanted them for multi-homing. This is big enough to work on the Internet.

Soon, probably later in 2012, RIPE will be down to their last /8 block of Legacy IPv4 space and they will no longer allocate any Legacy IPv4 PI space. You will, however, still be able to apply for IPv6 PI space

This means there is a small window of time, perhaps only a few months, when you can apply for Legacy IPv4 PI space.

What does it cost?

There are some costs. It is possible to apply directly to RIPE for PI space, but it is cheaper and easier to apply via an ISP. It is still your address space, but the ISP handles the contract for you. You can move the contract to RIPE later (and pay more).

The costs (ex VAT) involved are :-

  • One off application charge(s) £100.00. You need at least two of these, one for PI space and one for an AS number. For IPv4 and IPv6 PI space that is two applications, so three in total. If you are an existing customer with a long standing /24 or /25 which you are giving back, we will do this all in one go for one application charge.
  • Ongoing charge for each PI block £5.00 pcm, and for your AS number £5.00 pcm
  • Broadband services from two ISPs. We make no extra charge for announcing your PI space, just our normal prices.

What is an AS number?

In order to multi-home your IP space (a requirement to get the bigger block of legacy IPv4 space) you need an Autonomous System Number (AS). We will announce your PI space using this.

Who would be my second ISP?

We have made aggreements with other ISPs where we will be happy to be the secondary ISP with them, or they will be happy to be the secondary ISP with us. You will need to check their charges for service. Indeed you may want them to be the primary ISP and us as secondary depending on the charges.

We hope to add more to this list over time.