In our guide, “Internet Failover and Redundancy,” we talk about primary and secondary internet access paths, alternate routes, SD-WAN, and how 4G LTE plays as part of those solutions.
It makes sense, then, to talk about homed networks as part of that conversation. As an ITSP (Internet Telephony Service Provider), we get excited about helping clients solve their data and voice needs with the latest and greatest solutions. In doing so, we often assume our clients know what we know when it comes to the fundamentals of LAN/WAN technology. While it’s true in some cases, it’s not in a great many others. Such is often the case regarding homed networks, so we’ll do our best to cover the basics here.
Types of Homed Networks
In the world of internet technology, a homed network simply describes how a business or internet provider is connected to the internet.
There are three types of homed networks, although the terms single-homed and multi-homed are the most commonly used.
A single-homed local area network (LAN) is one which has a single connection to an ISP or provider. The ISP provides a static (never changes) or dynamic (randomly assigned) IP address to the customer’s router. This IP address is what differentiates that client LAN from the rest of the LANs in the world.
The dual-homed network is the one which is least used in today’s environment. In a dual-homed network, a customer is still connected to an ISP via a single connection and a single static or dynamic IP address, but the ISP has two routers on their side. This secondary router provides redundancy at the provider in case the primary router fails.
A multi-homed network is one in which a network is connected to two (or more) ISPs. As stated above, the ISP is the one who provides the client with a static or dynamic IP address. When a client LAN wants to connect to multiple providers, they receive multiple IP addresses. This can create all sorts of problems as the internet only wants to see one IP address per LAN, so the router must use a protocol called BGP (Border Gateway Protocol) to manage these multiple IP addresses.
Why Use a Multi-Homed Network?
Clients choosing to deploy and manage a multi-homed network typically choose to do so for the following reasons:
- Redundancy/Reliability– Because the network has connections to two providers, should one of the connections fail, the router can automatically switch to the alternate path, reducing or eliminating downtime.
- Performance – If one connection is up, but performing poorly, the router can detect errors and choose to route traffic over the secondary path, thereby increasing overall performance.
Running a multi-homed network, however, means paying for connections to multiple providers and having to manage a router running BGP. BGP is complicated to configure and manage and not something the average IT Manager is equipped to handle.
Multi-Homing at the ISP
Here at N2Net, we’re a true, multi-homed network. As an internet and voice provider, it’s our job to be up 24/7 for our clients. In order to do that, we had to build a fault tolerant network with redundancies at every level.
For example, we have multiple (very large/high capacity) upstream connections to the Internet. If the connection from your office to us is a garden hose, our connections upstream to the internet are sewer pipes. These upstream connections are through different, larger carriers like X/O and Level 3. They provide us with IP addresses just like we do for our end user clients, and we use multiple industrial strength routers running BGP.
Because we’re a multi-homed network provider with all of these redundancies in place, we’re able to offer our clients a service level guarantee on direct connections like T1 and Metro Ethernet. This SLA affords clients the confidence of knowing their single-homed connection will be a reliable one.
Knowledge is Power
Hopefully you now have a better understanding about the different types of homed networks and their benefits. This knowledge will hopefully empower you to not only start asking questions about the appropriate network structure, but will also arm you to seek answers from your internet provider about their upstream architecture.
If you’d like more information about the ways you can add redundancy to your LAN, contact an N2Net data and internet expert today!